Input: joydev - allow binding to button-only devices

Dance pads don't have an axis, so allow this kind of controllers
to be used via legacy joystick interface.
Signed-off-by: NChristoph Fritz <chf.fritz@googlemail.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

drivers/input/joydev.c

@@ -929,6 +929,24 @@ static const struct input_device_id joydev_ids[] = {
 		.evbit = { BIT_MASK(EV_ABS) },
 		.absbit = { BIT_MASK(ABS_THROTTLE) },
 	},
+	{
+		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
+				INPUT_DEVICE_ID_MATCH_KEYBIT,
+		.evbit = { BIT_MASK(EV_KEY) },
+		.keybit = {[BIT_WORD(BTN_JOYSTICK)] = BIT_MASK(BTN_JOYSTICK) },
+	},
+	{
+		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
+				INPUT_DEVICE_ID_MATCH_KEYBIT,
+		.evbit = { BIT_MASK(EV_KEY) },
+		.keybit = { [BIT_WORD(BTN_GAMEPAD)] = BIT_MASK(BTN_GAMEPAD) },
+	},
+	{
+		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
+				INPUT_DEVICE_ID_MATCH_KEYBIT,
+		.evbit = { BIT_MASK(EV_KEY) },
+		.keybit = { [BIT_WORD(BTN_TRIGGER_HAPPY)] = BIT_MASK(BTN_TRIGGER_HAPPY) },
+	},
 	{ }	/* Terminating entry */
 };