[PATCH v3] driver core / PM: Add PM domain callbacks for device setup/cleanup

Greg Kroah-Hartman gregkh at linuxfoundation.org
Sun Mar 22 04:46:31 PDT 2015

On Sat, Mar 21, 2015 at 02:00:24AM +0100, Rafael J. Wysocki wrote:
> On Friday, March 20, 2015 01:59:27 PM Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
> > 
> > If PM domains are in use, it may be necessary to prepare the code
> > handling a PM domain for driver probing.  For example, in some
> > cases device drivers rely on the ability to power on the devices
> > with the help of the IO runtime PM framework and the PM domain
> > code needs to be ready for that.  Also, if that code has not been
> > fully initialized yet, the driver probing should be deferred.
> > 
> > Moreover, after the probing is complete, it may be necessary to
> > put the PM domain in question into the state reflecting the current
> > needs of the devices in it, for example, so that power is not drawn
> > in vain.  The same should be done after removing a driver from
> > a device, as the PM domain state may need to be changed to reflect
> > the new situation.
> > 
> > For these reasons, introduce new PM domain callbacks, ->activate,
> > ->sync and ->dismiss called, respectively, before probing for a
> > device driver, after the probing has completed successfully and
> > if the probing has failed or the driver has been removed.
> > 
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
> > ---
> > 
> > One more update taking Dmitry's comments into account and fixing an
> > overoptimization bug spotted by Ulf.
> > 
> > And this actually contains the patch this time (clicked on "Send" too
> > early last time, sorry about that).
> Hi Greg,
> Since everybody seems to like this one, do you have any objectctions against it?
> If not, would it be a problem if I queued it up for 4.1?

No problem, nice cleanup:

Acked-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>

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