V4L/DVB (9957): v4l2-subdev: add g_sliced_vbi_cap and add NULL pointer checks

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index bc9e0fb..bca25e8 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -110,6 +110,7 @@
 	int (*decode_vbi_line)(struct v4l2_subdev *sd, struct v4l2_decode_vbi_line *vbi_line);
 	int (*s_vbi_data)(struct v4l2_subdev *sd, const struct v4l2_sliced_vbi_data *vbi_data);
 	int (*g_vbi_data)(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_data *vbi_data);
+	int (*g_sliced_vbi_cap)(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_cap *cap);
 	int (*s_std_output)(struct v4l2_subdev *sd, v4l2_std_id std);
 	int (*s_stream)(struct v4l2_subdev *sd, int enable);
 	int (*s_fmt)(struct v4l2_subdev *sd, struct v4l2_format *fmt);