[regression] Headphone output gets unproperly powered down - Mi Notebook Pro 2020 (ALC256) (fwd of b.k.o bug #215484; starting with 5.14.14)

[Thorsten Leemhuis]

Hi, this is your Linux kernel regression tracker. Top-posting for once,
to make this easily accessible to everyone.

Could anybody please finally look into this bisected regression from
5.14.13 to 5.14.14 (f8d3c17e1c37 ("ALSA: hda/realtek - ALC236 headset
MIC recording issue")) that according to a recent bugzilla comment from
reporter is still present in recent 5.16 kernels?

Ciao, Thorsten

On 12.01.22 08:15, Thorsten Leemhuis wrote:
> 
> Hi, this is your Linux kernel regression tracker speaking.
> 
> I'm forwarding a regression reported in bugzilla.kernel.org to the list,
> to make sure all parties interested in this are aware of it. The
> reporter is CCed. Not CCing the stable list in this case, as 5.14 is EOL
> already.
> 
> https://bugzilla.kernel.org/show_bug.cgi?id=215484
> 
>> With headphones (or an auxiliary jack) plugged in, the audio output
>> is fine when anything is playing, but when that's stopped a loud pop
>> can be heard after some seconds and if the jack is connected to an
>> external amplifier it gets really noisy. Everything gets back to
>> normal whenever audio playback is resumed, although with another loud
>> pop at the start.
>>
>> This has been happening since kernel 5.14.14, whereas 5.14.13 is
>> fine. I suspect it has to do with the ALC256 mute logic implemented
>> in that version
>> (https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/diff/sound/pci/hda/patch_realtek.c?id=v5.14.14&id2=v5.14.13)
>>
>> OS: Fedora Linux 35 Kernel: 5.16.0-60 Vanilla Hardware: Xiaomi Mi
>> Notebook Pro Enhanced 2020 (i7 10510U, ALC256)
> 
> Ciao, Thorsten
> 
> #regzbot introduced v5.14.13..v5.14.14
> #regzbot link: https://bugzilla.kernel.org/show_bug.cgi?id=215484
> #regzbot from: Emanuele Melzi <itsbytebites at tutanota.com>