Re: [PATCH v3 1/3] PM: runtime: add devm_pm_runtime_enable helper

[Rafael J. Wysocki]

On Wed, Aug 4, 2021 at 11:03 PM Dmitry Baryshkov
<dmitry.baryshkov@xxxxxxxxxx> wrote:
>
> On Wed, 4 Aug 2021 at 21:07, Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> >
> > On Sat, Jul 31, 2021 at 9:50 PM Dmitry Baryshkov
> > <dmitry.baryshkov@xxxxxxxxxx> wrote:
> > >
> > > A typical code pattern for pm_runtime_enable() call is to call it in the
> > > _probe function and to call pm_runtime_disable() both from _probe error
> > > path and from _remove function. For some drivers the whole remove
> > > function would consist of the call to pm_remove_disable().
> > >
> > > Add helper function to replace this bolierplate piece of code. Calling
> > > devm_pm_runtime_enable() removes the need for calling
> > > pm_runtime_disable() both in the probe()'s error path and in the
> > > remove() function.
> > >
> > > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> > > ---
> > >  drivers/base/power/runtime.c | 17 +++++++++++++++++
> > >  include/linux/pm_runtime.h   |  4 ++++
> > >  2 files changed, 21 insertions(+)
> > >
> > > diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
> > > index 8a66eaf731e4..ec94049442b9 100644
> > > --- a/drivers/base/power/runtime.c
> > > +++ b/drivers/base/power/runtime.c
> > > @@ -1447,6 +1447,23 @@ void pm_runtime_enable(struct device *dev)
> > >  }
> > >  EXPORT_SYMBOL_GPL(pm_runtime_enable);
> > >
> > > +static void pm_runtime_disable_action(void *data)
> > > +{
> > > +       pm_runtime_disable(data);
> > > +}
> > > +
> > > +/**
> > > + * devm_pm_runtime_enable - devres-enabled version of pm_runtime_enable.
> > > + * @dev: Device to handle.
> > > + */
> > > +int devm_pm_runtime_enable(struct device *dev)
> > > +{
> > > +       pm_runtime_enable(dev);
> > > +
> > > +       return devm_add_action_or_reset(dev, pm_runtime_disable_action, dev);
> >
> > When exactly is pm_runtime_disable_action() going to run by this rule?
> >  When the device goes away or when the driver is unbound from it?
>
> When the driver is unbound (either because probe() returns an error or
> because __device_release_driver() is being called).
> This corresponds to a typical call to pm_runtime_disable() from the
> probe()'s error path or in the remove() callback.

OK, so

Acked-by: Rafael J. Wysocki <rafael@xxxxxxxxxx>

for the PM-runtime framework changes in this series (patches [1-2/3])
and please feel free to route them in through whatever tree is most
suitable (or let me know if you want me to pick them up).