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

Kevin Hilman khilman at kernel.org
Fri Mar 20 17:09:30 PDT 2015

"Rafael J. Wysocki" <rjw at rjwysocki.net> writes:

> 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).

Reviewed-by: Kevin Hilman <khilman at linaro.org>

Unless I'm missing somthing, this along with the just the genpd part of
Russell's patch should then fix his problem as well.


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