Re: [PATCH 4.19 67/77] ALSA: hda/via: Fix runtime PM for Clevo W35xSS

From: Takashi Iwai
Date: Wed Jan 13 2021 - 06:55:47 EST


On Wed, 13 Jan 2021 12:49:34 +0100,
Pavel Machek wrote:
>
> Hi!
>
> > From: Takashi Iwai <tiwai@xxxxxxx>
> >
> > commit 4bfd6247fa9164c8e193a55ef9c0ea3ee22f82d8 upstream.
> >
> > Clevo W35xSS_370SS with VIA codec has had the runtime PM problem that
> > looses the power state of some nodes after the runtime resume. This
> > was worked around by disabling the default runtime PM via a denylist
> > entry. Since 5.10.x made the runtime PM applied (casually) even
> > though it's disabled in the denylist, this problem was revisited. The
> > result was that disabling power_save_node feature suffices for the
> > runtime PM problem.
>
> From changelog it looks like we do not need this for 4.19.

The patch fixes the runtime PM problem that has existed for long time,
and that's the root cause of the issue mentioned in the Fixes tag
(that just papered over), so it still makes sense to backport as long
as it can be applied.


thanks,

Takashi