PowerCap: Fix mode for energy counter

As per the documentation of powercap sysfs, energy_uj field is read only, if it can't be reset. Currently it always allows write but will fail, if there is no reset callback. Changing mode field, to read only if there is no reset callback. Signed-off-by: Srinivas Pandruvada <[email protected]> Reported-by: Dirk Brandewie <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
chewitt · Dec 5, 2013 · 95677a9 · 95677a9
1 parent 08ff4cb
commit 95677a9
Showing 1 changed file with 6 additions and 1 deletion.
diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c
@@ -377,9 +377,14 @@ static void create_power_zone_common_attributes(
 	if (power_zone->ops->get_max_energy_range_uj)
 		power_zone->zone_dev_attrs[count++] =
 					&dev_attr_max_energy_range_uj.attr;
-	if (power_zone->ops->get_energy_uj)
+	if (power_zone->ops->get_energy_uj) {
+		if (power_zone->ops->reset_energy_uj)
+			dev_attr_energy_uj.attr.mode = S_IWUSR | S_IRUGO;
+		else
+			dev_attr_energy_uj.attr.mode = S_IRUGO;
 		power_zone->zone_dev_attrs[count++] =
 					&dev_attr_energy_uj.attr;
+	}
 	if (power_zone->ops->get_power_uw)
 		power_zone->zone_dev_attrs[count++] =
 					&dev_attr_power_uw.attr;