hwmon: (adt7x10) Add device managed action for restoring config

To simplify the core driver remove function.

Signed-off-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Link: https://lore.kernel.org/r/20211221215841.2641417-3-demonsingur@gmail.com
[groeck: Adjust to use regmap; only register restore function if needed]
Tested-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Reviewed-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/adt7x10.c

@@ -296,6 +296,13 @@ static const struct attribute_group adt7x10_group = {
 	.attrs = adt7x10_attributes,
 };
 
+static void adt7x10_restore_config(void *private)
+{
+	struct adt7x10_data *data = private;
+
+	regmap_write(data->regmap, ADT7X10_CONFIG, data->oldconfig);
+}
+
 int adt7x10_probe(struct device *dev, const char *name, int irq,
 		  struct regmap *regmap)
 {
@@ -333,13 +340,16 @@ int adt7x10_probe(struct device *dev, const char *name, int irq,
 		ret = regmap_write(regmap, ADT7X10_CONFIG, data->config);
 		if (ret)
 			return ret;
+		ret = devm_add_action_or_reset(dev, adt7x10_restore_config, data);
+		if (ret)
+			return ret;
 	}
 	dev_dbg(dev, "Config %02x\n", data->config);
 
 	/* Register sysfs hooks */
 	ret = sysfs_create_group(&dev->kobj, &adt7x10_group);
 	if (ret)
-		goto exit_restore;
+		return ret;
 
 	/*
 	 * The I2C device will already have it's own 'name' attribute, but for
@@ -375,8 +385,6 @@ exit_remove_name:
 		device_remove_file(dev, &dev_attr_name);
 exit_remove:
 	sysfs_remove_group(&dev->kobj, &adt7x10_group);
-exit_restore:
-	regmap_write(regmap, ADT7X10_CONFIG, data->oldconfig);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(adt7x10_probe);
@@ -392,8 +400,6 @@ void adt7x10_remove(struct device *dev, int irq)
 	if (data->name)
 		device_remove_file(dev, &dev_attr_name);
 	sysfs_remove_group(&dev->kobj, &adt7x10_group);
-	if (data->oldconfig != data->config)
-		regmap_write(data->regmap, ADT7X10_CONFIG, data->oldconfig);
 }
 EXPORT_SYMBOL_GPL(adt7x10_remove);