[alsa-devel] [PATCH 05/14] ALSA: pci: Remove superfluous snd_pcm_suspend*() calls

[Takashi Iwai]

On Wed, 16 Jan 2019 16:50:27 +0100,
Mark Brown wrote:
> 
> On Tue, Jan 15, 2019 at 09:42:09PM +0100, Takashi Iwai wrote:
> 
> > The last one has prepare and complete callbacks in addition to the
> > other standard PM calls.  And tm2_pm_preapre() stops sysclk and
> > complete() starts sysclk.  I don't understand why these are needed in
> > prepare and resume.  Can anyone explain?
> 
> AFAICT it's just making sure that they're available ASAP so they look
> always on to the rest of the system.

Well, but PM prepare is called before PM suspend call.  And the whole
ASoC suspend procedure (including PCM suspend, etc) is performed in
the PM suspend callback; i.e. we stop sysclk before doing anything
else...


Takashi