media: v4l2-ctrl: Add control to enable h.264 constrained intra prediction

Allow to enable h.264 constrained intra prediction (macroblocks using
intra prediction modes are not allowed to use residual data and decoded
samples of neighboring macroblocks coded using inter prediction modes).
This control directly corresponds to the constrained_intra_pred_flag
field in the h.264 picture parameter set.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

Documentation/media/uapi/v4l/extended-controls.rst

@@ -1154,6 +1154,10 @@ enum v4l2_mpeg_video_h264_entropy_mode -
 ``V4L2_CID_MPEG_VIDEO_H264_8X8_TRANSFORM (boolean)``
     Enable 8X8 transform for H264. Applicable to the H264 encoder.
 
+``V4L2_CID_MPEG_VIDEO_H264_CONSTRAINED_INTRA_PREDICTION (boolean)``
+    Enable constrained intra prediction for H264. