On 26/01/08 21:47 +0000, [EMAIL PROTECTED] wrote: > On Fri, 25 Jan 2008, Richard A. Smith wrote: > > > Chris Ball wrote: > > > >> >> Can I wake up 10 seconds from now? Is there a timer in any of the > >> >> hardware that is left running? > >> > >> > Yes, but the software does not support this yet. See bug #4606: > >> > http://dev.laptop.org/ticket/4606 > >> > >> We don't *use* the southbridge RTC wakeup, but it's not strictly true > >> that we don't support it. You can set your own wakeups easily: > >> > >> # rtcwake -s 120 > >> <after 30s, the laptop should suspend due to idleness> > >> <after another 90s, the laptop should wake itself> > >> > >> rtcwake is in the OLPC build already. > >> > >> - Chris. > > > > RTC wakeups have a chance of hitting #1835 because the EC cannot prevent > > the short cycle of the control line to the voltage regulator so we don't > > use them. Andres has discussed prohibiting RTC wakeups in kernel space > > but I suggested we put that in the "don't do that" category since he has > > higher priority stuff to worry about. > > > > The safe way to schedule a future wake up will be to use a EC timer. > > > > The framework for this exists but I don't have the kernel facing EC > > command plumbed yet. This timer will allow you to schedule a wakeup > > with about 10ms resolution up to 24 days in the future. > > what is the shortest time that a sleep (followed by a wakeup from the EC > timer) can be programmed? > > would it make sense to hack the kernel so that if all timers are set to > fire more than this far in the future it wakes a user task that can decide > to sleep
See also 'cpuidle' [1]. Jordan [1] - http://lwn.net/Articles/221791/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel