pnp: respect PNP_DRIVER_RES_DO_NOT_CHANGE when detaching
Subsystems (2)
PATCH 1/1 pnp: respect PNP_DRIVER_RES_DO_NOT_CHANGE when detaching
I have a device (Nuvoton 6779D Super-IO IR RC with nuvoton-cir driver) which works after initial boot but not any longer if I unload and re-load the driver module.
Digging into the issue I found that unloading the driver calls pnp_disable_dev although the driver has flag PNP_DRIVER_RES_DO_NOT_CHANGE set. IMHO this is not right.
Let's have a look at the call chain when probing a device:pnp_device_probe
1. attaches the device
2. if it's not active and PNP_DRIVER_RES_DO_NOT_CHANGE is not set it gets activated
3. probes driver
I think pnp_device_remove should do it in reverse order and also respect PNP_DRIVER_RES_DO_NOT_CHANGE. Therefore:
1. call drivers remove callback
2. if device is active and PNP_DRIVER_RES_DO_NOT_CHANGE is not set disable it
3. detach device
The change works for me and sounds logical to me. However I don't know the pnp driver in detail so I might be wrong.
--- drivers/pnp/driver.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
drivers/pnp/driver.c +5 -1
@@ -74,7 +74,6 @@ void pnp_device_detach(struct pnp_dev *pnp_dev)if (pnp_dev->status ==PNP_ATTACHED ) pnp_dev->status =PNP_READY ;mutex_unlock (&pnp_lock); -pnp_disable_dev (pnp_dev); }static int pnp_device_probe (struct device *dev)
@@ -131,6 +130,11 @@ static int pnp_device_remove(struct device *dev) drv->remove (pnp_dev); pnp_dev->driver =NULL ; } + +if (pnp_dev->active && + (!drv || !(drv->flags &PNP_DRIVER_RES_DO_NOT_CHANGE ))) +pnp_disable_dev (pnp_dev); +pnp_device_detach (pnp_dev);return 0 ; }
Signature · 1 line
2.6.2
Rafael J. Wysocki
AppliedQuoted 22 lines · Heiner Kallweit
I have a device (Nuvoton 6779D Super-IO IR RC with nuvoton-cir driver) which works after initial boot but not any longer if I unload and re-load the driver module.
Digging into the issue I found that unloading the driver calls
pnp_disable_devalthough the driver has flagPNP_DRIVER_RES_DO_NOT_CHANGEset. IMHO this is not right.Let's have a look at the call chain when probing a device:
pnp_device_probe
1. attaches the device
2. if it's not active andPNP_DRIVER_RES_DO_NOT_CHANGEis not set it gets activated
3. probes driverI think
pnp_device_removeshould do it in reverse order and also respectPNP_DRIVER_RES_DO_NOT_CHANGE. Therefore:
1. call drivers remove callback
2. if device is active andPNP_DRIVER_RES_DO_NOT_CHANGEis not set disable it
3. detach device
Quoted 4 lines
The change works for me and sounds logical to me. However I don't know the pnp driver in detail so I might be wrong.
Signed-off-by Heiner Kallweit <[email protected]>
Applied, thanks!
Rafael