hwmon: (tmp401) Use multi-byte regmap operations

Use multi-byte regmap operations where possible to reduce code size
and the need for mutex protection.

No functional change.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/tmp401.c

@@ -308,7 +308,9 @@ static int tmp401_temp_read(struct device *dev, u32 attr, int channel, long *val
 {
 	struct tmp401_data *data = dev_get_drvdata(dev);
 	struct regmap *regmap = data->regmap;
+	unsigned int regs[2] = { TMP401_TEMP_MSB[3][channel], TMP401_TEMP_CRIT_HYST };
 	unsigned int regval;
+	u16 regvals[2];
 	int reg, ret;
 
 	switch (attr) {
@@ -325,20 +327,11 @@ static int tmp401_temp_read(struct device *dev, u32 attr, int channel, long *val
 		*val = tmp401_register_to_temp(regval, data->extended_range);
 		break;
 	case hwmon_temp_crit_hyst:
-		mutex_lock(&data->update_lock);
-		reg = TMP401_TEMP_MSB[3][channel];
-		ret = regmap_read(regmap, reg, &regval);
-		if (ret < 0)
-			goto unlock;
-		*val = tmp401_register_to_temp(regval, data->extended_range);
-		ret = regmap_read(regmap, TMP401_TEMP_CRIT_HYST, &regval);
-		if (ret < 0)
-			goto unlock;
-		*val -= regval * 1000;
-unlock:
-		mutex_unlock(&data->update_lock);
+		ret = regmap_multi_reg_read(regmap, regs, regvals, 2);
 		if (ret < 0)
 			return ret;
+		*val = tmp401_register_to_temp(regvals[0], data->extended_range) -
+							(regvals[1] * 1000);
 		break;
 	case hwmon_temp_fault:
 	case hwmon_temp_min_alarm: