Re: [PATCH] ALSA: hda/realtek: Fix pop noise on ALC225

[Takashi Iwai]

On Wed, 11 Mar 2020 07:13:28 +0100,
Kai-Heng Feng wrote:
> 
> Commit 317d9313925c ("ALSA: hda/realtek - Set default power save node to
> 0") makes the ALC225 have pop noise on S3 resume and cold boot.
> 
> So partially revert this commit for ALC225 to fix the regression.
> 
> Fixes: 317d9313925c ("ALSA: hda/realtek - Set default power save node to 0")
> BugLink: https://bugs.launchpad.net/bugs/1866357
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> ---

Hrm, it's rather surprising.  The power_save_node was thought to be a
cause of the pop noise, but in this case it fixes.  It's interesting
because this codec chip has no loopback mixer, and the connection is
directly from DAC to pin, so in theory, it shouldn't be influenced
from other nodes.

Anyways, a slight concern is that this might cause a regression on
another machine.  But who knows, maybe the influence is very limited.
Let's apply it and see what happens.


thanks,

Takashi