backlight device, suspend/resume... [RANT]

[Carsten Haitzler (The Rasterman)]

On Fri, 11 Jul 2008 07:00:14 -0300 Werner Almesberger <werner at openmoko.org>
babbled:

> andrzej zaborowski wrote:
> > Another fun idea is: shut down and resume all the hardware manually
> > from the userspace daemon with sysfs writes.
> 
> I think this is the general direction we should aim for. Even if we
> can't go all the way, the trailblazing alone should be beneficial.
> 
> > It's a bit crazy though: you have to know what every
> > application on the system does.
> 
> Worse yet, you also have to make sure they don't try to touch devices
> you've just powered down.
> 
> > And you need your rootfs up, the kernel doesn't need it.
> 
> You mean for /dev ? That could be kept in RAM. The power daemon can
> just mlock itself, so it doesn't need to page in from the executable.

not sure we need to get too exotic. we can identify a minimal core that is "cpu"
or "system". this minimal core is what allows apps to execute safely (ie ram,
cpu, filesystem (the device it's on). not accounting for things like nfs mounts
etc. - but you get the idea. a small core that is always brought up together
and put to bed together).

-- 
Carsten Haitzler (The Rasterman) <raster at openmoko.org>