On Tue, 23 Dec 2014, Du, Changbin wrote: > > You have to make sure that wakeup is also enabled for the host > > controller the device is attached to. For some host controllers, it > > may also be necessary to enable wakeup for the root hub. > > > Yes, the root-hub is not wakeup enabled by default, actually hub > devices are not enabled. It works after I enable it via sysfs interface. On some hardware, device wakeup requests can work even when root-hub wakeup is disabled -- it varies. In general we do not want hubs to be enabled for wakeup. If they were, then your computer would wake up the moment you unplugged a USB device. You would not be able to (for example) to put your laptop to sleep, unplug a USB mouse, and put the laptop in its case. > > > Could we also enable wakeup for usb mouse? Or is there any concern to > > enable it? > > > Per my opinion, most people may expect clicking mouse can awake system. > > > > It doesn't matter to me, but you should ask the people on the > > linux-input mailing list. > > > > Also, what about wakeup for a non-USB mouse? Shouldn't that be enabled > > as well? > Unfortunately the mouse I found are all of usb so cannot confirm it. The > concern is if we want usb keyboard/mouse wakeup work by default, it does > make sense only if the parent hubs are also enabled by default. This is a policy > issue and may be better place it on userspace. I have no better idea :) . As mentioned above, it depends on the hardware. Alan Stern -- 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
