Initialization of musb on board-omap2beagle fails in platform_driver_probe

DISCUSSION Ben Gamari 3 participants 3 messages Mar 26, 2011 – Mar 28, 2011

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Ben Gamari

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2011-03-26 23:42 UTC #0 lore raw

Today I've had a very frustrating time trying to bring up a BeagleBoard (arch/arm/mach-omap2/board-omap2beagle.c) with the 2.6.38 kernel. Unfortunately musb has been giving me great difficulties,

 # modprobe g_ether
[   25.276855] usb_gadget_probe_driver 1815: usb_gadget_probe_driver, no dev??
modprobe: Failed to load module g_ether: No such device.

After a great deal of printking, I've determined that the error is coming from platform_driver_probe (platform.c:499). The code in question appears to be a check ensuring that any devices being probe were first registered. When the musb-hdrc module is probed, this check seems to fail with code = 1 and list_empty(&drv->driver.p->klist_devices.k_list) = 1.

What exactly is this check supposed to accomplish? Why would it fail during musb initialization? The relevant call path is,

kernel_init -> do_one_initcall -> musb_init -> platform_driver_probe

Both musb_init and platform_driver_probe return with -19. As far as I can tell, the board's init_machine successfully calls usb_musb_init from omap3_beagle_init, so the device should be registered well before arriving in musb_init.

Any ideas would be greatly appreciated. Cheers,

- Ben

Felipe Balbi

2011-03-28 08:37 UTC #1 lore raw

Hi,

Quoted 2 lines · Ben Gamari

Today I've had a very frustrating time trying to bring up a BeagleBoard (arch/arm/mach-omap2/board-omap2beagle.c) with the 2.6.38

there's no board-omap2beagle

Quoted 6 lines

kernel. Unfortunately musb has been giving me great difficulties,

 # modprobe g_ether
[   25.276855] usb_gadget_probe_driver 1815: usb_gadget_probe_driver, no dev??
modprobe: Failed to load module g_ether: No such device.

Quoted 6 lines

After a great deal of printking, I've determined that the error is coming from platform_driver_probe (platform.c:499). The code in question appears to be a check ensuring that any devices being probe were first registered. When the musb-hdrc module is probed, this check seems to fail with code = 1 and list_empty(&drv->driver.p->klist_devices.k_list) = 1.

looking at your .config from previous mail, it's wrong. You're trying to use am35x glue layer while you be using omap2430, just change:

- CONFIG_USB_MUSB_AM35X=y
+ # CONFIG_USB_MUSB_AM35X is not set
+ CONFIG_USB_MUSB_OMAP2PLUS=y

Signature · 1 line

balbi

Ben Gamari

2011-03-28 14:43 UTC #2 lore raw

Quoted 8 lines · Felipe Balbi

Hi,
Quoted 2 lines · Ben Gamari
Today I've had a very frustrating time trying to bring up a BeagleBoard (arch/arm/mach-omap2/board-omap2beagle.c) with the 2.6.38
there's no board-omap2beagle

My apologies, s/omap2/omap3.

Quoted 13 lines

Quoted 6 lines
kernel. Unfortunately musb has been giving me great difficulties,
 # modprobe g_ether
[   25.276855] usb_gadget_probe_driver 1815: usb_gadget_probe_driver, no dev??
modprobe: Failed to load module g_ether: No such device.
Quoted 6 lines
After a great deal of printking, I've determined that the error is coming from platform_driver_probe (platform.c:499). The code in question appears to be a check ensuring that any devices being probe were first registered. When the musb-hdrc module is probed, this check seems to fail with code = 1 and list_empty(&drv->driver.p->klist_devices.k_list) = 1.

Quoted 3 lines

looking at your .config from previous mail, it's wrong. You're trying to use am35x glue layer while you be using omap2430, just change:

Alright, fair enough. The mishmash of IP found in these ARM devices can make it very difficult to determine the correct configuration at times. Thanks for your help!

- Ben