hwmon: (pmbus_core) Fix compiler warning

Some configurations produce the following compiler warning:

drivers/hwmon/pmbus/pmbus_core.c: In function 'pmbus_show_boolean':
drivers/hwmon/pmbus/pmbus_core.c:752: warning: 'val' may be used uninitialized in this function

While this is a false positive, it can easily be fixed by overloading the return
value from pmbus_get_boolean with both val and error return code (val is a
boolean and thus never negative).

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index be51037..29b319d 100644 (file)
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -710,13 +710,13 @@ static u16 pmbus_data2reg(struct pmbus_data *data,
  * If a negative value is stored in any of the referenced registers, this value
  * reflects an error code which will be returned.
  */
-static int pmbus_get_boolean(struct pmbus_data *data, int index, int *val)
+static int pmbus_get_boolean(struct pmbus_data *data, int index)
 {
        u8 s1 = (index >> 24) & 0xff;
        u8 s2 = (index >> 16) & 0xff;
        u8 reg = (index >> 8) & 0xff;
        u8 mask = index & 0xff;
-       int status;
+       int ret, status;
        u8 regval;
 
        status = data->status[reg];
@@ -725,7 +725,7 @@ static int pmbus_get_boolean(struct pmbus_data *data, int index, int *val)
 
        regval = status & mask;
        if (!s1 && !s2)
-               *val = !!regval;
+               ret = !!regval;
        else {
                long v1, v2;
                struct pmbus_sensor *sensor1, *sensor2;
@@ -739,9 +739,9 @@ static int pmbus_get_boolean(struct pmbus_data *data, int index, int *val)
 
                v1 = pmbus_reg2data(data, sensor1);
                v2 = pmbus_reg2data(data, sensor2);
-               *val = !!(regval && v1 >= v2);
+               ret = !!(regval && v1 >= v2);
        }
-       return 0;
+       return ret;
 }
 
 static ssize_t pmbus_show_boolean(struct device *dev,
@@ -750,11 +750,10 @@ static ssize_t pmbus_show_boolean(struct device *dev,
        struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
        struct pmbus_data *data = pmbus_update_device(dev);
        int val;
-       int err;
 
-       err = pmbus_get_boolean(data, attr->index, &val);
-       if (err)
-               return err;
+       val = pmbus_get_boolean(data, attr->index);
+       if (val < 0)
+               return val;
        return snprintf(buf, PAGE_SIZE, "%d\n", val);
 }