Re: Regression in -git / [PATCH] i2c-i801.c: don't pci_disable_device() after it was just enabled

[Daniel Ritz <daniel.ritz-ml@swissonline.ch>]

hi

On Thursday 29 June 2006 14.04, Jean Delvare wrote:
> Hi Daniel,
> 
> I see that your patch was already merged, but I would like to reply
> anyway.
> 
> > [PATCH] i2c-i801.c: don't pci_disable_device() after it was just enabled
> > 
> > Commit 02dd7ae2892e5ceff111d032769c78d3377df970:
> > 	[PATCH] i2c-i801: Merge setup function
> > has a missing return 0 in the _probe() function. this means the error
> > path is always executed and pci_disable_device() is called even when
> > the device just got successfully enabled.
> 
> Oops, good catch, thanks. I'm quite ashamed for letting this go
> through :(
> 
> > having the SMBus device disabled makes some systems (eg. Fujitsu-Siemens
> > Lifebook E8010) hang hard during power-off.
> > 
> > Intead of reverting the whole commit this patch fixes it up:
> > - don't ever call pci_disable_device(), also not in the _remove() function
> >   to avoid hangs
> 
> This is weird, and would certainly deserve additional investigation.
> Disabling the PCI device when we no more need it is the right thing to
> do and almost all pci drivers do that by now - except I2C bus drivers,

basically i agree, but...

> this is the first one I was attempting to convert.
> 
> Do you have any idea why disabling the SMBus causes the problem you
> observe? Could be that your BIOS attempts to use the SMBus at power

no idea. the last message that is display is "Shutdown: hda" then the
cursor blinks for 2 more seconds, then complete freeze. also enabling
all the debugging options in driver model, pm, i2c does not give me anything
more (it should...the messages during boot are there)...

> down time, but I wonder what for. Do you have anything special on this
> SMBus? Proprietary EEPROM? Real-time clock? I have two laptops using
> this driver (one Sony, one Dell) and none exhibited the problem you
> described.

sensors-detect says that there is the smartbattery thingy connected...
maybe the BIOS is querying the battery? dunno...

anyway i'll try again to find out what's causing the hang...

rgds
-daniel