[media] mem2mem_testdev: add control events support

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/mem2mem_testdev.c

@@ -28,6 +28,7 @@
 #include <media/v4l2-device.h>
 #include <media/v4l2-ioctl.h>
 #include <media/v4l2-ctrls.h>
+#include <media/v4l2-event.h>
 #include <media/videobuf2-vmalloc.h>
 
 #define MEM2MEM_TEST_MODULE_NAME "mem2mem-testdev"
@@ -738,6 +739,8 @@ static const struct v4l2_ioctl_ops m2mtest_ioctl_ops = {
 
 	.vidioc_streamon	= vidioc_streamon,
 	.vidioc_streamoff	= vidioc_streamoff,
+	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
+	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 };