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To: marks@ripe.net
From: "M. Warner Losh" <imp@bsdimp.com>
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Subject: Re: Correct PCI suspend and resume operations
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In message: <20030610194132.GA4287@laptop.6bone.nl>
            Mark Santcroos <marks@ripe.net> writes:
: On Tue, Jun 10, 2003 at 09:15:05PM +0200, Mark Santcroos wrote:
: > > AFAICT, we don't common code for handling this and maybe there should
: > > be some rather than have each driver replicate this behaviour.
: > 
: > In general, that would of course be better. However, I don't know if the
: > PCI layer (in this case) always knows enough.
: > On the other side, if the device itself has to do some special things, the
: > PCI layer could at least do the generic stuff.
: 
: To be more precise, the suspend function should know the powerstate it is
: transitioning to. If it keeps context (D0-D2) it doesn't need to do much
: special, if it will loose context (D3) it should save the state at
: suspend, and restore the state at resume.

Sadly, in the current scheme, the device driver has no way of knowing
what the new power state is going to be.

Warner