Input: mac_hid - add lockdep annotation to emumousebtn

The mouse button emulation calls input device methods from an input
device. This causes funny lock nesting which is harmless as each
device has its own locks.

Give the nesting device its own lock classes so that lockdep will not
consider them the same.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/macintosh/mac_hid.c

@@ -103,6 +103,9 @@ int mac_hid_mouse_emulate_buttons(int caller, unsigned int keycode, int down)
 	return 0;
 }
 
+static struct lock_class_key emumousebtn_event_class;
+static struct lock_class_key emumousebtn_mutex_class;
+
 static int emumousebtn_input_register(void)
 {
 	int ret;
@@ -111,6 +114,9 @@ static int emumousebtn_input_register(void)
 	if (!emumousebtn)
 		return -ENOMEM;
 
+	lockdep_set_class(emumousebtn->event_lock, &emumousebtn_event_class);
+	lockdep_set_class(emumousebtn->mutex, &emumousebtn_mutex_class);
+
 	emumousebtn->name = "Macintosh mouse button emulation";
 	emumousebtn->id.bustype = BUS_ADB;
 	emumousebtn->id.vendor = 0x0001;