[alsa-devel] [PATCH v2] ASoC: max98090: save and restore SHDN when changing sensitive registers

[Marek Szyprowski]

Hi Mark,

On 20.12.2019 13:01, Mark Brown wrote:
> On Fri, Dec 20, 2019 at 10:05:52AM +0100, Marek Szyprowski wrote:
>> On 20.12.2019 09:28, Marek Szyprowski wrote:
>>> I've tried initially to cherry-pick it to v5.4, but the the code
>>> didn't compile due to lack of some macros, so I've gave up trying. I
>>> will check that now and backport needed macros too if you think this
>>> would help.
>> Same issue. I've tried backporting it to each kernel release: 5.4, 5.3,
>> 5.2, 5.1 and 5.0 (with additional backporting "ASoC: core: add
>> SND_SOC_BYTES_E" and "ASoC: Define a set of DAPM pre/post-up events").
>> In all cases the lockdep warning and oops is the same. Backporting to
>> v4.9 requires more changes to get it even compiled, so I gave up.
> OK, thanks - that's definitely not the recent refactorings then but
> something that's been a problem for a long time.  I'm surprised nobody
> else ran into anything if that's the case...

It took me a while to get back into this issue and investigate it in 
details. It turned out to be an incorrect helper to get component object 
in max98090_dapm_put_enum_double() function. Following patches: 
https://lkml.org/lkml/2020/1/8/358 fix this and (independent) lockdep 
issues.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland