Some devices have worn-out switches or just cheap switches that trigger
multiple button events for each press. These can be identified by unfeasably
short time deltas between the release and the next press event. In the
recordings I've seen so far, that timeout is 8ms.
We have a two-stage behavior: by default, we do not delay any events but we
monitor timestamps. The first time a bouncing button is detected we switch to
debounce mode. From then on, release events are delayed slightly to check for
subsequent button events. If one occurs, the releas and press are filtered. If
none occurs, the release event is passed to the caller.
https://bugs.freedesktop.org/show_bug.cgi?id=100057
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
