The HID standard defines usages that allow digitizers to report the pen's
height, tilt, and rotation and which are used by Wacom's new "MobileStudio
Pro" devices.

Note that 'hidinput_calc_abs_res' expects ABS_Z (historically used by our
driver to report twist) to have linear units. To ensure it calculates a
resolution with the actually-angular units provided in the HID descriptor
we nedd to lie and tell it we're calculating it for the (rotational) ABS_RZ
axis instead.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>