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

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Date:   Thu, 12 May 2022 20:08:41 +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 16:09 schrieb Takashi Iwai:
> On Wed, 11 May 2022 15:58:03 +0200,
> Werner Sembach wrote:
>> 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.
> power_save_node is already 0 as default for patch_alc269(), so it must
> be irrelevant.
>
>> 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.
> It's only one thing, there are tons of different fixes :)
> alc274_fixup_bind_dacs() rather specifies the routing so that the
> speaker is connected to the preferred DAC.
>
> Many click noises come from the default pin shut-up behavior.  You
> can disable it or change it in other way.  Also, setting
> auto_mute_via_amp may influence on such behavior (that is included in
> alc274_fixup_bind_dacs()).
>
> Note that many quirks can be enabled even without compiling but via
> the codec patch loading (using hints).
>
>
> thanks,
>
> Takashi

Found a quirk in patch_realtek.c with the same effect as the
power_save=0 and 2 more affected subsystem ids. Patch send as v2.

Kind Regards,

Werner