hwmon: (pmbus) Use long variables for register to data conversions

Using integer variable types for register to data conversions can cause
overflows especially for power calculations, which are in microwatt.
Use long variables instead.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@kernel.org # 2.6.39+
diff --git a/drivers/hwmon/pmbus_core.c b/drivers/hwmon/pmbus_core.c
index 744672c..8e31a8e 100644
--- a/drivers/hwmon/pmbus_core.c
+++ b/drivers/hwmon/pmbus_core.c
@@ -362,8 +362,8 @@
  * Convert linear sensor values to milli- or micro-units
  * depending on sensor type.
  */
-static int pmbus_reg2data_linear(struct pmbus_data *data,
-				 struct pmbus_sensor *sensor)
+static long pmbus_reg2data_linear(struct pmbus_data *data,
+				  struct pmbus_sensor *sensor)
 {
 	s16 exponent;
 	s32 mantissa;
@@ -397,15 +397,15 @@
 	else
 		val >>= -exponent;
 
-	return (int)val;
+	return val;
 }
 
 /*
  * Convert direct sensor values to milli- or micro-units
  * depending on sensor type.
  */
-static int pmbus_reg2data_direct(struct pmbus_data *data,
-				 struct pmbus_sensor *sensor)
+static long pmbus_reg2data_direct(struct pmbus_data *data,
+				  struct pmbus_sensor *sensor)
 {
 	long val = (s16) sensor->data;
 	long m, b, R;
@@ -440,12 +440,12 @@
 		R++;
 	}
 
-	return (int)((val - b) / m);
+	return (val - b) / m;
 }
 
-static int pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
+static long pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
 {
-	int val;
+	long val;
 
 	if (data->info->direct[sensor->class])
 		val = pmbus_reg2data_direct(data, sensor);
@@ -619,7 +619,7 @@
 	if (!s1 && !s2)
 		*val = !!regval;
 	else {
-		int v1, v2;
+		long v1, v2;
 		struct pmbus_sensor *sensor1, *sensor2;
 
 		sensor1 = &data->sensors[s1];
@@ -661,7 +661,7 @@
 	if (sensor->data < 0)
 		return sensor->data;
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", pmbus_reg2data(data, sensor));
+	return snprintf(buf, PAGE_SIZE, "%ld\n", pmbus_reg2data(data, sensor));
 }
 
 static ssize_t pmbus_set_sensor(struct device *dev,