[RFC PATCH 2/3] ASoC: Intel: bdw-rt5677: fix module load/unload issues

[Pierre-Louis Bossart]

> This doesn't answer the question: why is the machine driver not
> requesting the GPIO on device model probe?

I *think* it's due to the need to use the codec component->dev, which is 
only available with the dailink callbacks - not on platform device probe 
which ends with the card registration.

> 
>> The issue happens when running our test scripts, which do a set a rmmod in a
>> specific order: rmmod of the machine driver, then doing an rmmod of the
>> codec driver. Somehow the second fails with the 'module in use error'.
> 
>> It's probably because the devm_ release does not happen when the card is
>> unregistered and the machine driver resources released since we use the
>> component device. There might very well be a bug somewhere in the devm_
>> handling, I just don't have a clue how to debug this - and the .exit() makes
>> sense regardless in other cases unrelated to GPIOs.
> 
> So you've removed the driver which will have unbound the device but devm
> actions don't seem to have fired?  That seems worrying...

Well, the devm uses the component device, not the card device, so when 
removing the machine driver nothing should happen. The problem seems to 
be in the removal of the codec and component drivers.

We tried to use the card device instead but then the gpiod_get fails.