RE: Does a USB mouse wake a system up from S3?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, 4 Apr 2012, Chen Peter-B29397 wrote:

> > 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.

> 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.

> 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


[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux