Re: [PATCH] ASoC: codecs: wsa884x: allow sharing reset GPIO

From: Krzysztof Kozlowski
Date: Wed Oct 18 2023 - 08:58:08 EST


On 18/10/2023 14:56, Mark Brown wrote:
> On Wed, Oct 18, 2023 at 02:38:00PM +0200, Krzysztof Kozlowski wrote:
>> On 18/10/2023 14:35, Mark Brown wrote:
>
>>> How do the speakers coordinate?
>
>> They don't and that's the generic problem of many Linux drivers. Not
>> only this one, but others as well.
>
>> Device unbind (remove()) or runtime suspend of one speaker will affect
>> other speaker. I don't think any other drivers solved this, because this
>> is rather core's GPIO issue, thus I am not solving it here either. :(
>
> I'd expect that the GPIO users should coordiante directly rather than
> rely on the GPIO API to do the coordination for them - there aren't
> enough semantics in the GPIO itself to do much more except possibly
> provide discovery services (which would be nice). Look at how the
> regulator API manages multiple regulators sharing an enable GPIO for
> example, it adds an additional layer of reference counting when it
> identifies a shared GPIO.

OK, it is still regulator core, though. Not individual drivers problem.

Several other existing drivers have the same issue, so this should be
solved in a generic or shared way.

Best regards,
Krzysztof