[PATCH] pmac: Improve sleep code of tumbler driver

Colin Leroy colin at colino.net
Mon Apr 11 18:45:00 EST 2005

On Mon, 11 Apr 2005 18:34:34 +1000
Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote:

> On Mon, 2005-04-11 at 10:18 +0200, Colin Leroy wrote:
> > On Mon, 11 Apr 2005 12:00:54 +1000
> > Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote:
> > 
> > > This patch (applies on top of my previous one adding support for
> > > newer machines) improves the behaviour of the "tumbler/snapper"
> > > driver used on newer PowerMacs during sleep. It properly set the
> > > HW mutes to shut down amplifiers and does an analog shutdown of
> > > the codec. That might improve power consumption during sleep on a
> > > number of machines.
> > 
> > I suppose it also fixes the occasionnal loud static noise that
> > sometimes at wakeup, for example on iBook G4s. Good :)
> I don't know, tell me. I didn't know about this problem.

It was reported here:

I didn't personnaly report it because it was hard to track it down;
it'd happen about once in twenty resumes (more often when you're in a
quiet place with strangers around, evidently, according to Murphy's
law), and nothing unusual appeared in dmesg (even with SND_DEBUG, which
doesn't debug much on ppc anyway). I just got used to mute the ibook
before sending it to sleep.

> > Btw, do you know where patches land in this time of SCM change, when
> > it's not in -mm ?
> -mm :) Linus didn't restart merging things yet.

Ok, thanks. 

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