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Subject: Re: [PATCH 1/8] PM: Opportunistic suspend support.
From: Peter Zijlstra <peterz@infradead.org>
To: Florian Mickler <florian@mickler.org>
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Date: Wed, 26 May 2010 11:33:22 +0200
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On Wed, 2010-05-26 at 11:23 +0200, Florian Mickler wrote:

> There is polling, because the suspend manager in userspace doesn't have
> the whole picture. i.e. it doesn't know if a suspend will be
> successfull. 
> So for aggressive suspending as a powersave-feature you need to poll
> (i.e. retry upon failure). because you don't want to stay unsuspended. 

Clearly if it fails, there something to be done, right? So whoever does
the thing will communicate with the suspend manager that it's going to
do and has finished doing its thing, at which point it will try again.

That's event driven, not polled.

Also, if you want you can keep the kernel-side auto-suspend side, and
have the suspend manager clear on !0 and re-establish the auto-suspend
state on 0.

But you really don't need this device thingy.