Re: [Replacement][PATCH 2/6] PM / Domains: Fix hibernation restore of devices, v2

[Simon Horman <horms@verge.net.au>]

On Tue, Mar 13, 2012 at 10:32:42PM +0100, Rafael J. Wysocki wrote:
> On Tuesday, March 13, 2012, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rjw@sisk.pl>
> > 
> > During resume from hibernation pm_genpd_restore_noirq() has to
> > deal with software state left by pm_genpd_suspend_noirq() and
> > unknown hardware state (the boot kernel may leave all PM domains and
> > devices in arbitrary states).  For this reason, make it attempt to
> > power cycle each domain when before resuming its first device to
> > possibly get rid of any unwanted hardware state that may interfere
> > with genpd_start_dev() later on.
> > 
> > Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> 
> I realized that this wasn't a good idea because of patch [3/6] (we
> can't power cycle domains containing "always on" devices), so I
> decided to only fix the really broken things in pm_genpd_restore_noirq().
> 
> Of course, patch [3/6] also needs to be updated on top of the below to
> avoid starting "always on" devices in pm_genpd_restore_noirq() (it has
> to assume that they will be "always on" in the boot kernel too, but that
> seems to be a reasonable expectation).
> 
> Please note that those changes only affect resume from hibernation, so
> they don't invalidate the testing that has already been carried out.

Hi Rafael,

sorry for such a naeive question, but if I was to test
hibernate on the Mackerel how would I achieve resume?
Is there a button I should press?