From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takashi Iwai <tiwai@suse.de>
Subject: Re: Re: power management in alsa
Date: Thu, 26 Jul 2007 12:04:19 +0200
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References: <200707251436.59156.ak@suse.de> <s5hejiwwsfn.wl%tiwai@suse.de>
	<20070725184149.GA10173@ucw.cz>
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To: Pavel Machek <pavel@ucw.cz>
Cc: linux-pm@lists.linux-foundation.org, Andi Kleen <ak@suse.de>, perex@suse.cz
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At Wed, 25 Jul 2007 18:41:50 +0000,
Pavel Machek wrote:
> 
> Hi!
> 
> > > I noticed ALSA hda seems to only change PCI power management states
> > > of the sound devices on suspend/resume. Is there a reason the device
> > > cannot be automatically suspended when nobody has sound opened? 
> > 
> > I made once the automatic power-control patch for hd-audio, but it was
> > possibly racy and a bit messy implementation, so I abandoned it.
> > Since then, no one has worked on this issue.
> 
> IIRC that patch saved .3W, which is quite significant -- about half of
> spinning harddrive. I'd say it is worth the effort.

OK, then I'll take a look again (and try reimplementing a bit better :)


thanks,

Takashi