Messages in this thread | | | From | "Rafael J. Wysocki" <> | Date | Fri, 13 Jan 2023 20:54:41 +0100 | Subject | Re: [PATCH] PM: runtime: Document that force_suspend() is incompatible with SMART_SUSPEND |
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On Tue, Dec 13, 2022 at 4:54 PM Richard Fitzgerald <rf@opensource.cirrus.com> wrote: > > pm_runtime_force_suspend() cannot be used with DPM_FLAG_SMART_SUSPEND, so > note this in the kerneldoc. > > If DPM_FLAG_SMART_SUSPEND is set and the PM core cannot skip system resume > it will call pm_runtime_active() on the driver. This can lead to an > inconsistent state where: > > pm_runtime_force_suspend() called ->runtime_suspend > > but > > device_resume_noirq() called pm_runtime_set_active() > > This leaves the driver actually suspended but marked as active. > > Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> > --- > drivers/base/power/runtime.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c > index 50e726b6c2cf..b29be7d4d7d0 100644 > --- a/drivers/base/power/runtime.c > +++ b/drivers/base/power/runtime.c > @@ -1864,6 +1864,10 @@ static bool pm_runtime_need_not_resume(struct device *dev) > * sure the device is put into low power state and it should only be used during > * system-wide PM transitions to sleep states. It assumes that the analogous > * pm_runtime_force_resume() will be used to resume the device. > + * > + * Do not use with DPM_FLAG_SMART_SUSPEND as this can lead to an inconsistent > + * state where this function has called the ->runtime_suspend callback but the > + * PM core marks the driver as runtime active. > */ > int pm_runtime_force_suspend(struct device *dev) > { > --
Applied as 6.3 material, thanks!
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