extcon-next regression ?

DISCUSSION Felipe Balbi 2 participants 9 messages Apr 23, 2014 – Apr 24, 2014

Subsystems (2)

Multifunction devices (MFD) External connector subsystem (extcon)

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Felipe Balbi

author

2014-04-23 16:40 UTC #0 lore raw

Hi Chanwoo,

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Any ideas ??

Signature · 1 line

balbi

Felipe Balbi

author

2014-04-23 17:20 UTC #1 lore raw

Hi,

Quoted 182 lines · Felipe Balbi

Hi Chanwoo,

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

This patch add APIs to control the extcon device on extcon provider driver. The extcon_dev_allocate() allocates the memory of extcon device and initializes supported cables. And then extcon_dev_free() decrement the reference of the device of extcon device and free the memory of the extcon device. This APIs must need to implement devm_extcon_dev_allocate()/free() APIs.

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

git bisect start
# good: [a798c10faf62a505d24e5f6213fbaf904a39623f] Linux 3.15-rc2
git bisect good a798c10faf62a505d24e5f6213fbaf904a39623f
# bad: [3019b77470c1f10b23438917f73cad386e4f7f02] Merge branch 'extcon-next' of git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/extcon into merge git bisect bad 3019b77470c1f10b23438917f73cad386e4f7f02
# bad: [f68f3aeb530b1efe3d6bf583db7a6255d15544eb] extcon: max14577: Use devm_extcon_dev_allocate for extcon_dev
git bisect bad f68f3aeb530b1efe3d6bf583db7a6255d15544eb
# good: [489096faca790b75653478d2f9d4774dd4f07b93] extcon: gpio: Use devm_extcon_dev_register()
git bisect good 489096faca790b75653478d2f9d4774dd4f07b93
# good: [5a451cded8793798e0d409e6ed6f8c53785ae929] extcon: arizona: Use devm_extcon_dev_register()
git bisect good 5a451cded8793798e0d409e6ed6f8c53785ae929
# bad: [cbe68e2d93df61fe40ddfea4d75f169fabadc155] extcon: Add devm_extcon_dev_allocate/free to manage the resource of extcon device git bisect bad cbe68e2d93df61fe40ddfea4d75f169fabadc155
# bad: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device git bisect bad 854b85057cc6b90a326b731174b6c6dbbf34222a

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

And the bug is very simple and affects *all* users of extcon class, which tells me that this big series switching over to devm_* resources wasn't tested at all. Originally extcon_dev_register() was calling device_register(&edev->dev) which will call device_initialize(dev) followed by device_add(dev).

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!

Please fix that up ASAP.

cheers

Signature · 1 line

balbi

Felipe Balbi

author

2014-04-23 18:28 UTC #2 lore raw

Hi,

Quoted 637 lines · Felipe Balbi

Quoted 180 lines

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Quoted 5 lines

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!
Please fix that up ASAP.

After fixing (actually, hacking) the first problem:

drivers/extcon/extcon-class.c +1 -1

index 677c502..d1b74e8 100644
@@ -594,7 +594,7 @@ int extcon_dev_register(struct extcon_dev *edev)
 	}
 	dev_set_name(&edev->dev, "%s", edev->name);
 
-	ret = device_add(&edev->dev);
+	ret = device_register(&edev->dev);
 	if (ret) {
 		put_device(&edev->dev);
 		return ret;

another problem shows up when connecting the USB cable:

[   99.386598] INFO: trying to register non-static key.
[   99.391787] the code is fine but needs lockdep annotation.
[   99.397529] turning off the locking correctness validator.
[   99.403262] CPU: 1 PID: 757 Comm: irq/39-palmas Tainted: G        W     3.15.0-rc2-00041-g3019b77-dirty #315
[   99.413552] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[   99.421658] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[   99.429216] [<c05426b4>] (dump_stack) from [<c0085584>] (__lock_acquire+0x17c8/0x1bc0)
[   99.437498] [<c0085584>] (__lock_acquire) from [<c008617c>] (lock_acquire+0xa4/0x100)
[   99.445692] [<c008617c>] (lock_acquire) from [<c05486e0>] (_raw_spin_lock_irqsave+0x38/0x4c)
[   99.454530] [<c05486e0>] (_raw_spin_lock_irqsave) from [<c0462610>] (extcon_update_state+0x20/0x20c)
[   99.464084] [<c0462610>] (extcon_update_state) from [<c0462f6c>] (palmas_vbus_irq_handler+0x60/0xa4)
[   99.473640] [<c0462f6c>] (palmas_vbus_irq_handler) from [<c0091ce0>] (handle_nested_irq+0xa0/0x100)
[   99.483109] [<c0091ce0>] (handle_nested_irq) from [<c0368e20>] (regmap_irq_thread+0x17c/0x300)
[   99.492120] [<c0368e20>] (regmap_irq_thread) from [<c008ff20>] (irq_thread_fn+0x1c/0x40)
[   99.500586] [<c008ff20>] (irq_thread_fn) from [<c0090238>] (irq_thread+0x12c/0x188)
[   99.508600] [<c0090238>] (irq_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[   99.515882] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[   99.523534] palmas-usb palmas_usb.7: USB cable is attached

Again, another sign that this was not tested! That is caused by the same commit. It seems like you want *all* extcon users to call devm_extcon_dev_allocate() but you didn't fix palmas to do that, I suspect a few other drivers are missing that patch too.

Here's the change for palmas:

From: Felipe Balbi <[email protected]>
Subject: extcon: palmas: fix regression on extcon-next

All extcon users must rely on devm_extcon_dev_allocate() otherwise device registration will fail.

Signed-of-by Felipe Balbi <[email protected]>

---

drivers/extcon/extcon-palmas.c +19 ~~-15~~

index 1a770e0..23a20d9 100644
@@ -57,7 +57,7 @@ static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
 	if (vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS) {
 		if (palmas_usb->linkstat != PALMAS_USB_STATE_VBUS) {
 			palmas_usb->linkstat = PALMAS_USB_STATE_VBUS;
-			extcon_set_cable_state(&palmas_usb->edev, "USB", true);
+			extcon_set_cable_state(palmas_usb->edev, "USB", true);
 			dev_info(palmas_usb->dev, "USB cable is attached\n");
 		} else {
 			dev_dbg(palmas_usb->dev,

@@ -66,7 +66,7 @@ static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
 	} else if (!(vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS)) {
 		if (palmas_usb->linkstat == PALMAS_USB_STATE_VBUS) {
 			palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
-			extcon_set_cable_state(&palmas_usb->edev, "USB", false);
+			extcon_set_cable_state(palmas_usb->edev, "USB", false);
 			dev_info(palmas_usb->dev, "USB cable is detached\n");
 		} else {
 			dev_dbg(palmas_usb->dev,

@@ -93,7 +93,7 @@ static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
 			PALMAS_USB_ID_INT_LATCH_CLR,
 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_GND);
 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", true);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", true);
 		dev_info(palmas_usb->dev, "USB-HOST cable is attached\n");
 	} else if ((set & PALMAS_USB_ID_INT_SRC_ID_FLOAT) &&
 				(id_src & PALMAS_USB_ID_INT_SRC_ID_FLOAT)) {

