i2c: Make i2c_del_driver a void function

Make i2c_del_driver a void function, like all other driver removal
functions. It always returned 0 even when errors occured, and nobody
ever actually checked the return value anyway. And we cannot fail
a module removal anyway.

Signed-off-by: Jean Delvare <[e-mail]>

Documentation/i2c/writing-clients

···
   void foo_cleanup(void)
   {
     if (foo_initialized == 1) {
-      if ((res = i2c_del_driver(&foo_driver))) {
-        printk("foo: Driver registration failed, module not removed.\n");
-        return;
-      }
+      i2c_del_driver(&foo_driver);
       foo_initialized --;
     }
   }

drivers/i2c/i2c-core.c

···
  * i2c_del_driver - unregister I2C driver
  * @driver: the driver being unregistered
  */
-int i2c_del_driver(struct i2c_driver *driver)
+void i2c_del_driver(struct i2c_driver *driver)
 {
 	struct list_head   *item1, *item2, *_n;
 	struct i2c_client  *client;
 	struct i2c_adapter *adap;
-
-	int res = 0;
 
 	mutex_lock(&core_lists);
 
···
 	list_for_each(item1,&adapters) {
 		adap = list_entry(item1, struct i2c_adapter, list);
 		if (driver->detach_adapter) {
-			if ((res = driver->detach_adapter(adap))) {
+			if (driver->detach_adapter(adap)) {
 				dev_err(&adap->dev, "detach_adapter failed "
 					"for driver [%s]\n",
 					driver->driver.name);
-				goto out_unlock;
 			}
 		} else {
 			list_for_each_safe(item2, _n, &adap->clients) {
···
 				dev_dbg(&adap->dev, "detaching client [%s] "
 					"at 0x%02x\n", client->name,
 					client->addr);
-				if ((res = driver->detach_client(client))) {
+				if (driver->detach_client(client)) {
 					dev_err(&adap->dev, "detach_client "
 						"failed for client [%s] at "
 						"0x%02x\n", client->name,
 						client->addr);
-					goto out_unlock;
 				}
 			}
 		}
···
 	list_del(&driver->list);
 	pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name);
 
- out_unlock:
 	mutex_unlock(&core_lists);
-	return 0;
 }
 EXPORT_SYMBOL(i2c_del_driver);
 

drivers/macintosh/therm_windtunnel.c

···
 static int
 therm_of_remove( struct of_device *dev )
 {
-	return i2c_del_driver( &g4fan_driver );
+	i2c_del_driver( &g4fan_driver );
+	return 0;
 }
 
 static struct of_device_id therm_of_match[] = {{

include/linux/i2c.h

···
 extern int i2c_add_numbered_adapter(struct i2c_adapter *);
 
 extern int i2c_register_driver(struct module *, struct i2c_driver *);
-extern int i2c_del_driver(struct i2c_driver *);
+extern void i2c_del_driver(struct i2c_driver *);
 
 static inline int i2c_add_driver(struct i2c_driver *driver)
 {