hwmon: (amc6821) Convert to devm_hwmon_device_register_with_groups

Use ATTRIBUTE_GROUPS macro and devm_hwmon_device_register_with_groups() to
simplify the code a bit.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/amc6821.c b/drivers/hwmon/amc6821.c
index 29c17fc..12e851a 100644
--- a/drivers/hwmon/amc6821.c
+++ b/drivers/hwmon/amc6821.c
@@ -152,7 +152,7 @@
  */
 
 struct amc6821_data {
-	struct device *hwmon_dev;
+	struct i2c_client *client;
 	struct mutex update_lock;
 	char valid; /* zero until following fields are valid */
 	unsigned long last_updated; /* in jiffies */
@@ -176,8 +176,8 @@
 
 static struct amc6821_data *amc6821_update_device(struct device *dev)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct amc6821_data *data = i2c_get_clientdata(client);
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
 	int timeout = HZ;
 	u8 reg;
 	int i;
@@ -294,8 +294,8 @@
 		const char *buf,
 		size_t count)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct amc6821_data *data = i2c_get_clientdata(client);
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
 	int ix = to_sensor_dev_attr(attr)->index;
 	long val;
 
@@ -379,8 +379,8 @@
 		const char *buf,
 		size_t count)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct amc6821_data *data = i2c_get_clientdata(client);
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
 	long val;
 	int ret = kstrtol(buf, 10, &val);
 	if (ret)
@@ -408,8 +408,8 @@
 		const char *buf,
 		size_t count)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct amc6821_data *data = i2c_get_clientdata(client);
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
 	long val;
 	int config = kstrtol(buf, 10, &val);
 	if (config)
@@ -519,8 +519,8 @@
 		const char *buf,
 		size_t count)
 {
-	struct i2c_client *client = to_i2c_client(dev);
 	struct amc6821_data *data = amc6821_update_device(dev);
+	struct i2c_client *client = data->client;
 	int ix = to_sensor_dev_attr_2(attr)->index;
 	int nr = to_sensor_dev_attr_2(attr)->nr;
 	u8 *ptemp;
@@ -592,8 +592,8 @@
 		const char *buf,
 		size_t count)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct amc6821_data *data = i2c_get_clientdata(client);
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
 	int dpwm;
 	long val;
 	int ret = kstrtol(buf, 10, &val);
@@ -655,8 +655,8 @@
 		struct device_attribute *attr,
 		const char *buf, size_t count)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct amc6821_data *data = i2c_get_clientdata(client);
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
 	long val;
 	int ix = to_sensor_dev_attr(attr)->index;
 	int ret = kstrtol(buf, 10, &val);
@@ -696,8 +696,8 @@
 		struct device_attribute *attr,
 		const char *buf, size_t count)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct amc6821_data *data = i2c_get_clientdata(client);
+	struct amc6821_data *data = dev_get_drvdata(dev);
+	struct i2c_client *client = data->client;
 	long val;
 	int config = kstrtol(buf, 10, &val);
 	if (config)
@@ -834,9 +834,7 @@
 	NULL
 };
 
-static struct attribute_group amc6821_attr_grp = {
-	.attrs = amc6821_attrs,
-};
+ATTRIBUTE_GROUPS(amc6821);
 
 /* Return 0 if detection is successful, -ENODEV otherwise */
 static int amc6821_detect(
@@ -973,15 +971,16 @@
 static int amc6821_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
+	struct device *dev = &client->dev;
 	struct amc6821_data *data;
+	struct device *hwmon_dev;
 	int err;
 
-	data = devm_kzalloc(&client->dev, sizeof(struct amc6821_data),
-			    GFP_KERNEL);
+	data = devm_kzalloc(dev, sizeof(struct amc6821_data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;
 
-	i2c_set_clientdata(client, data);
+	data->client = client;
 	mutex_init(&data->update_lock);
 
 	/*
@@ -991,28 +990,10 @@
 	if (err)
 		return err;
 
-	err = sysfs_create_group(&client->dev.kobj, &amc6821_attr_grp);
-	if (err)
-		return err;
-
-	data->hwmon_dev = hwmon_device_register(&client->dev);
-	if (!IS_ERR(data->hwmon_dev))
-		return 0;
-
-	err = PTR_ERR(data->hwmon_dev);
-	dev_err(&client->dev, "error registering hwmon device.\n");
-	sysfs_remove_group(&client->dev.kobj, &amc6821_attr_grp);
-	return err;
-}
-
-static int amc6821_remove(struct i2c_client *client)
-{
-	struct amc6821_data *data = i2c_get_clientdata(client);
-
-	hwmon_device_unregister(data->hwmon_dev);
-	sysfs_remove_group(&client->dev.kobj, &amc6821_attr_grp);
-
-	return 0;
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+							   data,
+							   amc6821_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
 static const struct i2c_device_id amc6821_id[] = {
@@ -1028,7 +1009,6 @@
 		.name	= "amc6821",
 	},
 	.probe = amc6821_probe,
-	.remove = amc6821_remove,
 	.id_table = amc6821_id,
 	.detect = amc6821_detect,
 	.address_list = normal_i2c,