evdev: Add a remove callback to the evdev_dispatch_interface

Some dispatchers may want to do some cleanup at remove time, rather then at
destroy time.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

src/evdev-mt-touchpad.c

@@ -858,6 +858,7 @@ tp_tag_device(struct evdev_device *device,
 
 static struct evdev_dispatch_interface tp_interface = {
 	tp_process,
+	NULL, /* remove */
 	tp_destroy,
 	tp_device_added,
 	tp_device_removed,

src/evdev.c

@@ -737,6 +737,7 @@ evdev_calibration_get_default_matrix(struct libinput_device *libinput_device,
 
 struct evdev_dispatch_interface fallback_interface = {
 	fallback_process,
+	NULL, /* remove */
 	fallback_destroy,
 	NULL, /* device_added */
 	NULL, /* device_removed */
@@ -2041,6 +2042,9 @@ evdev_device_remove(struct evdev_device *device)
 
 	evdev_device_suspend(device);
 
+	if (device->dispatch->interface->remove)
+		device->dispatch->interface->remove(device->dispatch);
+
 	/* A device may be removed while suspended, mark it to
 	 * skip re-opening a different device with the same node */
 	device->was_removed = true;

src/evdev.h

@@ -166,6 +166,9 @@ struct evdev_dispatch_interface {
 			struct input_event *event,
 			uint64_t time);
 
+	/* Device is being removed (may be NULL) */
+	void (*remove)(struct evdev_dispatch *dispatch);
+
 	/* Destroy an event dispatch handler and free all its resources. */
 	void (*destroy)(struct evdev_dispatch *dispatch);