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From: "Cássio Gabriel Monteiro Pires" <cassiogabrielcontato@gmail.com>
To: Takashi Iwai <tiwai@suse.de>
Cc: Takashi Iwai <tiwai@suse.com>, Jaroslav Kysela <perex@perex.cz>,
	linux-sound@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ALSA: ac97: drop stale CMI9738 PCM-volume quirk
Date: Wed, 29 Apr 2026 10:04:38 -0300	[thread overview]
Message-ID: <f2636cc2-4e49-4a20-bc68-54c6ed830ecd@gmail.com> (raw)
In-Reply-To: <87h5ouos8m.wl-tiwai@suse.de>


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On 4/29/26 09:39, Takashi Iwai wrote:
> On Wed, 29 Apr 2026 14:05:31 +0200,
> Cássio Gabriel wrote:
>>
>> patch_cm9738() still carries an old comment claiming that CMI9738
>> has no PCM volume although AC97_PCM reacts, and then forces
>> AC97_HAS_NO_PCM_VOL.
>>
>> The CMI9738 datasheet documents register 0x18 as "PCM Out Vol"
>> with mute and left/right volume fields, so that old assumption is
>> not justified.
> 
> Well, that's actually the part the FIXME points to.  Although the spec
> shows the register is available and the chip reads out, the volume
> didn't seem reacting properly on the real hardware, as far as I
> remember correctly.
> 
> So, it's really doubtful whether it's safe to cut off this workaround
> just by reading the data sheet.

Yes, that matches what I suspected at first glance; I wanted to confirm
whether the datasheet was enough to revisit the old workaround.

> thanks,
> 
> Takashi

-- 
Thanks,
Cássio


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      reply	other threads:[~2026-04-29 13:04 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-29 12:05 [PATCH] ALSA: ac97: drop stale CMI9738 PCM-volume quirk Cássio Gabriel
2026-04-29 12:39 ` Takashi Iwai
2026-04-29 13:04   ` Cássio Gabriel Monteiro Pires [this message]

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