Power button behaviour

Michael 'Mickey' Lauer mickey at openmoko.org
Mon Oct 20 00:06:13 CEST 2008

Am Sunday 19 October 2008 23:01:49 schrieb Mike (mwester):
> [cc'ing the kernel list, as this is pertinent to the kernel and recent
> discussion on that list]
> Olivier Fauchon wrote:
> > Hello.
> >
> >
> > Sometimes, I can't hard poweroff my GTA02 by "holding power down for
> > 10s" : ex when phone is really crashed or during boot (That's boring to
> > remove battery)
> >
> > Could you tell me why this situation occurs ? Pressing power 10s+ is an
> > hardware reboot, isn't it ? this should power down the phone in any
> > circonstances, without OS control ?
> It is "hardware" on the GTA01 (handled by the power-management chip),
> but it is done by the OS on the GTA02.  So for it to be able to power
> down the phone, at least some portion of the operating system needs to
> still be functional.
> > Can I change this 10s delay ? It's too long for me . 5s is good (like
> > for most of mobiles phones)
> Since it's done in software, it can be changed - it would require a
> modification to kernel source code and a rebuild of the kernel.  The big
> concern I have on that is that if I recall correctly, entering suspend
> manually on the FSO distro requires that you hold the power button down
> for nearly 4 seconds -- this would be awfully close to the 5 second
> emergency powerdown! 

2 seconds should be enough in ms3. Now that you did the patch to swallow the 
button presses on wakeup, I'm glad to add a new rule into the rules.yaml that 
will no longer need any holding of the button -- any short press will do the 
job then.


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