Re: [PATCH] PM: sleep: core: Resume suspended device if direct-complete is disabled

From: Takashi Iwai
Date: Thu Jan 28 2021 - 03:21:44 EST


On Thu, 28 Jan 2021 09:15:10 +0100,
Kai-Heng Feng wrote:
>
> On Thu, Jan 28, 2021 at 4:09 PM Takashi Iwai <tiwai@xxxxxxx> wrote:
> >
> > On Thu, 31 Dec 2020 07:03:19 +0100,
> > Kai-Heng Feng wrote:
> > >
> > > HDA controller can't be runtime-suspended after commit 215a22ed31a1
> > > ("ALSA: hda: Refactor codjc PM to use direct-complete optimization"),
> > > which enables direct-complete for HDA codec.
> > >
> > > The HDA codec driver doesn't expect direct-complete will be disabled
> > > after it returns a positive value from prepare() callback. So freeze()
> > > is called directly when it's runtime-suspended, breaks the balance of
> > > its internal codec_powered counting.
> > >
> > > So if a device is prepared for direct-complete but PM core breaks the
> > > assumption, resume the device to keep PM operations balanced.
> > >
> > > Fixes: 215a22ed31a1 ("ALSA: hda: Refactor codec PM to use direct-complete optimization")
> > > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> >
> > Kai-Heng, is this fix still needed for 5.11?
>
> No it's not needed anymore because "ALSA: hda: Balance runtime/system
> PM if direct-complete is disabled" is in place.
>
> >
> > The description mentions about HD-audio controller, while the recent
> > revert was the HD-audio codec, so I suppose it's still affected?
>
> Not affected anymore if above mentioned patch is applied.

OK, thanks for clarification!


Takashi