Package: linux-image-3.16.0-4-amd64
Version: 3.16.7-ckt11-1
After installing updates today and rebooting, I found that my USB keyboard and mouse, after being idle for exactly two seconds, would be suspended, such that they would not wake up until after a key/button press, and the wake-up press would itself not be reported to software. For the keyboard, this has the effect that the first keystroke or two after being idle would be dropped. For the mouse, the effect is that after being idle, the mouse could no longer move, because movement events would not "wake" it; instead, clicking a button was necessary, after which the mouse would wake up and move normally.
Disabling USB autosuspend fixes the problem. That is:
echo -1 > /sys/module/usbcore/parameters/autosuspend
Then unplug/replug the USB hub to which both devices are attached.
Before disabling as above, the autosuspend value was 2 (presumably meaning 2 seconds?). I verified that setting it back to 2 (and unplugging/re-plugging the devices again) caused the problem to return.
The affected system is a self-assembled desktop with keyboard and mouse connected through a generic USB hub to USB 2.x ports. Please let me know what specific information would be useful for debugging.
-Kenton