From: Akinobu Mita <akinobu.mita@gmail.com>

This patch adds a flag to serio driver indicating whether registration is
complete and check that flag in serio_unregister_driver.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 drivers/input/serio/serio.c |    7 ++++++-
 include/linux/serio.h       |    1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff -puN drivers/input/serio/serio.c~input-check-whether-serio-dirver-registration-is-completed drivers/input/serio/serio.c
--- a/drivers/input/serio/serio.c~input-check-whether-serio-dirver-registration-is-completed
+++ a/drivers/input/serio/serio.c
@@ -797,6 +797,8 @@ static void serio_add_driver(struct seri
 		printk(KERN_ERR
 			"serio: driver_register() failed for %s, error: %d\n",
 			drv->driver.name, error);
+	else
+		drv->registered = 1;
 }
 
 int __serio_register_driver(struct serio_driver *drv, struct module *owner)
@@ -823,7 +825,10 @@ start_over:
 		}
 	}
 
-	driver_unregister(&drv->driver);
+	if (drv->registered) {
+		driver_unregister(&drv->driver);
+		drv->registered = 0;
+	}
 	mutex_unlock(&serio_mutex);
 }
 
diff -puN include/linux/serio.h~input-check-whether-serio-dirver-registration-is-completed include/linux/serio.h
--- a/include/linux/serio.h~input-check-whether-serio-dirver-registration-is-completed
+++ a/include/linux/serio.h
@@ -68,6 +68,7 @@ struct serio_driver {
 	void (*cleanup)(struct serio *);
 
 	struct device_driver driver;
+	int registered;
 };
 #define to_serio_driver(d)	container_of(d, struct serio_driver, driver)
 
_