thermal: core: Add function to walk trips under zone lock

Add a wrapper around for_each_thermal_trip(), called
thermal_zone_for_each_trip(), that will invoke the former under the
thermal zone lock and pass its return value to the caller.

Two drivers will be modified subsequently to use this new function.

No functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>

drivers/thermal/thermal_trip.c

@@ -27,6 +27,20 @@ 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;

include/linux/thermal.h

@@ -286,6 +286,9 @@ int thermal_zone_set_trip(struct thermal_zone_device *tz, int trip_id,
 int for_each_thermal_trip(struct thermal_zone_device *tz,
 			  int (*cb)(struct thermal_trip *, void *),
 			  void *data);
+int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
+			       int (*cb)(struct thermal_trip *, void *),
+			       void *data);
 int thermal_zone_get_num_trips(struct thermal_zone_device *tz);
 
 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp);