hwmon: (adm1029) Use mask for fan_div value

This is my patch for testing correct values of fan div in adm1029 and
prevent a division by 0 for some (unlikely) register values.

Signed-off-by: Corentin Labbe <corentin.labbe@geomatys.fr>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/drivers/hwmon/adm1029.c b/drivers/hwmon/adm1029.c
index ba84ca5923f9..36718150b475 100644
--- a/drivers/hwmon/adm1029.c
+++ b/drivers/hwmon/adm1029.c
@@ -179,7 +179,8 @@ show_fan(struct device *dev, struct device_attribute *devattr, char *buf)
         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
         struct adm1029_data *data = adm1029_update_device(dev);
         u16 val;
-        if (data->fan[attr->index] == 0 || data->fan_div[attr->index] == 0
+        if (data->fan[attr->index] == 0
+            || (data->fan_div[attr->index] & 0xC0) == 0
             || data->fan[attr->index] == 255) {
                 return sprintf(buf, "0\n");
         }
@@ -194,7 +195,7 @@ show_fan_div(struct device *dev, struct device_attribute *devattr, char *buf)
 {
         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
         struct adm1029_data *data = adm1029_update_device(dev);
-        if (data->fan_div[attr->index] == 0)
+        if ((data->fan_div[attr->index] & 0xC0) == 0)
                 return sprintf(buf, "0\n");
         return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[attr->index]));
 }