hwmon: (adt7x10) Rely on subsystem locking

Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.

Signed-off-by: Guenter Roeck <[e-mail]>
Reviewed-by: Nuno Sá <[e-mail]>

drivers/hwmon/adt7x10.c

···
 #include <linux/jiffies.h>
 #include <linux/hwmon.h>
 #include <linux/err.h>
-#include <linux/mutex.h>
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/regmap.h>
···
 /* Each client has this additional data */
 struct adt7x10_data {
 	struct regmap		*regmap;
-	struct mutex		update_lock;
 	u8			config;
 	u8			oldconfig;
 	bool			valid;		/* true if temperature valid */
···
 	unsigned int regval;
 	int ret;
 
-	mutex_lock(&data->update_lock);
 	if (index == adt7x10_temperature && !data->valid) {
 		/* wait for valid temperature */
 		ret = adt7x10_temp_ready(data->regmap);
-		if (ret) {
-			mutex_unlock(&data->update_lock);
+		if (ret)
 			return ret;
-		}
 		data->valid = true;
 	}
-	mutex_unlock(&data->update_lock);
 
 	ret = regmap_read(data->regmap, ADT7X10_REG_TEMP[index], &regval);
 	if (ret)
···
 
 static int adt7x10_temp_write(struct adt7x10_data *data, int index, long temp)
 {
-	int ret;
-
-	mutex_lock(&data->update_lock);
-	ret = regmap_write(data->regmap, ADT7X10_REG_TEMP[index],
-			   ADT7X10_TEMP_TO_REG(temp));
-	mutex_unlock(&data->update_lock);
-	return ret;
+	return regmap_write(data->regmap, ADT7X10_REG_TEMP[index],
+			    ADT7X10_TEMP_TO_REG(temp));
 }
 
 static int adt7x10_hyst_read(struct adt7x10_data *data, int index, long *val)
···
 	unsigned int regval;
 	int limit, ret;
 
-	mutex_lock(&data->update_lock);
-
 	/* convert absolute hysteresis value to a 4 bit delta value */
 	ret = regmap_read(data->regmap, ADT7X10_T_ALARM_HIGH, &regval);
 	if (ret < 0)
-		goto abort;
+		return ret;
 
 	limit = ADT7X10_REG_TO_TEMP(data, regval);
 
 	hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
 	regval = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 0,
 			   ADT7X10_T_HYST_MASK);
-	ret = regmap_write(data->regmap, ADT7X10_T_HYST, regval);
-abort:
-	mutex_unlock(&data->update_lock);
-	return ret;
+	return regmap_write(data->regmap, ADT7X10_T_HYST, regval);
 }
 
 static int adt7x10_alarm_read(struct adt7x10_data *data, int index, long *val)
···
 	data->regmap = regmap;
 
 	dev_set_drvdata(dev, data);
-	mutex_init(&data->update_lock);
 
 	/* configure as specified */
 	ret = regmap_read(regmap, ADT7X10_CONFIG, &config);