@@ -101,17 +101,17 @@ static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
 			PALMAS_USB_ID_INT_LATCH_CLR,
 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", false);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", false);
 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_ID) &&
 				(!(set & PALMAS_USB_ID_INT_SRC_ID_GND))) {
 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", false);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", false);
 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_DISCONNECT) &&
 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", true);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", true);
 		dev_info(palmas_usb->dev, " USB-HOST cable is attached\n");
 	}

@@ -187,15 +187,19 @@ static int palmas_usb_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, palmas_usb);
 
-	palmas_usb->edev.supported_cable = palmas_extcon_cable;
-	palmas_usb->edev.dev.parent = palmas_usb->dev;
-	palmas_usb->edev.name = kstrdup(node->name, GFP_KERNEL);
-	palmas_usb->edev.mutually_exclusive = mutually_exclusive;
+	palmas_usb->edev = devm_extcon_dev_allocate(&pdev->dev, palmas_extcon_cable);
+	if (!palmas_usb->edev) {
+		dev_err(&pdev->dev, "failed to allocate extcon_device\n");
+		return -ENOMEM;
+	}
+	palmas_usb->edev->dev.parent = palmas_usb->dev;
+	palmas_usb->edev->name = kstrdup(node->name, GFP_KERNEL);
+	palmas_usb->edev->mutually_exclusive = mutually_exclusive;
 
-	status = devm_extcon_dev_register(&pdev->dev, &palmas_usb->edev);
+	status = devm_extcon_dev_register(&pdev->dev, palmas_usb->edev);
 	if (status) {
 		dev_err(&pdev->dev, "failed to register extcon device\n");
-		kfree(palmas_usb->edev.name);
+		kfree(palmas_usb->edev->name);
 		return status;
 	}

@@ -209,7 +213,7 @@ static int palmas_usb_probe(struct platform_device *pdev)
 		if (status < 0) {
 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
 					palmas_usb->id_irq, status);
-			kfree(palmas_usb->edev.name);
+			kfree(palmas_usb->edev->name);
 			return status;
 		}
 	}

@@ -224,7 +228,7 @@ static int palmas_usb_probe(struct platform_device *pdev)
 		if (status < 0) {
 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
 					palmas_usb->vbus_irq, status);
-			kfree(palmas_usb->edev.name);
+			kfree(palmas_usb->edev->name);
 			return status;
 		}
 	}

@@ -238,7 +242,7 @@ static int palmas_usb_remove(struct platform_device *pdev)
 {
 	struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
 
-	kfree(palmas_usb->edev.name);
+	kfree(palmas_usb->edev->name);
 
 	return 0;
 }

include/linux/mfd/palmas.h +1 -1

index 9974e38..b8f87b7 100644
@@ -415,7 +415,7 @@ struct palmas_usb {
 	struct palmas *palmas;
 	struct device *dev;
 
-	struct extcon_dev edev;
+	struct extcon_dev *edev;
 
 	int id_otg_irq;
 	int id_irq;

I tested this on OMAP5 but there's still *another* regression, it takes some 15 seconds for enumeration to happen after cable is attached:

[  126.476804] palmas-usb palmas_usb.7: USB cable is attached
[  141.912688] g_mass_storage gadget: super-speed config #1: Linux File-Backed Storage

Dure, seriously ??? I'll continue debugging this, but god damn!!!!

cheers

Signature · 1 line

balbi

Chanwoo Choi

maintainer

2014-04-24 05:35 UTC #3 lore raw

Hi Felipe,

Thanks for your test and review.

Quoted 653 lines · Felipe Balbi

Hi,

Quoted 637 lines · Felipe Balbi

Quoted 180 lines

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Quoted 5 lines

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!
Please fix that up ASAP.

After fixing (actually, hacking) the first problem:

drivers/extcon/extcon-class.c +0 -0

index 677c502..d1b74e8 100644

drivers/extcon/extcon-class.c int extcon_dev_register(struct extcon_dev *edev) · line 597

Quoted 5 lines

drivers/extcon/extcon-class.c +1 -1

@@ -594,7 +594,7 @@ int extcon_dev_register(struct extcon_dev *edev)
 	}
 	dev_set_name(&edev->dev, "%s", edev->name);
 
-	ret = device_add(&edev->dev);
+	ret = device_register(&edev->dev);

It is not bug.

As I comment on previous reply,
This patchset add 'extcon_dev_allocate()' to allocate the memory of extcon device. So, extcon_dev_allocate() calls 'device_initialize(" before calling extcon_dev_register() and then extcon_dev_register() calls device_add() function as following.

edev = extcon_dev_allocate()

	{
		...
		device_initialize(&edev->dev) (line.683)
	}

ret = extcon_dev_register(edev)

	{
		...
		device_add(&edev->dev);
		...
	}

Quoted 32 lines

drivers/extcon/extcon-class.c +0 -0

 	if (ret) {
 		put_device(&edev->dev);
 		return ret;

another problem shows up when connecting the USB cable:

[   99.386598] INFO: trying to register non-static key.
[   99.391787] the code is fine but needs lockdep annotation.
[   99.397529] turning off the locking correctness validator.
[   99.403262] CPU: 1 PID: 757 Comm: irq/39-palmas Tainted: G        W     3.15.0-rc2-00041-g3019b77-dirty #315
[   99.413552] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[   99.421658] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[   99.429216] [<c05426b4>] (dump_stack) from [<c0085584>] (__lock_acquire+0x17c8/0x1bc0)
[   99.437498] [<c0085584>] (__lock_acquire) from [<c008617c>] (lock_acquire+0xa4/0x100)
[   99.445692] [<c008617c>] (lock_acquire) from [<c05486e0>] (_raw_spin_lock_irqsave+0x38/0x4c)
[   99.454530] [<c05486e0>] (_raw_spin_lock_irqsave) from [<c0462610>] (extcon_update_state+0x20/0x20c)
[   99.464084] [<c0462610>] (extcon_update_state) from [<c0462f6c>] (palmas_vbus_irq_handler+0x60/0xa4)
[   99.473640] [<c0462f6c>] (palmas_vbus_irq_handler) from [<c0091ce0>] (handle_nested_irq+0xa0/0x100)
[   99.483109] [<c0091ce0>] (handle_nested_irq) from [<c0368e20>] (regmap_irq_thread+0x17c/0x300)
[   99.492120] [<c0368e20>] (regmap_irq_thread) from [<c008ff20>] (irq_thread_fn+0x1c/0x40)
[   99.500586] [<c008ff20>] (irq_thread_fn) from [<c0090238>] (irq_thread+0x12c/0x188)
[   99.508600] [<c0090238>] (irq_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[   99.515882] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[   99.523534] palmas-usb palmas_usb.7: USB cable is attached

Here's the change for palmas:

Quoted 7 lines

From: Felipe Balbi <[email protected]>
Subject: extcon: palmas: fix regression on extcon-next
All extcon users must rely on devm_extcon_dev_allocate() otherwise device registration will fail.
Signed-of-by Felipe Balbi <[email protected]>

I sent already following patch to use devm_extcon_dev_* function
But, following patch didn't get ack or review message from mfd maintainer and author. So, I have not yet to merge this patch on extcon-next branch
[1]
[PATCHv2 6/9] extcon: palmas: Use devm_extcon_dev_allocate for extcon_dev
- https://lkml.org/lkml/2014/4/21/162

If you possible, I'd like you to test this patch[1] based on extcon-next branch.

