i2c: improve error messages in i2c_register_adapter()

Switch to WARN if no adapter name is given, otherwise we won't know who
missed to do that. Add error message if device registration fails.
Update error message for missing algo to match style of the others.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/i2c-core.c

@@ -1604,14 +1604,11 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
 	}
 
 	/* Sanity checks */
-	if (unlikely(adap->name[0] == '\0')) {
-		pr_err("i2c-core: Attempt to register an adapter with "
-		       "no name!\n");
+	if (WARN(!adap->name[0], "i2c adapter has no name"))
 		goto out_list;
-	}
-	if (unlikely(!adap->algo)) {
-		pr_err("i2c-core: Attempt to register adapter '%s' with "
-		       "no algo!\n", adap->name);
+
+	if (!adap->algo) {
+		pr_err("i2c-core: adapter '%s': no algo supplied!\n", adap->name);
 		goto out_list;
 	}
 
@@ -1634,8 +1631,11 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
 	adap->dev.bus = &i2c_bus_type;
 	adap->dev.type = &i2c_adapter_type;
 	res = device_register(&adap->dev);
-	if (res)
+	if (res) {
+		pr_err("i2c-core: adapter '%s': can't register device (%d)\n",
+			adap->name, res);
 		goto out_list;
+	}
 
 	dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name);