Re: [PATCH] ASoC: pcm512x: Mend accesses to the I2S_1 and I2S_2 registers

From: Peter Rosin
Date: Tue Sep 21 2021 - 09:30:50 EST


On 2021-09-21 14:01, Mark Brown wrote:
> On Tue, Sep 21, 2021 at 10:48:01AM +0200, Peter Rosin wrote:
>> On 2021-09-21 10:10, Peter Rosin wrote:
>
>> Ok, so the attached works for me as well. But I don't know if it's
>> appropriate to resume/suspend like that?
>
>> is:
>>
>> pcm512x 0-004c: Failed to set data format: -16
>>
>> The root cause is that the chip is in Powerdown mode when
>> pcm512x_set_fmt runs. So, bring the chip out of suspend for
>> the update of the format.
>
> How would this work if the device looses power while in suspend (eg, due
> to the regulators being software controllable)? If the data isn't being
> stored in the cache then it'll need to be stored somewhere else and
> restored on resume.

Right. Scratch v2. I'd go with the original patch. We have verified
that the original content of the I2S_1 register is the expected 0x02
(at least on one pcm5142) and besides, the four RSV bits are probably
don't care anyway.

Péter might have a different opinion?

Cheers,
Peter