> > > > Have you opened the mouse by apps (like evtest)?, for USB mouse, > > the usbhid->intf->needs_remote_wakeup is only set at .open/.close > > API. That means if you have not opened mouse, the runtime pm status > > for mouse will changed to RPM_ACTIVE (choose_wakeup -> > pm_runtime_resume) > > If you have opened the mouse, the runtime pm status is RPM_SUSPENDED. > > Ah, okay, I will try that. > > > > That's right. The PM core should realize that the usbhid interface > > > is resumed, so it shouldn't try to suspend the root hub. > > > > You mean runtime pm core? I find the runtime pm core doesn't know > > the device has already resumed by system resume. For this case, > > the pm_runtime_set_active(dev) has returned -EBUSY at usb_resume, > > (I am still checking why, should be related to parent- > >power.disable_depth), > > so the usbhid is still RPM_SUSPENDED. > > It sounds like this is the real problem. Under normal conditions, the > runtime PM core won't allow pm_runtime_set_active() to succeed if the > device's parent is suspended. > > In your case, the parent was the root hub, right? So the root hub goes > back into autosuspend too quickly. > > > > The runtime PM status should be correct -- it should indicate that > the > > > device is active after a system resume. > > > > Then, who should take the responsibility to put the device to > autosuspend > > if the device has auto-suspended before the system suspend, we can > > see the ../power/control is still "auto". > > This happens automatically, when the PM core calls pm_runtime_put() > from device_complete() in drivers/base/power/main.c. This has changed > since 3.5 -- in fact, that's probably the explanation for your problem. > Back in 3.5, the pm_runtime_put() call was in device_resume() rather > than device_complete(). It was moved in 3.7. > It works after cherry-pick yours [1] and Ulf Hansson's patch [2] (only your patch should also work), besides, it needs to set controller active after system resume, or the child (roothub) can't set itself as active. ( [1]PM: Prevent runtime suspend during system resume [2] PM / Runtime: Asyncronous idle|suspend devices at system resume) Thanks, Peter -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