Thanks,
Chanwoo Choi

Quoted 131 lines

---

drivers/extcon/extcon-palmas.c +19 ~~-15~~

index 1a770e0..23a20d9 100644
@@ -57,7 +57,7 @@ static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
 	if (vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS) {
 		if (palmas_usb->linkstat != PALMAS_USB_STATE_VBUS) {
 			palmas_usb->linkstat = PALMAS_USB_STATE_VBUS;
-			extcon_set_cable_state(&palmas_usb->edev, "USB", true);
+			extcon_set_cable_state(palmas_usb->edev, "USB", true);
 			dev_info(palmas_usb->dev, "USB cable is attached\n");
 		} else {
 			dev_dbg(palmas_usb->dev,

@@ -66,7 +66,7 @@ static irqreturn_t palmas_vbus_irq_handler(int irq, void *_palmas_usb)
 	} else if (!(vbus_line_state & PALMAS_INT3_LINE_STATE_VBUS)) {
 		if (palmas_usb->linkstat == PALMAS_USB_STATE_VBUS) {
 			palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
-			extcon_set_cable_state(&palmas_usb->edev, "USB", false);
+			extcon_set_cable_state(palmas_usb->edev, "USB", false);
 			dev_info(palmas_usb->dev, "USB cable is detached\n");
 		} else {
 			dev_dbg(palmas_usb->dev,

@@ -93,7 +93,7 @@ static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
 			PALMAS_USB_ID_INT_LATCH_CLR,
 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_GND);
 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", true);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", true);
 		dev_info(palmas_usb->dev, "USB-HOST cable is attached\n");
 	} else if ((set & PALMAS_USB_ID_INT_SRC_ID_FLOAT) &&
 				(id_src & PALMAS_USB_ID_INT_SRC_ID_FLOAT)) {

@@ -101,17 +101,17 @@ static irqreturn_t palmas_id_irq_handler(int irq, void *_palmas_usb)
 			PALMAS_USB_ID_INT_LATCH_CLR,
 			PALMAS_USB_ID_INT_EN_HI_CLR_ID_FLOAT);
 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", false);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", false);
 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_ID) &&
 				(!(set & PALMAS_USB_ID_INT_SRC_ID_GND))) {
 		palmas_usb->linkstat = PALMAS_USB_STATE_DISCONNECT;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", false);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", false);
 		dev_info(palmas_usb->dev, "USB-HOST cable is detached\n");
 	} else if ((palmas_usb->linkstat == PALMAS_USB_STATE_DISCONNECT) &&
 				(id_src & PALMAS_USB_ID_INT_SRC_ID_GND)) {
 		palmas_usb->linkstat = PALMAS_USB_STATE_ID;
-		extcon_set_cable_state(&palmas_usb->edev, "USB-HOST", true);
+		extcon_set_cable_state(palmas_usb->edev, "USB-HOST", true);
 		dev_info(palmas_usb->dev, " USB-HOST cable is attached\n");
 	}

@@ -187,15 +187,19 @@ static int palmas_usb_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, palmas_usb);
 
-	palmas_usb->edev.supported_cable = palmas_extcon_cable;
-	palmas_usb->edev.dev.parent = palmas_usb->dev;
-	palmas_usb->edev.name = kstrdup(node->name, GFP_KERNEL);
-	palmas_usb->edev.mutually_exclusive = mutually_exclusive;
+	palmas_usb->edev = devm_extcon_dev_allocate(&pdev->dev, palmas_extcon_cable);
+	if (!palmas_usb->edev) {
+		dev_err(&pdev->dev, "failed to allocate extcon_device\n");
+		return -ENOMEM;
+	}
+	palmas_usb->edev->dev.parent = palmas_usb->dev;
+	palmas_usb->edev->name = kstrdup(node->name, GFP_KERNEL);
+	palmas_usb->edev->mutually_exclusive = mutually_exclusive;
 
-	status = devm_extcon_dev_register(&pdev->dev, &palmas_usb->edev);
+	status = devm_extcon_dev_register(&pdev->dev, palmas_usb->edev);
 	if (status) {
 		dev_err(&pdev->dev, "failed to register extcon device\n");
-		kfree(palmas_usb->edev.name);
+		kfree(palmas_usb->edev->name);
 		return status;
 	}

@@ -209,7 +213,7 @@ static int palmas_usb_probe(struct platform_device *pdev)
 		if (status < 0) {
 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
 					palmas_usb->id_irq, status);
-			kfree(palmas_usb->edev.name);
+			kfree(palmas_usb->edev->name);
 			return status;
 		}
 	}

@@ -224,7 +228,7 @@ static int palmas_usb_probe(struct platform_device *pdev)
 		if (status < 0) {
 			dev_err(&pdev->dev, "can't get IRQ %d, err %d\n",
 					palmas_usb->vbus_irq, status);
-			kfree(palmas_usb->edev.name);
+			kfree(palmas_usb->edev->name);
 			return status;
 		}
 	}

@@ -238,7 +242,7 @@ static int palmas_usb_remove(struct platform_device *pdev)
 {
 	struct palmas_usb *palmas_usb = platform_get_drvdata(pdev);
 
-	kfree(palmas_usb->edev.name);
+	kfree(palmas_usb->edev->name);
 
 	return 0;
 }

include/linux/mfd/palmas.h +1 -1

index 9974e38..b8f87b7 100644
@@ -415,7 +415,7 @@ struct palmas_usb {
 	struct palmas *palmas;
 	struct device *dev;
 
-	struct extcon_dev edev;
+	struct extcon_dev *edev;
 
 	int id_otg_irq;
 	int id_irq;

I tested this on OMAP5 but there's still *another* regression, it takes some 15 seconds for enumeration to happen after cable is attached:

[  126.476804] palmas-usb palmas_usb.7: USB cable is attached
[  141.912688] g_mass_storage gadget: super-speed config #1: Linux File-Backed Storage

Dure, seriously ??? I'll continue debugging this, but god damn!!!!

cheers

Felipe Balbi

author

2014-04-24 06:47 UTC #4 lore raw

Hi,

Quoted 725 lines · Chanwoo Choi

Hi Felipe,

Thanks for your test and review.

Quoted 653 lines · Felipe Balbi

Hi,

Quoted 637 lines · Felipe Balbi

Quoted 180 lines

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Quoted 5 lines

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!
Please fix that up ASAP.

