The button up debouncing states mirror the button down states with the
addition of the spurious debouncing states. Rename the states to better
show this symmetry.
This enables us to specify the location that needs to be arbitrated, rather
than just disabling the whole device altogether. This patch just adds the
hooks, no implementation.
This is internal API only, one backend can specify an area in mm which gets
converted to device coordinates in the target device and arbitrated there.
Right now, everything simply passes NULL.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
This enables us to change the types of touch arbitration, with the focus on
allowing location-based touch arbitration as well as the more generic "disable
everything".
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
When a hand is resting on a pen+touch device, lifting the hand may remove the
stylus from proximity before the hand leaves the surface. If the kernel
performs touch arbitration, this triggers a touch down on proximity out,
followed by a touch up immediately after when the hand stops touching.
This can cause ghost touch events. Prevent this by using a timer-based
arbitration toggle.
Same as 2a378beab0 but for the fallback
interface.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
This removes the artificial 3 keyboard limit. If you have more internal
keyboards than that, something is wrong in your setup but that shouldn't stop
us from working. Or more specificially: this can happen easily when running
tests so let's not fail the test suite because we created a few hundred
keyboards.
We'll still throw out a log message though.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
This removes the artificial 3 keyboard limit. If you have more internal
keyboards than that, something is wrong in your setup but that shouldn't stop
us from working. Or more specificially: this can happen easily when running
tests so let's not fail the test suite because we created a few hundred
keyboards.
We'll still throw out a log message though.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
A set of wireless devices that can scramble the timestamps, so we get
press/release within 8ms even though I doubt the user is capable of doing
this. Since they're generally good quality anyway, let's just disable
debouncing on those until someone complains and we need something more
sophisticated.
https://bugs.freedesktop.org/show_bug.cgi?id=104415
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
The current debouncing code monitors events and switches on when events are
too close together. From then on, any event can be delayed.
Vicente Bergas provided an algorithm that avoids most of these delays:
on a button state change we now forward the change without delay but start a
timer. If the button changes state during that timer, the changes are
ignored. On timer expiry, events are sent to match the hardware state
with the client's view of the device. This is only done if needed.
Thus, a press-release sequence of: PRP sends a single press event, a sequence of
PRPR sends press and then the release at the end of the timeout. The timeout
is short enough that the delay should not be noticeable.
This new mode is called the 'bounce' mode. The old mode is now referred to as
'spurious' mode and only covers the case of a button held down that loses
contact. It works as before, monitoring a button for these spurious contact
losses and switching on. When on, button release events are delayed as before.
The whole button debouncing moves to a state machine which makes debugging a
lot easier. See the accompanying SVG for the diagram.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
The previous approach was to remember the last event and flush it at the right
time. The new approach is to update the device state during the frame and send
out the events at EV_SYN time.
This gives us two advantages: we are not dependent on the kernel order of how
events come in and we can process events depending on other events in the same
frame. This will come in handy later for button debouncing.
This is also the approach we have in the touchpad and tablet backends.
Two FIXMEs are left in place, the button debouncing code and the lid switch
code. Both need to be handled in future patches.
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
