[bug report] 'ASoC: Intel: haswell: Power transition refactor' and PulseAudio

[Pierre-Louis Bossart]

On 9/1/20 6:33 AM, Cezary Rojewski wrote:
> On 2020-08-31 11:55 PM, Christian Bundy wrote:
>> After upgrading to Linux 5.8 I discovered an audio issue on my device 
>> that was introduced in 8ec7d6043263ecf250b9b7c0dd8ade899487538a [0]. I 
>> used 'git bisect' to identify the commit that introduced the bug and 
>> have confirmed that reverting the commit resolves the problem
>>
>> Reproduction:
>>
>> 1. Play any audio via PulseAudio.
>> 2. Observe that the audio output is fuzzy and choppy.
>>
>> I can use programs like mpv to play audio without PulseAudio, and the 
>> audio is fine, but as soon as I open a process that uses PulseAudio it 
>> will ruin the audio output for all processes (including mpv) until I 
>> reboot.
>>
>> I'm using a 2015 Chromebook Pixel ("Samus") and have confirmed this 
>> problem with a friend who has the same device.
>>
>> Is there anything I can do to help debug this instead of sending a 
>> patch to revert the commit?
>>
> 
> Hello Christian,
> 
> Thank you for report! Issue is a known one to us and has already been 
> addressed by:
> 
>      [PATCH v4 00/13] ASoC: Intel: Catpt - Lynx and Wildcat point
>      https://www.spinics.net/lists/alsa-devel/msg113762.html
> 
> waiting for final dependency to be merged (Andy's resource-API changes, 
> as Mark already added the SPI ones) so v5 with review changes can be 
> provided. Shouldn't be long before this gets merged. As consequence, 
> /haswell/ ceases to exist.

That leaves people with no working sound for 5.8 and 5.9.

> Basically, once power-cycle (D0 -> D3 -> D0 transition flow) had been 
> fixed, more - previously hidden - problems arisen. Instead of sending 
> 70+ patches to Mark refactoring existing code to recommended flow (+ 
> readability and performance improvements), replacement is provided along 
> with old code being removed entirely.
> 
> For now, if there's a possibility for you to modify your kernel, said 
> patch can be safely removed from your local repo. Note: following is the 
> outcome:
> - DMA init may occasionally fail on early boot (audio card won't be 
> present at all, requires reboot)
> - D0/D3 flow doesn't follow recommended sequence and thus power-saving 
> may be limited or non-existent
> Probably still better than permanently fuzzied audio..

Doesn't this mean that a revert is needed and applied to -stable for 5.8 
and 5.9?