After fixing (actually, hacking) the first problem:

drivers/extcon/extcon-class.c +0 -0

index 677c502..d1b74e8 100644

drivers/extcon/extcon-class.c int extcon_dev_register(struct extcon_dev *edev) · line 597

Quoted 5 lines

drivers/extcon/extcon-class.c +1 -1

@@ -594,7 +594,7 @@ int extcon_dev_register(struct extcon_dev *edev)
 	}
 	dev_set_name(&edev->dev, "%s", edev->name);
 
-	ret = device_add(&edev->dev);
+	ret = device_register(&edev->dev);

It is not bug.

edev = extcon_dev_allocate()

	{
		...
		device_initialize(&edev->dev) (line.683)
	}

ret = extcon_dev_register(edev)

	{
		...
		device_add(&edev->dev);
		...
	}

Quoted 32 lines

drivers/extcon/extcon-class.c +0 -0

 	if (ret) {
 		put_device(&edev->dev);
 		return ret;

another problem shows up when connecting the USB cable:

[   99.386598] INFO: trying to register non-static key.
[   99.391787] the code is fine but needs lockdep annotation.
[   99.397529] turning off the locking correctness validator.
[   99.403262] CPU: 1 PID: 757 Comm: irq/39-palmas Tainted: G        W     3.15.0-rc2-00041-g3019b77-dirty #315
[   99.413552] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[   99.421658] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[   99.429216] [<c05426b4>] (dump_stack) from [<c0085584>] (__lock_acquire+0x17c8/0x1bc0)
[   99.437498] [<c0085584>] (__lock_acquire) from [<c008617c>] (lock_acquire+0xa4/0x100)
[   99.445692] [<c008617c>] (lock_acquire) from [<c05486e0>] (_raw_spin_lock_irqsave+0x38/0x4c)
[   99.454530] [<c05486e0>] (_raw_spin_lock_irqsave) from [<c0462610>] (extcon_update_state+0x20/0x20c)
[   99.464084] [<c0462610>] (extcon_update_state) from [<c0462f6c>] (palmas_vbus_irq_handler+0x60/0xa4)
[   99.473640] [<c0462f6c>] (palmas_vbus_irq_handler) from [<c0091ce0>] (handle_nested_irq+0xa0/0x100)
[   99.483109] [<c0091ce0>] (handle_nested_irq) from [<c0368e20>] (regmap_irq_thread+0x17c/0x300)
[   99.492120] [<c0368e20>] (regmap_irq_thread) from [<c008ff20>] (irq_thread_fn+0x1c/0x40)
[   99.500586] [<c008ff20>] (irq_thread_fn) from [<c0090238>] (irq_thread+0x12c/0x188)
[   99.508600] [<c0090238>] (irq_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[   99.515882] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[   99.523534] palmas-usb palmas_usb.7: USB cable is attached

Here's the change for palmas:

Quoted 7 lines

From: Felipe Balbi <[email protected]>
Subject: extcon: palmas: fix regression on extcon-next
All extcon users must rely on devm_extcon_dev_allocate() otherwise device registration will fail.
Signed-of-by Felipe Balbi <[email protected]>

Quoted 8 lines

I sent already following patch to use devm_extcon_dev_* function
But, following patch didn't get ack or review message from mfd maintainer and author. So, I have not yet to merge this patch on extcon-next branch
[1]
[PATCHv2 6/9] extcon: palmas: Use devm_extcon_dev_allocate for extcon_dev
- https://lkml.org/lkml/2014/4/21/162
If you possible, I'd like you to test this patch[1] based on extcon-next branch.

I'll do that. I can't seem to find that patch in my inbox even though I'm in Cc.

One thing though, the current order of your next branch will create a non-bisectable history, you need to shuffle things around to avoid this not working spots.

Signature · 1 line

balbi

Chanwoo Choi

maintainer

2014-04-24 08:13 UTC #5 lore raw

Hi,

Quoted 735 lines · Felipe Balbi

Hi,

Quoted 732 lines · Chanwoo Choi

Hi Felipe,

Thanks for your test and review.

Quoted 653 lines · Felipe Balbi

Hi,

Quoted 637 lines · Felipe Balbi

Quoted 180 lines

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Quoted 5 lines

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!
Please fix that up ASAP.

After fixing (actually, hacking) the first problem:

drivers/extcon/extcon-class.c +0 -0

index 677c502..d1b74e8 100644

drivers/extcon/extcon-class.c int extcon_dev_register(struct extcon_dev *edev) · line 597

Quoted 5 lines

drivers/extcon/extcon-class.c +1 -1

@@ -594,7 +594,7 @@ int extcon_dev_register(struct extcon_dev *edev)
 	}
 	dev_set_name(&edev->dev, "%s", edev->name);
 
-	ret = device_add(&edev->dev);
+	ret = device_register(&edev->dev);

It is not bug.

edev = extcon_dev_allocate()

	{
		...
		device_initialize(&edev->dev) (line.683)
	}

ret = extcon_dev_register(edev)

	{
		...
		device_add(&edev->dev);
		...
	}

Quoted 32 lines

drivers/extcon/extcon-class.c +0 -0

 	if (ret) {
 		put_device(&edev->dev);
 		return ret;

another problem shows up when connecting the USB cable:

[   99.386598] INFO: trying to register non-static key.
[   99.391787] the code is fine but needs lockdep annotation.
[   99.397529] turning off the locking correctness validator.
[   99.403262] CPU: 1 PID: 757 Comm: irq/39-palmas Tainted: G        W     3.15.0-rc2-00041-g3019b77-dirty #315
[   99.413552] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[   99.421658] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[   99.429216] [<c05426b4>] (dump_stack) from [<c0085584>] (__lock_acquire+0x17c8/0x1bc0)
[   99.437498] [<c0085584>] (__lock_acquire) from [<c008617c>] (lock_acquire+0xa4/0x100)
[   99.445692] [<c008617c>] (lock_acquire) from [<c05486e0>] (_raw_spin_lock_irqsave+0x38/0x4c)
[   99.454530] [<c05486e0>] (_raw_spin_lock_irqsave) from [<c0462610>] (extcon_update_state+0x20/0x20c)
[   99.464084] [<c0462610>] (extcon_update_state) from [<c0462f6c>] (palmas_vbus_irq_handler+0x60/0xa4)
[   99.473640] [<c0462f6c>] (palmas_vbus_irq_handler) from [<c0091ce0>] (handle_nested_irq+0xa0/0x100)
[   99.483109] [<c0091ce0>] (handle_nested_irq) from [<c0368e20>] (regmap_irq_thread+0x17c/0x300)
[   99.492120] [<c0368e20>] (regmap_irq_thread) from [<c008ff20>] (irq_thread_fn+0x1c/0x40)
[   99.500586] [<c008ff20>] (irq_thread_fn) from [<c0090238>] (irq_thread+0x12c/0x188)
[   99.508600] [<c0090238>] (irq_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[   99.515882] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[   99.523534] palmas-usb palmas_usb.7: USB cable is attached

Here's the change for palmas:

Quoted 7 lines

From: Felipe Balbi <[email protected]>
Subject: extcon: palmas: fix regression on extcon-next
All extcon users must rely on devm_extcon_dev_allocate() otherwise device registration will fail.
Signed-of-by Felipe Balbi <[email protected]>

Quoted 9 lines

Quoted 1 line
If you possible, I'd like you to test this patch[1] based on extcon-next branch.
I'll do that. I can't seem to find that patch in my inbox even though I'm in Cc.
One thing though, the current order of your next branch will create a non-bisectable history, you need to shuffle things around to avoid this not working spots.

I'm sorry about this mistake.

As you comment, I would have modified both extcon core and extcon provider driver on following patch[1].
[1]
[PATCHv2 1/9] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device
- https://lkml.org/lkml/2014/4/21/164

I'll solve bisectable history by sending new patchset(v3).

Thanks for your comment.
Chanwoo Choi

Felipe Balbi

author

2014-04-24 14:13 UTC #6 lore raw

Quoted 748 lines · Chanwoo Choi

Hi,

Quoted 735 lines · Felipe Balbi

Hi,

Quoted 732 lines · Chanwoo Choi

Hi Felipe,

Thanks for your test and review.

Quoted 653 lines · Felipe Balbi

Hi,

Quoted 637 lines · Felipe Balbi

Quoted 180 lines

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Quoted 5 lines

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!
Please fix that up ASAP.

