[PATCH libinput] touchpad: only pair internal trackpoint devices with internal touchpads

[Peter Hutterer]

Internal touchpads with trackpoints are either BUS_I8042 or BUS_I2C, but not
BUS_USB. Lenovo sells external keyboards with a trackpoint built-in, make sure
we don't pair that trackpoint with the internal touchpad.
And likewise, the internal trackpoint should not be paired with e.g. a wacom
touch device.

Lenovo had one external device that has a trackpoint and a touchpad on an
external keyboard. That device won't be covered with this patch, if we have a
user we can re-consider.

https://bugs.freedesktop.org/show_bug.cgi?id=89935

Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
Andreas: sorry about the duplicate, the first one never hit the list for
some reason.

 src/evdev-mt-touchpad.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
index a663db9..aa59869 100644
--- a/src/evdev-mt-touchpad.c
+++ b/src/evdev-mt-touchpad.c
@@ -825,9 +825,16 @@ tp_device_added(struct evdev_device *device,
 		struct evdev_device *added_device)
 {
 	struct tp_dispatch *tp = (struct tp_dispatch*)device->dispatch;
+	unsigned int bus_tp = libevdev_get_id_bustype(device->evdev),
+		     bus_trp = libevdev_get_id_bustype(added_device->evdev);
+	bool tp_is_internal, trp_is_internal;
+
+	tp_is_internal = bus_tp != BUS_USB && bus_tp != BUS_BLUETOOTH;
+	trp_is_internal = bus_trp != BUS_USB && bus_trp != BUS_BLUETOOTH;
 
 	if (tp->buttons.trackpoint == NULL &&
-	    (added_device->tags & EVDEV_TAG_TRACKPOINT)) {
+	    (added_device->tags & EVDEV_TAG_TRACKPOINT) &&
+	    tp_is_internal && trp_is_internal) {
 		/* Don't send any pending releases to the new trackpoint */
 		tp->buttons.active_is_topbutton = false;
 		tp->buttons.trackpoint = added_device;
-- 
2.3.4