thermal: core: Introduce thermal_zone_device_exec()

Introduce a new helper function, thermal_zone_device_exec(), that can
be used by drivers to run a given callback routine under the zone lock.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/thermal/thermal_core.c

@@ -497,6 +497,25 @@ void thermal_zone_device_update(struct thermal_zone_device *tz,
 }
 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 
+/**
+ * thermal_zone_device_exec - Run a callback under the zone lock.
+ * @tz: Thermal zone.
+ * @cb: Callback to run.
+ * @data: Data to pass to the callback.
+ */
+void thermal_zone_device_exec(struct thermal_zone_device *tz,
+			      void (*cb)(struct thermal_zone_device *,
+					 unsigned long),
+			      unsigned long data)
+{
+	mutex_lock(&tz->lock);
+
+	cb(tz, data);
+
+	mutex_unlock(&tz->lock);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_exec);
+
 static void thermal_zone_device_check(struct work_struct *work)
 {
 	struct thermal_zone_device *tz = container_of(work, struct

include/linux/thermal.h

@@ -323,6 +323,10 @@ int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
 				       struct thermal_cooling_device *);
 void thermal_zone_device_update(struct thermal_zone_device *,
 				enum thermal_notify_event);
+void thermal_zone_device_exec(struct thermal_zone_device *tz,
+			      void (*cb)(struct thermal_zone_device *,
+					 unsigned long),
+			      unsigned long data);
 
 struct thermal_cooling_device *thermal_cooling_device_register(const char *,
 		void *, const struct thermal_cooling_device_ops *);