After fixing (actually, hacking) the first problem:

drivers/extcon/extcon-class.c +0 -0

index 677c502..d1b74e8 100644

drivers/extcon/extcon-class.c int extcon_dev_register(struct extcon_dev *edev) · line 597

Quoted 5 lines

drivers/extcon/extcon-class.c +1 -1

@@ -594,7 +594,7 @@ int extcon_dev_register(struct extcon_dev *edev)
 	}
 	dev_set_name(&edev->dev, "%s", edev->name);
 
-	ret = device_add(&edev->dev);
+	ret = device_register(&edev->dev);

It is not bug.

edev = extcon_dev_allocate()

	{
		...
		device_initialize(&edev->dev) (line.683)
	}

ret = extcon_dev_register(edev)

	{
		...
		device_add(&edev->dev);
		...
	}

Quoted 32 lines

drivers/extcon/extcon-class.c +0 -0

 	if (ret) {
 		put_device(&edev->dev);
 		return ret;

another problem shows up when connecting the USB cable:

[   99.386598] INFO: trying to register non-static key.
[   99.391787] the code is fine but needs lockdep annotation.
[   99.397529] turning off the locking correctness validator.
[   99.403262] CPU: 1 PID: 757 Comm: irq/39-palmas Tainted: G        W     3.15.0-rc2-00041-g3019b77-dirty #315
[   99.413552] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[   99.421658] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[   99.429216] [<c05426b4>] (dump_stack) from [<c0085584>] (__lock_acquire+0x17c8/0x1bc0)
[   99.437498] [<c0085584>] (__lock_acquire) from [<c008617c>] (lock_acquire+0xa4/0x100)
[   99.445692] [<c008617c>] (lock_acquire) from [<c05486e0>] (_raw_spin_lock_irqsave+0x38/0x4c)
[   99.454530] [<c05486e0>] (_raw_spin_lock_irqsave) from [<c0462610>] (extcon_update_state+0x20/0x20c)
[   99.464084] [<c0462610>] (extcon_update_state) from [<c0462f6c>] (palmas_vbus_irq_handler+0x60/0xa4)
[   99.473640] [<c0462f6c>] (palmas_vbus_irq_handler) from [<c0091ce0>] (handle_nested_irq+0xa0/0x100)
[   99.483109] [<c0091ce0>] (handle_nested_irq) from [<c0368e20>] (regmap_irq_thread+0x17c/0x300)
[   99.492120] [<c0368e20>] (regmap_irq_thread) from [<c008ff20>] (irq_thread_fn+0x1c/0x40)
[   99.500586] [<c008ff20>] (irq_thread_fn) from [<c0090238>] (irq_thread+0x12c/0x188)
[   99.508600] [<c0090238>] (irq_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[   99.515882] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[   99.523534] palmas-usb palmas_usb.7: USB cable is attached

Here's the change for palmas:

Quoted 7 lines

From: Felipe Balbi <[email protected]>
Subject: extcon: palmas: fix regression on extcon-next
All extcon users must rely on devm_extcon_dev_allocate() otherwise device registration will fail.
Signed-of-by Felipe Balbi <[email protected]>

Quoted 9 lines

Quoted 1 line
If you possible, I'd like you to test this patch[1] based on extcon-next branch.
I'll do that. I can't seem to find that patch in my inbox even though I'm in Cc.
One thing though, the current order of your next branch will create a non-bisectable history, you need to shuffle things around to avoid this not working spots.

Quoted 6 lines

I'm sorry about this mistake.
As you comment, I would have modified both extcon core and extcon
provider driver on following patch[1]. [1]
[PATCHv2 1/9] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device
- https://lkml.org/lkml/2014/4/21/164

cool, I guess you need to find a way to still keep the old version around until all users are converted, then you can remove it on a following patch.

Quoted 1 line

I'll solve bisectable history by sending new patchset(v3).

alright, thank you. I tested your palmas change and it's working fine.

thanks

Signature · 1 line

balbi

Chanwoo Choi

maintainer

2014-04-24 05:31 UTC #7 lore raw

In reply to Felipe Balbi

Hi Felipe,

Thanks for your test and review.

Quoted 634 lines · Felipe Balbi

Hi,

Quoted 182 lines · Felipe Balbi

Hi Chanwoo,

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

Quoted 7 lines

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device
And the bug is very simple and affects *all* users of extcon class, which tells me that this big series switching over to devm_* resources wasn't tested at all. Originally extcon_dev_register() was calling device_register(&edev->dev) which will call device_initialize(dev) followed by device_add(dev).

This patchset add 'extcon_dev_allocate()' to allocate the memory of extcon device. So, extcon_dev_allocate() calls 'device_initialize(" before calling extcon_dev_register() and then extcon_dev_register() calls device_add() function as following.

edev = extcon_dev_allocate()

	{
		...
		device_initialize(&edev->dev) (line.683)
	}

ret = extcon_dev_register(edev)

	{
		...
		device_add(&edev->dev);
		...
	}

Quoted 4 lines

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!

First of all,
I tested this patchset both normal case and error case.
- test environment : 3.15-rc2 with merging extcon-next branch

But,
As you comment, after merged this patch, extcon provider drvier have to use both extcon_dev_allocate() and extcon_dev_register(). If only using extcon_dev_register(), will happen error as you comment.

Thanks,
Chanwoo Choi

Felipe Balbi

author

2014-04-24 06:45 UTC #8 lore raw

Hi,

Quoted 666 lines · Chanwoo Choi

Quoted 634 lines · Felipe Balbi

Hi,

Quoted 182 lines · Felipe Balbi

Hi Chanwoo,

I've been testing extcon-next to make sure USB3 on OMAP5 will work out of the box but I see a regression when I merge your tree on top of v3.15-rc2 + Tony's DT fixes.

Here's what I see (trimmed):

