> > > I have some customers asking why a usb mouse doesn't wake a system up > > > from > > > S3 on RHEL-6. I have poked at a 3.3 kernel and noticed the same > > > behaviour. Is this true or do I have something misconfigured? > > > > > > I talked with Matthew Garret about this, he mentioned something like > > > /sys/bus/usb/devices/usb1/power/wakeup would need to enabled for the > > > mouse > > > to work. I tried this with no success. > > > > > > So before I started to investigated, I was wondering what the > > > expectations > > > were for something like this. > > > > > 1. Make sure the VBUS is on at your S3 status, the mouse's LED is > should be on. > > This is questionable. An LED consumes more than the maximum amount of > current that a suspended device is allowed to use. So if the mouse's > LED really is turned on, it means the mouse is not compliant with the > USB specification. IIRC, my USB mouse turns off its LED when it is > suspended. > > On the other hand, if VBUS isn't turned on then the mouse certainly > won't be able to send a wakeup request. > I did a test on my board, Alan is correct, LED will be off during the system suspend. Yes, according to USB spec, the suspended device should not be drawn more than 2.5mA from the host, so LED should be off. > > 2. make sure your mouse is remote wakeup featured. > > 3. Make sure the wakeup is enabled from the roothub to mouse. > > For example, if your mouse is at bus 5(using lsusb to get), and there > is a hub at this > > bus, the mouse is connected one of the ports. > > > > echo enabled > /sys/bus/usb/devices/usb5/power/wakeup (roothub) > > echo enabled > /sys/bus/usb/devices/5-2/power/wakeup (hub) > > This step isn't necessary. Intermediate hubs do not need to be enabled > for wakeup; they will always forward wakeup requests to their upstream > port regardless. > I did a test on my board, Alan is correct. If mouse is set by remote wakeup enabled (through USB_REQ_SET_FEATURE), even the intermediate hub is set by remote wakeup disable (through USB_REQ_CLEAR_FEATURE), the host controller still can be wakeup. But if there is no device at the hub, the system can't be wakeup by device connection event without set enabled to hub/power/wakeup. > > echo enabled > /sys/bus/usb/devices/5-2.1/power/wakeup (mouse) > > 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
