hwmon: (adt7470) Convert to a new-style i2c driver

The new-style adt7470 driver implements the optional detect() callback
to cover the use cases of the legacy driver.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Darrick J. Wong <djwong@us.ibm.com>

drivers/hwmon/adt7470.c

@@ -138,7 +138,6 @@ I2C_CLIENT_INSMOD_1(adt7470);
 #define FAN_DATA_VALID(x)	((x) && (x) != FAN_PERIOD_INVALID)
 
 struct adt7470_data {
-	struct i2c_client	client;
 	struct device		*hwmon_dev;
 	struct attribute_group	attrs;
 	struct mutex		lock;
@@ -164,16 +163,28 @@ struct adt7470_data {
 	u8			pwm_auto_temp[ADT7470_PWM_COUNT];
 };
 
-static int adt7470_attach_adapter(struct i2c_adapter *adapter);
-static int adt7470_detect(struct i2c_adapter *adapter, int address, int kind);
-static int adt7470_detach_client(struct i2c_client *client);
+static int adt7470_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id);
+static int adt7470_detect(struct i2c_client *client, int kind,
+			  struct i2c_board_info *info);
+static int adt7470_remove(struct i2c_client *client);
+
+static const struct i2c_device_id adt7470_id[] = {
+	{ "adt7470", adt7470 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, adt7470_id);
 
 static struct i2c_driver adt7470_driver = {
+	.class		= I2C_CLASS_HWMON,
 	.driver = {
 		.name	= "adt7470",
 	},
-	.attach_adapter	= adt7470_attach_adapter,
-	.detach_client	= adt7470_detach_client,
+	.probe		= adt7470_probe,
+	.remove		= adt7470_remove,
+	.id_table	= adt7470_id,
+	.detect		= adt7470_detect,
+	.address_data	= &addr_data,
 };
 
 /*
@@ -1004,64 +1015,52 @@ static struct attribute *adt7470_attr[] =
 	NULL
 };
 
-static int adt7470_attach_adapter(struct i2c_adapter *adapter)
-{
-	if (!(adapter->class & I2C_CLASS_HWMON))
-		return 0;
-	return i2c_probe(adapter, &addr_data, adt7470_detect);
-}
-
-static int adt7470_detect(struct i2c_adapter *adapter, int address, int kind)
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int adt7470_detect(struct i2c_client *client, int kind,
+			  struct i2c_board_info *info)
 {
-	struct i2c_client *client;
-	struct adt7470_data *data;
-	int err = 0;
+	struct i2c_adapter *adapter = client->adapter;
 
 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
-		goto exit;
-
-	if (!(data = kzalloc(sizeof(struct adt7470_data), GFP_KERNEL))) {
-		err = -ENOMEM;
-		goto exit;
-	}
-
-	client = &data->client;
-	client->addr = address;
-	client->adapter = adapter;
-	client->driver = &adt7470_driver;
-
-	i2c_set_clientdata(client, data);
-
-	mutex_init(&data->lock);
+		return -ENODEV;
 
 	if (kind <= 0) {
 		int vendor, device, revision;
 
 		vendor = i2c_smbus_read_byte_data(client, ADT7470_REG_VENDOR);
-		if (vendor != ADT7470_VENDOR) {
-			err = -ENODEV;
-			goto exit_free;
-		}
+		if (vendor != ADT7470_VENDOR)
+			return -ENODEV;
 
 		device = i2c_smbus_read_byte_data(client, ADT7470_REG_DEVICE);
-		if (device != ADT7470_DEVICE) {
-			err = -ENODEV;
-			goto exit_free;
-		}
+		if (device != ADT7470_DEVICE)
+			return -ENODEV;
 
 		revision = i2c_smbus_read_byte_data(client,
 						    ADT7470_REG_REVISION);
-		if (revision != ADT7470_REVISION) {
-			err = -ENODEV;
-			goto exit_free;
-		}
+		if (revision != ADT7470_REVISION)
+			return -ENODEV;
 	} else
 		dev_dbg(&adapter->dev, "detection forced\n");
 
-	strlcpy(client->name, "adt7470", I2C_NAME_SIZE);
+	strlcpy(info->type, "adt7470", I2C_NAME_SIZE);
 
-	if ((err = i2c_attach_client(client)))
-		goto exit_free;
+	return 0;
+}
+
+static int adt7470_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct adt7470_data *data;
+	int err;
+
+	data = kzalloc(sizeof(struct adt7470_data), GFP_KERNEL);
+	if (!data) {
+		err = -ENOMEM;
+		goto exit;
+	}
+
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->lock);
 
 	dev_info(&client->dev, "%s chip found\n", client->name);
 
@@ -1071,7 +1070,7 @@ static int adt7470_detect(struct i2c_adapter *adapter, int address, int kind)
 	/* Register sysfs hooks */
 	data->attrs.attrs = adt7470_attr;
 	if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs)))
-		goto exit_detach;
+		goto exit_free;
 
 	data->hwmon_dev = hwmon_device_register(&client->dev);
 	if (IS_ERR(data->hwmon_dev)) {
@@ -1083,21 +1082,18 @@ static int adt7470_detect(struct i2c_adapter *adapter, int address, int kind)
 
 exit_remove:
 	sysfs_remove_group(&client->dev.kobj, &data->attrs);
-exit_detach:
-	i2c_detach_client(client);
 exit_free:
 	kfree(data);
 exit:
 	return err;
 }
 
-static int adt7470_detach_client(struct i2c_client *client)
+static int adt7470_remove(struct i2c_client *client)
 {
 	struct adt7470_data *data = i2c_get_clientdata(client);
 
 	hwmon_device_unregister(data->hwmon_dev);
 	sysfs_remove_group(&client->dev.kobj, &data->attrs);
-	i2c_detach_client(client);
 	kfree(data);
 	return 0;
 }