[+lkml]
On Thu, Oct 12, 2017 at 5:13 PM, Rajat Jain <raja...@google.com> wrote: > Hi, > > I'm trying to understand when a driver is supposed to call the > pm_wakeup_event(). It appears that the purpose of this call is to > > (1) In the suspend patch, halt the suspend if the driver believes it > just got an appropriate wake event from the device while the system is > trying to suspend. > > (2) If driver detects the event in the resume path, identify the > device as (one of the) wake sources that fired. > > I understand good use cases of this call will be when a driver knows > that its device has woken up the system, e.g: > > * When a driver handles dedicated "wakeup irq", and sees the interrupt fired. > * If a driver detect operator events such as lid opened, power button > pressed, switched to tablet mode etc etc. > > But what should a driver do, when it handles an event (in the resume > path) that potentially was a wake up source but the driver is not > sure? Is it appropriate to call > > if (device_may_wakeup(dev)) > pm_wakeup_event(dev, 0); > > in that case, because I do see some drivers seem to call it when they > think that their device *may* have been the reason the system woke up, > but not necessarily *is* the reason for wake up. E.g.: > > drivers/input/mouse/cyapa.c: > drivers/input/serio/hyperv-keyboard.c > drivers/input/serio/olpc_apsp.c > > Thanks, > > Rajat
