1 files changed, 45 insertions, 10 deletions

diff --git a/drivers/thermal/thermal_trip.c b/drivers/thermal/thermal_trip.c
index 024e2e365a26..e42456442c68 100644
--- a/drivers/thermal/thermal_trip.c
+++ b/drivers/thermal/thermal_trip.c
@@ -13,15 +13,11 @@ int for_each_thermal_trip(struct thermal_zone_device *tz,
 			  int (*cb)(struct thermal_trip *, void *),
 			  void *data)
 {
-	int i, ret;
-
-	lockdep_assert_held(&tz->lock);
-
-	if (!tz->trips)
-		return -ENODATA;
+	struct thermal_trip *trip;
+	int ret;
 
-	for (i = 0; i < tz->num_trips; i++) {
-		ret = cb(&tz->trips[i], data);
+	for_each_trip(tz, trip) {
+		ret = cb(trip, data);
 		if (ret)
 			return ret;
 	}
@@ -30,6 +26,20 @@ int for_each_thermal_trip(struct thermal_zone_device *tz,
 }
 EXPORT_SYMBOL_GPL(for_each_thermal_trip);
 
+int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
+			       int (*cb)(struct thermal_trip *, void *),
+			       void *data)
+{
+	int ret;
+
+	mutex_lock(&tz->lock);
+	ret = for_each_thermal_trip(tz, cb, data);
+	mutex_unlock(&tz->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(thermal_zone_for_each_trip);
+
 int thermal_zone_get_num_trips(struct thermal_zone_device *tz)
 {
 	return tz->num_trips;
@@ -55,6 +65,7 @@ void __thermal_zone_set_trips(struct thermal_zone_device *tz)
 {
 	struct thermal_trip trip;
 	int low = -INT_MAX, high = INT_MAX;
+	bool same_trip = false;
 	int i, ret;
 
 	lockdep_assert_held(&tz->lock);
@@ -63,6 +74,7 @@ void __thermal_zone_set_trips(struct thermal_zone_device *tz)
 		return;
 
 	for (i = 0; i < tz->num_trips; i++) {
+		bool low_set = false;
 		int trip_low;
 
 		ret = __thermal_zone_get_trip(tz, i , &trip);
@@ -71,18 +83,31 @@ void __thermal_zone_set_trips(struct thermal_zone_device *tz)
 
 		trip_low = trip.temperature - trip.hysteresis;
 
-		if (trip_low < tz->temperature && trip_low > low)
+		if (trip_low < tz->temperature && trip_low > low) {
 			low = trip_low;
+			low_set = true;
+			same_trip = false;
+		}
 
 		if (trip.temperature > tz->temperature &&
-		    trip.temperature < high)
+		    trip.temperature < high) {
 			high = trip.temperature;
+			same_trip = low_set;
+		}
 	}
 
 	/* No need to change trip points */
 	if (tz->prev_low_trip == low && tz->prev_high_trip == high)
 		return;
 
+	/*
+	 * If "high" and "low" are the same, skip the change unless this is the
+	 * first time.
+	 */
+	if (same_trip && (tz->prev_low_trip != -INT_MAX ||
+	    tz->prev_high_trip != INT_MAX))
+		return;
+
 	tz->prev_low_trip = low;
 	tz->prev_high_trip = high;
 
@@ -160,3 +185,13 @@ int thermal_zone_set_trip(struct thermal_zone_device *tz, int trip_id,
 
 	return 0;
 }
+
+int thermal_zone_trip_id(struct thermal_zone_device *tz,
+			 const struct thermal_trip *trip)
+{
+	/*
+	 * Assume the trip to be located within the bounds of the thermal
+	 * zone's trips[] table.
+	 */
+	return trip - tz->trips;
+}