diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h
index 5d7146d..3d8e96f 100644
--- a/include/media/v4l2-device.h
+++ b/include/media/v4l2-device.h
@@ -44,6 +44,9 @@
 	spinlock_t lock;
 	/* unique device name, by default the driver name + bus ID */
 	char name[V4L2_DEVICE_NAME_SIZE];
+	/* notify callback called by some sub-devices. */
+	void (*notify)(struct v4l2_subdev *sd,
+			unsigned int notification, void *arg);
 };
 
 /* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev.
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 05b6965..1b97a2c 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -191,4 +191,9 @@
 	(!(sd) ? -ENODEV : (((sd) && (sd)->ops->o && (sd)->ops->o->f) ?	\
 		(sd)->ops->o->f((sd) , ##args) : -ENOIOCTLCMD))
 
+/* Send a notification to v4l2_device. */
+#define v4l2_subdev_notify(sd, notification, arg)			   \
+	((!(sd) || !(sd)->v4l2_dev || !(sd)->v4l2_dev->notify) ? -ENODEV : \
+	 (sd)->v4l2_dev->notify((sd), (notification), (arg)))
+
 #endif