hwmon: (sht21) 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>

drivers/hwmon/sht21.c

@@ -45,7 +45,7 @@
  * @humidity: cached humidity measurement value
  */
 struct sht21 {
-	struct device *hwmon_dev;
+	struct i2c_client *client;
 	struct mutex lock;
 	char valid;
 	unsigned long last_update;
@@ -85,14 +85,15 @@ static inline int sht21_rh_ticks_to_per_cent_mille(int ticks)
 
 /**
  * sht21_update_measurements() - get updated measurements from device
- * @client: I2C client device
+ * @dev: device
  *
  * Returns 0 on success, else negative errno.
  */
-static int sht21_update_measurements(struct i2c_client *client)
+static int sht21_update_measurements(struct device *dev)
 {
 	int ret = 0;
-	struct sht21 *sht21 = i2c_get_clientdata(client);
+	struct sht21 *sht21 = dev_get_drvdata(dev);
+	struct i2c_client *client = sht21->client;
 
 	mutex_lock(&sht21->lock);
 	/*
@@ -133,9 +134,10 @@ static ssize_t sht21_show_temperature(struct device *dev,
 	struct device_attribute *attr,
 	char *buf)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct sht21 *sht21 = i2c_get_clientdata(client);
-	int ret = sht21_update_measurements(client);
+	struct sht21 *sht21 = dev_get_drvdata(dev);
+	int ret;
+
+	ret = sht21_update_measurements(dev);
 	if (ret < 0)
 		return ret;
 	return sprintf(buf, "%d\n", sht21->temperature);
@@ -154,9 +156,10 @@ static ssize_t sht21_show_humidity(struct device *dev,
 	struct device_attribute *attr,
 	char *buf)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct sht21 *sht21 = i2c_get_clientdata(client);
-	int ret = sht21_update_measurements(client);
+	struct sht21 *sht21 = dev_get_drvdata(dev);
+	int ret;
+
+	ret = sht21_update_measurements(dev);
 	if (ret < 0)
 		return ret;
 	return sprintf(buf, "%d\n", sht21->humidity);
@@ -168,30 +171,20 @@ static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, sht21_show_temperature,
 static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, sht21_show_humidity,
 	NULL, 0);
 
-static struct attribute *sht21_attributes[] = {
+static struct attribute *sht21_attrs[] = {
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
 	&sensor_dev_attr_humidity1_input.dev_attr.attr,
 	NULL
 };
 
-static const struct attribute_group sht21_attr_group = {
-	.attrs = sht21_attributes,
-};
+ATTRIBUTE_GROUPS(sht21);
 
-/**
- * sht21_probe() - probe device
- * @client: I2C client device
- * @id: device ID
- *
- * Called by the I2C core when an entry in the ID table matches a
- * device's name.
- * Returns 0 on success.
- */
 static int sht21_probe(struct i2c_client *client,
 	const struct i2c_device_id *id)
 {
+	struct device *dev = &client->dev;
+	struct device *hwmon_dev;
 	struct sht21 *sht21;
-	int err;
 
 	if (!i2c_check_functionality(client->adapter,
 				     I2C_FUNC_SMBUS_WORD_DATA)) {
@@ -200,47 +193,17 @@ static int sht21_probe(struct i2c_client *client,
 		return -ENODEV;
 	}
 
-	sht21 = devm_kzalloc(&client->dev, sizeof(*sht21), GFP_KERNEL);
+	sht21 = devm_kzalloc(dev, sizeof(*sht21), GFP_KERNEL);
 	if (!sht21)
 		return -ENOMEM;
 
-	i2c_set_clientdata(client, sht21);
+	sht21->client = client;
 
 	mutex_init(&sht21->lock);
 
-	err = sysfs_create_group(&client->dev.kobj, &sht21_attr_group);
-	if (err) {
-		dev_dbg(&client->dev, "could not create sysfs files\n");
-		return err;
-	}
-	sht21->hwmon_dev = hwmon_device_register(&client->dev);
-	if (IS_ERR(sht21->hwmon_dev)) {
-		dev_dbg(&client->dev, "unable to register hwmon device\n");
-		err = PTR_ERR(sht21->hwmon_dev);
-		goto fail_remove_sysfs;
-	}
-
-	dev_info(&client->dev, "initialized\n");
-
-	return 0;
-
-fail_remove_sysfs:
-	sysfs_remove_group(&client->dev.kobj, &sht21_attr_group);
-	return err;
-}
-
-/**
- * sht21_remove() - remove device
- * @client: I2C client device
- */
-static int sht21_remove(struct i2c_client *client)
-{
-	struct sht21 *sht21 = i2c_get_clientdata(client);
-
-	hwmon_device_unregister(sht21->hwmon_dev);
-	sysfs_remove_group(&client->dev.kobj, &sht21_attr_group);
-
-	return 0;
+	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
+							   sht21, sht21_groups);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
 }
 
 /* Device ID table */
@@ -253,7 +216,6 @@ MODULE_DEVICE_TABLE(i2c, sht21_id);
 static struct i2c_driver sht21_driver = {
 	.driver.name = "sht21",
 	.probe       = sht21_probe,
-	.remove      = sht21_remove,
 	.id_table    = sht21_id,
 };