[Pm-utils] Restore state around suspend/resume

[Dan Nicholson]

On Sun, Nov 30, 2008 at 1:01 AM, Takashi Iwai <tiwai at suse.de> wrote:
> At Sat, 29 Nov 2008 12:40:02 -0800,
> Dan Nicholson wrote:
>>
>> Hi,
>>
>> Currently, suspending the computer via pm-suspend (as done from HAL),
>> causes the ALSA state to be stored and restored via alsactl. Here's
>> what the hook looks like:
>>
>> http://cgit.freedesktop.org/pm-utils/tree/pm/sleep.d/65alsa
>>
>> Is this still necessary on recent kernels? Is there a list of drivers
>> which properly maintain state across suspend/resume? We're trying to
>> cut down on the amount of work done in userspace which slows down
>> suspend cycles.
>
> The all drivers with PM support should have do store/restore the
> mixer states.  For such drivers, calling alsactl is just a waste of
> time.

Thanks. Which drivers don't have PM support?

> I don't know who introduced it, but maybe it was a workaround...

Yeah, I'm sure it was a workaround, but we're trying to get rid of the
unnecessary ones now.

--
Dan