On 29 June 2016 at 02:53, Rafael J. Wysocki <r...@rjwysocki.net> wrote: > From: Rafael J. Wysocki <rafael.j.wyso...@intel.com> > > Arjan reports that it takes a relatively long time to enable runtime > PM for multiple devices at system startup, because all writes to the > "control" attribute in sysfs are handled synchronously and if the > device is suspended as a result of the write, it will block until > that operation is complete. > > That may be avoided by passing the RPM_ASYNC flag to rpm_idle() > in pm_runtime_allow() which will make it execute the device's > "idle" callback asynchronously, so writes to "control" changing > it from "on" to "auto" will return without waiting. > > Reported-by: Arjan van de Ven <ar...@linux.intel.com> > Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com>
Reviewed-by: Ulf Hansson <ulf.hans...@linaro.org> Kind regards Uffe > --- > drivers/base/power/runtime.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: linux-pm/drivers/base/power/runtime.c > =================================================================== > --- linux-pm.orig/drivers/base/power/runtime.c > +++ linux-pm/drivers/base/power/runtime.c > @@ -1256,7 +1256,7 @@ void pm_runtime_allow(struct device *dev > > dev->power.runtime_auto = true; > if (atomic_dec_and_test(&dev->power.usage_count)) > - rpm_idle(dev, RPM_AUTO); > + rpm_idle(dev, RPM_AUTO | RPM_ASYNC); > > out: > spin_unlock_irq(&dev->power.lock); >