[    1.805870] palmas 0-0048: Muxing GPIO 2, PWM 0, LED 0
[    1.812516] ------------[ cut here ]------------
[    1.817387] WARNING: CPU: 0 PID: 6 at include/linux/kref.h:47 kobject_get+0x64/0x78()
[    1.817691]  mmcblk0boot1: unknown partition table
[    1.830601] Modules linked in:
[    1.833827] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    1.843333] Workqueue: deferwq deferred_probe_work_func
[    1.848728]  mmcblk0boot0: unknown partition table
[    1.853928] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    1.862086] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    1.869667] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    1.878181] [<c0040928>] (warn_slowpath_common) from [<c00409e8>] (warn_slowpath_null+0x1c/0x24)
[    1.887421] [<c00409e8>] (warn_slowpath_null) from [<c02d50c4>] (kobject_get+0x64/0x78)
[    1.895837] [<c02d50c4>] (kobject_get) from [<c0350188>] (device_add+0x18/0x520)
[    1.903629] [<c0350188>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    1.912145] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    1.921847] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    1.931453] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    1.940333] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    1.949664] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    1.958634] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    1.967003] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    1.975387] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    1.983678] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    1.993155] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.003818] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.013399] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.022606] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.031722] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.040715] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.049098] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.057482] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.065774] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.073885] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.082903] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.091925] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.100582] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.109883] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.118823] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.127194] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.135584] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.144975] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.154545] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.163119] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.170695] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.178259] ---[ end trace 3006de6450234d28 ]---
[    2.183081] kobject 'palmas_usb' (eca58c38): tried to add an uninitialized object, something is seriously wrong.
[    2.193731] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.203201] Workqueue: deferwq deferred_probe_work_func
[    2.208687] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.216789] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.224357] [<c05426b4>] (dump_stack) from [<c02d5c28>] (kobject_add+0x88/0x98)
[    2.232014] [<c02d5c28>] (kobject_add) from [<c0350250>] (device_add+0xe0/0x520)
[    2.239758] [<c0350250>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.248235] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.257901] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.267467] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.276298] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.285591] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.294520] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.302905] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.311286] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.319583] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.329063] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.339725] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.349296] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.358496] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.367609] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.376523] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.384914] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.393301] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.401601] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.409707] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.418727] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.427741] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.436382] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.445680] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.454613] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.463001] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.471385] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.480772] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.490339] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.498906] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.506460] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.514023] ------------[ cut here ]------------
[    2.518870] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.526514] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.536076] Modules linked in:
[    2.539287] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.548753] Workqueue: deferwq deferred_probe_work_func
[    2.554223] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.562341] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.569911] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.578391] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.587502] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.595780] [<c02d5158>] (kobject_put) from [<c03502fc>] (device_add+0x18c/0x520)
[    2.603623] [<c03502fc>] (device_add) from [<c0462a5c>] (extcon_dev_register+0x48/0x104)
[    2.612103] [<c0462a5c>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.621762] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.631321] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.640161] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.649447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.658386] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.666757] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.675144] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.683441] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    2.692921] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    2.703575] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    2.713139] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    2.722341] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.731457] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.740380] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.748764] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.757135] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    2.765429] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    2.773549] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    2.782576] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    2.791597] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    2.800261] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    2.809560] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    2.818489] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    2.826865] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    2.835253] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    2.844637] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    2.854205] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    2.862778] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    2.870349] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    2.877911] ---[ end trace 3006de6450234d29 ]---
[    2.882734] ------------[ cut here ]------------
[    2.887573] WARNING: CPU: 0 PID: 6 at lib/kobject.c:670 kobject_put+0x80/0x90()
[    2.895209] kobject: 'palmas_usb' (eca58c38): is not initialized, yet kobject_put() is being called.
[    2.904765] Modules linked in:
[    2.907971] CPU: 0 PID: 6 Comm: kworker/u4:0 Tainted: G        W     3.15.0-rc2-00041-g3019b77 #308
[    2.917447] Workqueue: deferwq deferred_probe_work_func
[    2.922924] [<c0015110>] (unwind_backtrace) from [<c0011d6c>] (show_stack+0x10/0x14)
[    2.931033] [<c0011d6c>] (show_stack) from [<c05426b4>] (dump_stack+0x84/0x9c)
[    2.938606] [<c05426b4>] (dump_stack) from [<c0040928>] (warn_slowpath_common+0x6c/0x90)
[    2.947069] [<c0040928>] (warn_slowpath_common) from [<c004097c>] (warn_slowpath_fmt+0x30/0x40)
[    2.956187] [<c004097c>] (warn_slowpath_fmt) from [<c02d5158>] (kobject_put+0x80/0x90)
[    2.964483] [<c02d5158>] (kobject_put) from [<c0462abc>] (extcon_dev_register+0xa8/0x104)
[    2.973053] [<c0462abc>] (extcon_dev_register) from [<c0462b44>] (devm_extcon_dev_register+0x2c/0x68)
[    2.982718] [<c0462b44>] (devm_extcon_dev_register) from [<c04630c0>] (palmas_usb_probe+0x110/0x304)
[    2.992285] [<c04630c0>] (palmas_usb_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.001124] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.010423] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.019358] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.027746] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.036121] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.044418] [<c0350590>] (device_add) from [<c045a310>] (of_platform_device_create_pdata+0x6c/0x8c)
[    3.053893] [<c045a310>] (of_platform_device_create_pdata) from [<c045a418>] (of_platform_bus_create+0xdc/0x168)
[    3.064550] [<c045a418>] (of_platform_bus_create) from [<c045a5cc>] (of_platform_populate+0x5c/0xa0)
[    3.074124] [<c045a5cc>] (of_platform_populate) from [<c0373c78>] (palmas_i2c_probe+0x30c/0x584)
[    3.083338] [<c0373c78>] (palmas_i2c_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.092447] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.101381] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.109767] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.118147] [<c035206c>] (bus_probe_device) from [<c0350590>] (device_add+0x420/0x520)
[    3.126432] [<c0350590>] (device_add) from [<c0424020>] (i2c_new_device+0x12c/0x18c)
[    3.134547] [<c0424020>] (i2c_new_device) from [<c0424980>] (i2c_register_adapter+0x278/0x498)
[    3.143569] [<c0424980>] (i2c_register_adapter) from [<c04275c0>] (omap_i2c_probe+0x4a4/0x6d0)
[    3.152593] [<c04275c0>] (omap_i2c_probe) from [<c0354284>] (platform_drv_probe+0x18/0x48)
[    3.161249] [<c0354284>] (platform_drv_probe) from [<c0352b0c>] (driver_probe_device+0x110/0x22c)
[    3.170537] [<c0352b0c>] (driver_probe_device) from [<c03511a0>] (bus_for_each_drv+0x58/0x8c)
[    3.179472] [<c03511a0>] (bus_for_each_drv) from [<c03529c8>] (device_attach+0x74/0x8c)
[    3.187854] [<c03529c8>] (device_attach) from [<c035206c>] (bus_probe_device+0x88/0xb0)
[    3.196222] [<c035206c>] (bus_probe_device) from [<c03524ac>] (deferred_probe_work_func+0x64/0x94)
[    3.205611] [<c03524ac>] (deferred_probe_work_func) from [<c0058c70>] (process_one_work+0x1ac/0x4cc)
[    3.215174] [<c0058c70>] (process_one_work) from [<c0059b10>] (worker_thread+0x114/0x3b4)
[    3.223739] [<c0059b10>] (worker_thread) from [<c005f6f0>] (kthread+0xd4/0xf0)
[    3.231313] [<c005f6f0>] (kthread) from [<c000e3c8>] (ret_from_fork+0x14/0x2c)
[    3.238883] ---[ end trace 3006de6450234d2a ]---
[    3.243711] palmas-usb palmas_usb.7: failed to register extcon device
[    3.250493] palmas-usb: probe of palmas_usb.7 failed with error -22

Quoted 1 line

Any ideas ??

bisected down to:

commit 854b85057cc6b90a326b731174b6c6dbbf34222a

Author: Chanwoo Choi <[email protected]>
Date:   Mon Apr 21 19:46:51 2014 +0900

extcon: Add extcon_dev_allocate/free() to control the memory of extcon device

Signed-off-by Chanwoo Choi <[email protected]>

drivers/extcon/extcon-class.c +162 ~~-133~~

index f6df689..3e485bc 100644
@@ -558,6 +558,9 @@ static int create_extcon_class(void)
 
 static void extcon_dev_release(struct device *dev)
 {
+	struct extcon_dev *edev = dev_to_extcon_dev(dev);
+
+	kfree(edev);
 }
 
 static const char *muex_name = "mutually_exclusive";

