thermal/core: Add thermal_zone_device structure 'type' accessor

The thermal zone device structure is exposed via the exported
thermal.h header. This structure should stay private the thermal core
code. In order to encapsulate the structure, let's add an accessor to
get the 'type' of the thermal zone.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/thermal/thermal_core.c

@@ -1383,6 +1383,12 @@ void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
 }
 EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
 
+const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
+{
+	return tzd->type;
+}
+EXPORT_SYMBOL_GPL(thermal_zone_device_type);
+
 /**
  * thermal_zone_device_unregister - removes the registered thermal zone device
  * @tz: the thermal zone device to remove

include/linux/thermal.h

@@ -366,6 +366,7 @@ thermal_zone_device_register_with_trips(const char *, struct thermal_trip *, int
 					struct thermal_zone_params *, int, int);
 
 void *thermal_zone_device_priv(struct thermal_zone_device *tzd);
+const char *thermal_zone_device_type(struct thermal_zone_device *tzd);
 
 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
 				     struct thermal_cooling_device *,
@@ -443,6 +444,11 @@ static inline void *thermal_zone_device_priv(struct thermal_zone_device *tz)
 	return NULL;
 }
 
+static inline const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
+{
+	return NULL;
+}
+
 static inline int thermal_zone_device_enable(struct thermal_zone_device *tz)
 { return -ENODEV; }