Re: New feature proposal "quickwakeup"

[Matthew Garrett <mjg59@srcf.ucam.org>]

On Fri, Nov 06, 2009 at 06:42:21PM +0100, Falempe Jocelyn wrote:

> In fact we are doing "retention" in idle and with the suspend path. It's
> specific to Android, with the global suspend and wakelock framework.
> When all wakelocks are released (ie screen is black, no running app),
> the phone goes to suspend, which freeze userspace and also suspend the
> device driver. This way you can choose the wakeup sources, and stay in
> suspend during a long time (a few hours). Without this, you have to
> track down all user space app that wakeup the phone, and it is hard to
> sleep more than a few second.

What's triggering the application wakeups? If it's just timeouts, can't 
you simply adjust the range timer slop so that the timeouts don't fire?

> The drawback is that when you want to wakeup, it takes a lot of time to
> unfreeze the userspace, and resume all the device driver. This is what
> this feature address (for low-level wakeup only).
> But as this patch is not Android specific, I think other platforms may
> use it too.

Yeah, I can certainly see the appeal if you have that constraint.

-- 
Matthew Garrett | mjg59@srcf.ucam.org