@@ -576,7 +579,7 @@ static void dummy_sysfs_dev_release(struct device *dev)
  */
 int extcon_dev_register(struct extcon_dev *edev)
 {
-	int ret, index = 0;
+	int ret;
 
 	if (!extcon_class) {
 		ret = create_extcon_class();

@@ -584,80 +587,150 @@ int extcon_dev_register(struct extcon_dev *edev)
 			return ret;
 	}
 
-	if (edev->supported_cable) {
-		/* Get size of array */
-		for (index = 0; edev->supported_cable[index]; index++)
-			;
-		edev->max_supported = index;
-	} else {
-		edev->max_supported = 0;
+	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
+	if (IS_ERR_OR_NULL(edev->name)) {
+		dev_err(&edev->dev, "extcon device name is null\n");
+		return -EINVAL;
 	}
+	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (index > SUPPORTED_CABLE_MAX) {
-		dev_err(&edev->dev, "extcon: maximum number of supported cables exceeded.\n");
-		return -EINVAL;
+	ret = device_add(&edev->dev);
+	if (ret) {
+		put_device(&edev->dev);
+		return ret;
 	}
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
+#endif /* CONFIG_ANDROID */
 
-	edev->dev.class = extcon_class;
-	edev->dev.release = extcon_dev_release;
+	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
 
-	edev->name = edev->name ? edev->name : dev_name(edev->dev.parent);
-	if (IS_ERR_OR_NULL(edev->name)) {
-		dev_err(&edev->dev,
-			"extcon device name is null\n");
-		return -EINVAL;
+	dev_set_drvdata(&edev->dev, edev);
+	edev->state = 0;
+
+	mutex_lock(&extcon_dev_list_lock);
+	list_add(&edev->entry, &extcon_dev_list);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(extcon_dev_register);
+
+/**
+ * extcon_dev_unregister() - Unregister the extcon device.
+ * @edev:	the extcon device instance to be unregistered.
+ */
+void extcon_dev_unregister(struct extcon_dev *edev)
+{
+	mutex_lock(&extcon_dev_list_lock);
+	list_del(&edev->entry);
+	mutex_unlock(&extcon_dev_list_lock);
+
+	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
+		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
+				dev_name(&edev->dev));
+		return;
 	}
-	dev_set_name(&edev->dev, "%s", edev->name);
 
-	if (edev->max_supported) {
-		char buf[10];
-		char *str;
-		struct extcon_cable *cable;
+	device_unregister(&edev->dev);
 
-		edev->cables = kzalloc(sizeof(struct extcon_cable) *
-				       edev->max_supported, GFP_KERNEL);
-		if (!edev->cables) {
+#if defined(CONFIG_ANDROID)
+	if (switch_class)
+		class_compat_remove_link(switch_class, &edev->dev, NULL);
+#endif
+}
+EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+
+/*
+ * extcon_dev_allocate() - Allocate the memory of extcon device.
+ * @supported_cable:	Array of supported cable names ending with NULL.
+ *			If supported_cable is NULL, cable name related APIs
+ *			are disabled.
+ *
+ * This function allocates the memory for extcon device without allocating
+ * memory in each extcon provider driver and initialize default setting for
+ * extcon device.
+ *
+ * Return the pointer of extcon device if success or ERR_PTR(err) if fail
+ */
+struct extcon_dev *extcon_dev_allocate(const char **supported_cable)
+{
+	struct extcon_dev *edev;
+	int index, ret, count = 0;
+
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		pr_err("Failed to allocate the memory for extcon device\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	edev->max_supported = 0;
+	edev->supported_cable = supported_cable;
+	if (edev->supported_cable) {
+		for (count = 0; edev->supported_cable[count]; count++)
+			;
+		edev->max_supported = count;
+		if (count > SUPPORTED_CABLE_MAX) {
+			pr_err("Exceed max number of supported cables\n");
 			ret = -ENOMEM;
-			goto err_sysfs_alloc;
+			goto err;
 		}
-		for (index = 0; index < edev->max_supported; index++) {
-			cable = &edev->cables[index];
+	}
 
-			snprintf(buf, 10, "cable.%d", index);
-			str = kzalloc(sizeof(char) * (strlen(buf) + 1),
-				      GFP_KERNEL);
-			if (!str) {
-				for (index--; index >= 0; index--) {
-					cable = &edev->cables[index];
-					kfree(cable->attr_g.name);
-				}
-				ret = -ENOMEM;
+	edev->dev.class = extcon_class;
+	edev->dev.release = extcon_dev_release;
+	device_initialize(&edev->dev);
+	spin_lock_init(&edev->lock);
+
+	if (!edev->max_supported)
+		return 0;
+
+	edev->cables = kzalloc(sizeof(struct extcon_cable) *
+			       edev->max_supported, GFP_KERNEL);
+	if (!edev->cables) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
-				goto err_alloc_cables;
+	for (index = 0; index < edev->max_supported; index++) {
+		struct extcon_cable *cable = &edev->cables[index];
+		char buf[10];
+		char *str;
+
+		snprintf(buf, 10, "cable.%d", index);
+		str = kzalloc(sizeof(char) * (strlen(buf) + 1),
+			      GFP_KERNEL);
+		if (!str) {
+			for (index--; index >= 0; index--) {
+				cable = &edev->cables[index];
+				kfree(cable->attr_g.name);
 			}
-			strcpy(str, buf);
-
-			cable->edev = edev;
-			cable->cable_index = index;
-			cable->attrs[0] = &cable->attr_name.attr;
-			cable->attrs[1] = &cable->attr_state.attr;
-			cable->attrs[2] = NULL;
-			cable->attr_g.name = str;
-			cable->attr_g.attrs = cable->attrs;
-
-			sysfs_attr_init(&cable->attr_name.attr);
-			cable->attr_name.attr.name = "name";
-			cable->attr_name.attr.mode = 0444;
-			cable->attr_name.show = cable_name_show;
-
-			sysfs_attr_init(&cable->attr_state.attr);
-			cable->attr_state.attr.name = "state";
-			cable->attr_state.attr.mode = 0444;
-			cable->attr_state.show = cable_state_show;
+			ret = -ENOMEM;
+			goto err_alloc_cables;
 		}
+		strcpy(str, buf);
+
+		cable->edev = edev;
+		cable->cable_index = index;
+		cable->attrs[0] = &cable->attr_name.attr;
+		cable->attrs[1] = &cable->attr_state.attr;
+		cable->attrs[2] = NULL;
+		cable->attr_g.name = str;
+		cable->attr_g.attrs = cable->attrs;
+
+		sysfs_attr_init(&cable->attr_name.attr);
+		cable->attr_name.attr.name = "name";
+		cable->attr_name.attr.mode = 0444;
+		cable->attr_name.show = cable_name_show;
+
+		sysfs_attr_init(&cable->attr_state.attr);
+		cable->attr_state.attr.name = "state";
+		cable->attr_state.attr.mode = 0444;
+		cable->attr_state.show = cable_state_show;
 	}
 
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		char buf[80];
 		char *name;

@@ -703,59 +776,32 @@ int extcon_dev_register(struct extcon_dev *edev)
 		}
 		edev->attr_g_muex.name = muex_name;
 		edev->attr_g_muex.attrs = edev->attrs_muex;
-
 	}
 
