Re: [PATCH v2] PM / Domains: Call driver's noirq callbacks

[Mikko Perttunen]

On 20.06.2017 17:18, Ulf Hansson wrote:
> On 20 June 2017 at 15:38, Mikko Perttunen <mperttunen@xxxxxxxxxx> wrote:
> > Currently genpd installs its own suspend_noirq, resume_noirq,
> > and poweroff_noirq callbacks, but never calls down to the driver's
> > corresponding callbacks. Add these calls.
> >
> > Signed-off-by: Mikko Perttunen <mperttunen@xxxxxxxxxx>
> > ---
> > v2:
> > - Moved pm_generic_suspend_noirq to before pm_runtime_force_suspend,
> >   and correspondingly pm_generic_resume_noirq after
> >   pm_runtime_force_resume
> > - Added new pm_genpd_poweroff_noirq callback that is identical to
> >   pm_genpd_suspend_noirq but calls the appropriate driver callback
> >
> >  drivers/base/power/domain.c | 50 ++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 49 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
> > index d3f1d96f75e9..b070ee58186d 100644
> > --- a/drivers/base/power/domain.c
> > +++ b/drivers/base/power/domain.c
> > @@ -919,6 +919,10 @@ static int pm_genpd_suspend_noirq(struct device *dev)
> >         if (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev))
> >                 return 0;
> >
> > +       ret = pm_generic_suspend_noirq(dev);
> > +       if (ret)
> > +               return ret;
> > +
> >         if (genpd->dev_ops.stop && genpd->dev_ops.start) {
> >                 ret = pm_runtime_force_suspend(dev);
> >                 if (ret)
> > @@ -961,6 +965,10 @@ static int pm_genpd_resume_noirq(struct device *dev)
> >         if (genpd->dev_ops.stop && genpd->dev_ops.start)
> >                 ret = pm_runtime_force_resume(dev);
> >
> > +       ret = pm_generic_resume_noirq(dev);
> > +       if (ret)
> > +               return ret;
> > +
> >         return ret;
> >  }
> >
> > @@ -1015,6 +1023,46 @@ static int pm_genpd_thaw_noirq(struct device *dev)
> >  }
> >
> >  /**
> > + * pm_genpd_poweroff_noirq - Completion of hibernation of device in an
> > + *   I/O PM domain.
> > + * @dev: Device to poweroff.
> > + *
> > + * Stop the device and remove power from the domain if all devices in it have
> > + * been stopped.
> > + */
> > +static int pm_genpd_poweroff_noirq(struct device *dev)
> > +{
> > +       struct generic_pm_domain *genpd;
> > +       int ret;
> > +
> > +       dev_dbg(dev, "%s()\n", __func__);
> > +
> > +       genpd = dev_to_genpd(dev);
> > +       if (IS_ERR(genpd))
> > +               return -EINVAL;
> > +
> > +       if (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev))
> > +               return 0;
> > +
> > +       ret = pm_generic_poweroff_noirq(dev);
>
> The only difference between  pm_genpd_suspend_noirq() and
> pm_genpd_poweroff_noirq() is the above line. Can we re-factor the code
> so we avoid open code here, please.

I wasn't sure if the functions' complexity warranted adding a helper 
function, but sure, I'll refactor this with a helper function.

> > +       if (ret)
> > +               return ret;
> > +
> > +       if (genpd->dev_ops.stop && genpd->dev_ops.start) {
> > +               ret = pm_runtime_force_suspend(dev);
> > +               if (ret)
> > +                       return ret;
> > +       }
> > +
> > +       genpd_lock(genpd);
> > +       genpd->suspended_count++;
> > +       genpd_sync_power_off(genpd, true, 0);
> > +       genpd_unlock(genpd);
> > +
> > +       return 0;
> > +}
> > +
> > +/**
> >   * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
> >   * @dev: Device to resume.
> >   *
> > @@ -1493,7 +1541,7 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
> >         genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
> >         genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
> >         genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
> > -       genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
> > +       genpd->domain.ops.poweroff_noirq = pm_genpd_poweroff_noirq;
> >         genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
>
> The pm_genpd_restore_noirq() doesn't invokes the lower level
> ->restore_noirq() callbacks. If you are going to change that for the
> *poweroff* callback, certainly we should change that also for the
> *restore* callbacks as well. Don't you think?
>
> Moreover, what about the freeze and thaw callbacks, should these also
> walk the lower level callbacks?

Yes, I'll add the calls to the rest of the ops as well.

Thanks,
Mikko.

> >         genpd->domain.ops.complete = pm_genpd_complete;
> >
> > --
> > 2.1.4
>
> Kind regards
> Uffe