Change a bit the finger detection method used by the appletouch
driver to reduce touchpad "jumpiness":
- Adjust the method for detecting multiple fingers. Previously, it
recognized a new finger when a low sensor reading is followed by
a high sensor reading. The new method checks for 'humps' in the
sensor readings, so there doesn't necessarily have to be a low
sensor between two high sensors for two fingers to be triggered.
This allows detecting presence of two fingers on the touchpad
even when they touch each other.
- Change absolute coordinate calculation to us to get rid of "jumps".
Instead of using full value from a sensor once it passes the
threshold subtract theshold value from the reading.
- Allow adjusting threshold value via module parameter.
The patch doesn't seem to affect the Powerbooks but does greatly improve
the touchpad behaviour on the MacBooks.
Signed-off-by: Jason Parekh <jasonparekh@gmail.com>
Signed-off-by: Stelian Pop <stelian@popies.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
00081d3729