Availability of XO-1.5 ATest-2 machines
pgf at laptop.org
Mon Jul 20 15:27:53 EDT 2009
david at lang.hm wrote:
> On Mon, 20 Jul 2009, Paul Fox wrote:
> > chris wrote:
> > > Hi,
> > >
> > > > my understanding from watching discussions here was that when the
> > > > system went to sleep it powered down the display, because there
> > > > was no way to set a timer to wake the system up a little later to
> > > > then turn off the display.
> > >
> > > Your understanding is incorrect, I'm afraid. We do not power down the
> > > display going into idle-suspend.
> > >
> > but to be clear, david's right that once the laptop's in this
> > state there's no way to turn off the screen automatically later
> > on -- the system must be re-awakened with user input, and then
> > put to sleep in one of the usual (power switch or lid) ways.
> > this is simply a limitation of current s/w.
> is this just a software limitation? from the prior discussion I was under
> the impression that there was no timer that kept running once the main
> board goes to sleep, so you can't program anything to wake you up later to
> turn more stuff off. (not a problem normally, because normal systems don't
> have displays that can continue to show something once the main board is
rtcwake works fine, for these purposes, in later builds (post-767,
because rtc wakeups weren't distinguishable in the earlier kernels).
powerd uses this mechanism to accomplish screen (and system)
shutdown after sleep. (olpc-powerd is the alternate power
management package i wrote while i had some <cough> downtime from
OLPC earlier this year.)
paul fox, pgf at laptop.org
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