[systemd-devel] [PATCH 0/5] udev/hwdb: Add support for setting trackpoint properties

[Hans de Goede]

Hi All,

Testing has shown that the default experience of trackpoints on different
model laptops differs quite a lot, from almost unusably fast, to just plain
unusably slow on some models.

It seems that before libinput people where using the huge amount of
configurability Xorg gives them to work around this, this is not a
situation which we want to replicate with libinput. Instead the plan is
to where necessary add hwdb entries telling libinput apply a constant
(linear) acceleration factor to deltas from the trackpoint to normalize
the deltas.

This patch-set also adds some special handling for IBM/Lenovo trackpoints which
also have a sysfs driver setting which allows tweaking the sensitivity and on
some models we need to set a specific value to get the best user experience.

This patch-set has been tested (together with a matching libinput patch) on
5 different models sofar: Thinkpad X200s, Thinkpad T440s, Dell Latitude D620,
Dell Latitude E6400, Dell Latitude E6430.

Note the 2 ThinkPad models where specifically chosen as they are known to
have a bad ootb trackpoint experience, so unsurprisingly both end up with
hwdb entries, see:

https://bugzilla.redhat.com/show_bug.cgi?id=1200717
https://forums.lenovo.com/t5/X-Series-ThinkPad-Laptops/Trackpoint-quot-too-slow-quot-proglem-of-X1-Carbon-Gen-2/td-p/1603962

Regards,

Hans