From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: Re: power management in alsa Date: Wed, 25 Jul 2007 18:41:50 +0000 Message-ID: <20070725184149.GA10173@ucw.cz> References: <200707251436.59156.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Takashi Iwai Cc: linux-pm@lists.linux-foundation.org, Andi Kleen , perex@suse.cz List-Id: linux-pm@vger.kernel.org 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. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html