On Tue, Apr 11, 2017 at 05:54:07PM +0100, Chris Wilson wrote:
> On Tue, Apr 11, 2017 at 07:12:35PM +0300, Imre Deak wrote:
> > +static int i915_pm_prepare(struct device *kdev)
> > +{
> > + /*
> > + * Get a reference to disable the direct complete optimization. This
> > + * is needed, since we have a suspend sequence specific to system
> > + * suspend (that is different from runtime suspend) and because we
> > + * need to provide power to the sound driver while its system suspend
> > + * handler is running. This is not possible with the optimization in
> > + * effect, when the i915 runtime PM is disabled for the whole duration
> > + * of the suspend sequence if the device was already runtime
> > + * suspended at the beginning of the sequence. In this case the i915
> > + * suspend/resume hooks would be also skipped (besides its prepare and
> > + * complete hooks).
> > + */
> > + intel_runtime_pm_get(kdev_to_i915(kdev));
> > +
> > + return 0;
> > +}
> > +
> > +static void i915_pm_complete(struct device *kdev)
> > +{
> > + /* Put the ref taken in the prepare step. */
> > + intel_runtime_pm_put(kdev_to_i915(kdev));
>
> Do we always call i915_pm_complete() if any of the post-prepare suspend
> steps fail? Otherwise, it looks very sensible from our pov.
Yes, it's called even in the failure case (for S3 for example
suspend_devices_and_enter()->Recover_platform:->Resume_devices:->
dpm_resume_end()->dpm_complete()).
--Imre