[PATCH] i2c: make better use of IDR in i2c-core

This patch uses the already existing IDR mechanism to simplify and
improve the i2c_get_adapter function in i2c-core.

Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/i2c/i2c-core.c

@@ -156,7 +156,7 @@ int i2c_add_adapter(struct i2c_adapter *adap)
 		goto out_unlock;
 	}
 
-	res = idr_get_new(&i2c_adapter_idr, NULL, &id);
+	res = idr_get_new(&i2c_adapter_idr, adap, &id);
 	if (res < 0) {
 		if (res == -EAGAIN)
 			res = -ENOMEM;
@@ -765,20 +765,15 @@ int i2c_adapter_id(struct i2c_adapter *adap)
 
 struct i2c_adapter* i2c_get_adapter(int id)
 {
-	struct list_head   *item;
 	struct i2c_adapter *adapter;
 
 	down(&core_lists);
-	list_for_each(item,&adapters) {
-		adapter = list_entry(item, struct i2c_adapter, list);
-		if (id == adapter->nr &&
-		    try_module_get(adapter->owner)) {
-			up(&core_lists);
-			return adapter;
-		}
-	}
+	adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id);
+	if (adapter && !try_module_get(adapter->owner))
+		adapter = NULL;
+
 	up(&core_lists);
-	return NULL;
+	return adapter;
 }
 
 void i2c_put_adapter(struct i2c_adapter *adap)