Input: gameport - let device core tell us if device was registered

No need to keep track of it by ourselves.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/gameport/gameport.c

@@ -561,8 +561,6 @@ static void gameport_add_port(struct gameport *gameport)
 		printk(KERN_ERR
 			"gameport: device_add() failed for %s (%s), error: %d\n",
 			gameport->phys, gameport->name, error);
-	else
-		gameport->registered = 1;
 }
 
 /*
@@ -584,10 +582,8 @@ static void gameport_destroy_port(struct gameport *gameport)
 		gameport->parent = NULL;
 	}
 
-	if (gameport->registered) {
+	if (device_is_registered(&gameport->dev))
 		device_del(&gameport->dev);
-		gameport->registered = 0;
-	}
 
 	list_del_init(&gameport->node);
 

include/linux/gameport.h

@@ -46,7 +46,6 @@ struct gameport {
 	struct mutex drv_mutex;		/* protects serio->drv so attributes can pin driver */
 
 	struct device dev;
-	unsigned int registered;	/* port has been fully registered with driver core */
 
 	struct list_head node;
 };