-	if (edev->max_supported) {
-		edev->extcon_dev_type.groups =
-			kzalloc(sizeof(struct attribute_group *) *
-				(edev->max_supported + 2), GFP_KERNEL);
-		if (!edev->extcon_dev_type.groups) {
-			ret = -ENOMEM;
-			goto err_alloc_groups;
-		}
-
-		edev->extcon_dev_type.name = dev_name(&edev->dev);
-		edev->extcon_dev_type.release = dummy_sysfs_dev_release;
-
-		for (index = 0; index < edev->max_supported; index++)
-			edev->extcon_dev_type.groups[index] =
-				&edev->cables[index].attr_g;
-		if (edev->mutually_exclusive)
-			edev->extcon_dev_type.groups[index] =
-				&edev->attr_g_muex;
-
-		edev->dev.type = &edev->extcon_dev_type;
+	edev->extcon_dev_type.groups =
+		kzalloc(sizeof(struct attribute_group *) *
+			(edev->max_supported + 2), GFP_KERNEL);
+	if (!edev->extcon_dev_type.groups) {
+		ret = -ENOMEM;
+		goto err_alloc_groups;
 	}
 
-	ret = device_register(&edev->dev);
-	if (ret) {
-		put_device(&edev->dev);
-		goto err_dev;
-	}
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		ret = class_compat_create_link(switch_class, &edev->dev, NULL);
-#endif /* CONFIG_ANDROID */
-
-	spin_lock_init(&edev->lock);
-
-	RAW_INIT_NOTIFIER_HEAD(&edev->nh);
+	edev->extcon_dev_type.name = dev_name(&edev->dev);
+	edev->extcon_dev_type.release = dummy_sysfs_dev_release;
 
-	dev_set_drvdata(&edev->dev, edev);
-	edev->state = 0;
+	for (index = 0; index < edev->max_supported; index++)
+		edev->extcon_dev_type.groups[index] =
+			&edev->cables[index].attr_g;
+	if (edev->mutually_exclusive)
+		edev->extcon_dev_type.groups[index] =
+			&edev->attr_g_muex;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_add(&edev->entry, &extcon_dev_list);
-	mutex_unlock(&extcon_dev_list_lock);
+	edev->dev.type = &edev->extcon_dev_type;
 
-	return 0;
+	return edev;
 
-err_dev:
-	if (edev->max_supported)
-		kfree(edev->extcon_dev_type.groups);
 err_alloc_groups:
-	if (edev->max_supported && edev->mutually_exclusive) {
+	if (edev->mutually_exclusive) {
 		for (index = 0; edev->mutually_exclusive[index]; index++)
 			kfree(edev->d_attrs_muex[index].attr.name);
 		kfree(edev->d_attrs_muex);

@@ -765,36 +811,22 @@ err_muex:
 	for (index = 0; index < edev->max_supported; index++)
 		kfree(edev->cables[index].attr_g.name);
 err_alloc_cables:
-	if (edev->max_supported)
-		kfree(edev->cables);
-err_sysfs_alloc:
-	return ret;
+	kfree(edev->cables);
+err:
+	kfree(edev);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_register);
+EXPORT_SYMBOL_GPL(extcon_dev_allocate);
 
-/**
- * extcon_dev_unregister() - Unregister the extcon device.
- * @edev:	the extcon device instance to be unregistered.
- *
- * Note that this does not call kfree(edev) because edev was not allocated
- * by this class.
+/*
+ * extcon_dev_free() - Free the memory of extcon device.
+ * @edev:	the extcon device to free
  */
-void extcon_dev_unregister(struct extcon_dev *edev)
+void extcon_dev_free(struct extcon_dev *edev)
 {
 	int index;
 
-	mutex_lock(&extcon_dev_list_lock);
-	list_del(&edev->entry);
-	mutex_unlock(&extcon_dev_list_lock);
-
-	if (IS_ERR_OR_NULL(get_device(&edev->dev))) {
-		dev_err(&edev->dev, "Failed to unregister extcon_dev (%s)\n",
-				dev_name(&edev->dev));
-		return;
-	}
-
-	device_unregister(&edev->dev);
-
 	if (edev->mutually_exclusive && edev->max_supported) {
 		for (index = 0; edev->mutually_exclusive[index];
 				index++)

@@ -811,13 +843,10 @@ void extcon_dev_unregister(struct extcon_dev *edev)
 		kfree(edev->cables);
 	}
 
-#if defined(CONFIG_ANDROID)
-	if (switch_class)
-		class_compat_remove_link(switch_class, &edev->dev, NULL);
-#endif
-	put_device(&edev->dev);
+	if (edev)
+		put_device(&edev->dev);
 }
-EXPORT_SYMBOL_GPL(extcon_dev_unregister);
+EXPORT_SYMBOL_GPL(extcon_dev_free);
 
 static void devm_extcon_dev_unreg(struct device *dev, void *res)
 {

include/linux/extcon.h +15 -0

index 85a8a5b..20587ee 100644
@@ -179,6 +179,8 @@ struct extcon_specific_cable_nb {
 
 #if IS_ENABLED(CONFIG_EXTCON)
 
+#define dev_to_extcon_dev(d) container_of(d, struct extcon_dev, dev)
+
 /*
  * Following APIs are for notifiers or configurations.
  * Notifiers are the external port and connection devices.

@@ -250,6 +252,12 @@ extern int extcon_unregister_notifier(struct extcon_dev *edev,
 				      struct notifier_block *nb);
 
 /*
+ * Following APIs control the memory of extcon device.
+ */
+extern struct extcon_dev *extcon_dev_allocate(const char **cables);
+extern void extcon_dev_free(struct extcon_dev *edev);
+
+/*
  * Following API get the extcon device from devicetree.
  * This function use phandle of devicetree to get extcon device directly.
  */

@@ -353,5 +361,12 @@ static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev,
 {
 	return ERR_PTR(-ENODEV);
 }
+
+static inline struct extcon_dev *extcon_dev_allocate(const char **cables)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void extcon_dev_free(struct extcon_dev *edev) { }
 #endif /* CONFIG_EXTCON */
 #endif /* __LINUX_EXTCON_H__ */

here's full bisection log:

Quoted 7 lines

# first bad commit: [854b85057cc6b90a326b731174b6c6dbbf34222a] extcon: Add extcon_dev_allocate/free() to control the memory of extcon device
And the bug is very simple and affects *all* users of extcon class, which tells me that this big series switching over to devm_* resources wasn't tested at all. Originally extcon_dev_register() was calling device_register(&edev->dev) which will call device_initialize(dev) followed by device_add(dev).

edev = extcon_dev_allocate()

	{
		...
		device_initialize(&edev->dev) (line.683)
	}

ret = extcon_dev_register(edev)

	{
		...
		device_add(&edev->dev);
		...
	}

Quoted 4 lines

After this commit, extcon_dev_register() now calls device_add(&edev->dev) directly but never calls device_initialize() anywhere. Was this *ever* tested anywhere ????? I suppose not!

Quoted 8 lines

First of all,
I tested this patchset both normal case and error case.
- test environment : 3.15-rc2 with merging extcon-next branch
But,
As you comment, after merged this patch, extcon provider drvier have to use both extcon_dev_allocate() and extcon_dev_register(). If only using extcon_dev_register(), will happen error as you comment.

Sure thing, but if you're changing the API that much, you need to make sure other drivers are fixed up before merging stuff into next. What if I din't have anything pending to test ? This would've been merged in mainline.

Signature · 1 line

balbi