Using RTC for wake up

[Richard Purdie]

On Wed, 2008-07-30 at 16:24 +0200, Holger Freyther wrote:
> On Wednesday 30 July 2008 15:44:06 Sven Klomp wrote:
> > On Wednesday 30 July 2008 13:57:29 Holger Freyther wrote:
> > > On Wednesday 30 July 2008 11:22:44 Sven Klomp wrote:
> > > > some time ago I heard that the realtime clock can be used to wake up
> > > > the CPU from supend:
> > > > http://lists.openmoko.org/pipermail/community/2008-February/013366.html
> > > >
> > > > However, I couldn't find an further information. How can I set PMU to
> > > > wake up the CPU based on the clock? Is there any sysfs file?
> > >
> > > with ASU atd is running and you can schedule execution of programs by
> > > placing files in a certain directory (take a look at the code), otherwise
> > > use the plain linux rtc ioctl interface directly.
> >
> > And atd can also wake up from suspend? I couldn't find where the RTC is
> > set...
> 
> Yes, it will wakeup. This is how the alarm handling of the Qtopia clock is 
> done. The code of atd can be found here [1]. I'm not sure if it is the latest 
> available version...

See http://www.rpsys.net/openzaurus/temp/tests/rtctest.c for some
example alarm usage code.

Cheers,

Richard