linux-kernel - Re: [PATCH] ALSA: hda/intel: Add quirk for TongFang devices with pop noise

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Date:   Wed, 11 May 2022 15:58:03 +0200
From:   Werner Sembach <wse@...edocomputers.com>
To:     Takashi Iwai <tiwai@...e.de>
Cc:     alsa-devel@...a-project.org, kai.vehmanen@...ux.intel.com,
        linux-kernel@...r.kernel.org, imre.deak@...el.com,
        pierre-louis.bossart@...ux.intel.com, tiwai@...e.com
Subject: Re: [PATCH] ALSA: hda/intel: Add quirk for TongFang devices with pop
 noise

Am 11.05.22 um 15:41 schrieb Takashi Iwai:
> On Wed, 11 May 2022 15:38:28 +0200,
> Werner Sembach wrote:
>> When audio stops playing and sometimes when it starts playing, there is an
>> audible "pop" noise when using headphones on most Tongfang GMxMxxx,
>> GKxNxxx, GMxZxxx, GMxTxxx, and GMxAxxx devices.
>>
>> Disabling power saving for the Realtek codec fixes this noise. Presumably
>> it is triggered on some power event in the audio circuit.
>>
>> Signed-off-by: Werner Sembach <wse@...edocomputers.com>
>> Cc: stable@...r.kernel.org
> Usually this denylist is a last resort if any other methods never
> helped.  Is it the case?

I also tried setting codec->power_save_node = 0; in a patch_realtek.c quirk.

static void alc274_fixup_pop_noise(struct hda_codec *codec, const struct
hda_fixup *fix, int action)
{
       codec->power_save_node = 0;
}

That initially seemed to work, but when I tested it again a day later
after a fresh install, it didn't anymore. I don't know what is
different. On the install before, I did some debugging with boot
parameters and other stuff, cant reproduce anymore what exactly.

I took the line from alc274_fixup_bind_dacs which fixes the pop noise
when applied to the devices, but does a lot of random other stuff too
not meant for the device.

I think I only ever warm rebooted when trying other fixes including that
one, maybe that's the reason for the different behavior a day later ..

Kind Regards,

Werner Sembach

>
>
> thanks,
>
> Takashi