HID: logitech-hidpp: add HID++ 2.0 reprogrammable button support

Some Logitech HID++ 2.0 mice can report diverted reprogrammable controls
through HID++ feature 0x1b04, SpecialKeysMseButtons / REPROG_CONTROLS_V4,
instead of the normal HID mouse report.

Add a quirk-gated event path for those controls. The handler temporarily
diverts verified per-product controls, parses divertedButtonsEvent as the
current pressed-control list, and reports the corresponding evdev key state
for every mapped control.

Keep the control mappings in per-product arrays so adding support for
another mouse does not change the evdev capabilities advertised by
already-supported devices.

Documentation for feature 0x1b04 describes divertedButtonsEvent as a list
of currently pressed diverted buttons, which is the event format handled
here.

Link: https://lekensteyn.nl/files/logitech/x1b04_specialkeysmsebuttons.html
Signed-off-by: Elliot Douglas <edouglas7358@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
This commit is contained in:
Elliot Douglas 2026-07-04 16:10:34 -07:00 • committed by Jiri Kosina
commit 5e21032ac9