[RFD] How to tell ACPI drivers what the target sleep state is (was: Re: [PATCH 1/2] acpi choose sleep state help)

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Wednesday, 20 June 2007 08:18, Shaohua Li wrote:
> On Tue, 2007-06-19 at 13:52 +0200, Rafael J. Wysocki wrote:
> > On Tuesday, 19 June 2007 04:33, Shaohua Li wrote:
> > > Based on David's patch
> > > http://marc.info/?l=linux-acpi&m=117873972806360&w=2
> > > I slightly changed it.
> > > 
> > > Add a helper routine, which gets the sleep state of a ACPI device.
> > 
> > Is it going to work with the recent code ordering changes?  I mean,
> > acpi_pm_prepare() is now called after device_suspend() (and analogously for
> > the hibernation), so the target ACPI state is not known when the drivers'
> > .suspend() routines are being called.
> Not. Could pm_message_t have a member indicating the suspend state?

Well, I thought about that, but I did't know what people on linux-pm would
think about that.

Alternatively, we could introduce a pm_target() global PM operation that will
set the target sleep state for the entire system.

I think we should discuss that on linux-pm before any decision is made.

Greetings,
Rafael


-- 
"Premature optimization is the root of all evil." - Donald Knuth