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SubjectRe: [alsa-devel] [PATCH v6 02/11] mfd: wcd934x: add support to wcd9340/wcd9341 codec

>>> Note these are the child devices of the MFD SLIMBus device.
>> Ah ok. I guess the creation of those child devices when the parent
>> SLIMbus device reports PRESENT initially if fine, it's the part where
>> you remove them if the device loses sync or gets powered off which is
>> odd. And I guess technically you could still have race conditions
>> where a child device starts a transaction just as the parent is no
>> longer attached to the bus.
> Losing power to SLIMBus device is very odd usecase and if it happens
> suggests that threre are bigger issues on the board design itself. This
> case should never happen. Even if it happens we would get timeout errors
> on every SLIMbus transactions.
>>>> I would however not remove the devices when the status is down but
>>>> only on an explicit .remove.
>>> Am open for suggestions but I would not like the child devices to
>>> talk on the bus once the SLIMbus device is down! Only way to ensure
>>> or make it silent is to remove.
>> it's as if you are missing a mechanism to forward the parent status to
>> the children so use remove() for lack of a better solution?
> That is true. This gives bit more control on the slave device lifecycle.
> Current solution works fine for now with less complexities across
> multiple drivers. I also agree that there is scope of improvement in
> future for this.

ok, makes sense, thanks for the answers. No further questions, so

Reviewed-by: Pierre-Louis Bossart <>

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