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| author | Heiner Kallweit <hkallweit1@gmail.com> | 2015-12-16 07:33:22 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-01-04 22:12:42 +0100 |
| commit | e0f03e87fc6f27a8af9896f430f2945b3b1664c0 (patch) | |
| tree | 609518455b06bfb95b74f7dcf1336244820f92b1 | |
| parent | a77060f07ffc6ac978e280e738302f3e5572a99e (diff) | |
| download | lwn-e0f03e87fc6f27a8af9896f430f2945b3b1664c0.tar.gz lwn-e0f03e87fc6f27a8af9896f430f2945b3b1664c0.zip | |
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.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | drivers/pnp/driver.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/pnp/driver.c b/drivers/pnp/driver.c index 153a493b5413..63452f20e3e9 100644 --- a/drivers/pnp/driver.c +++ b/drivers/pnp/driver.c @@ -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; } |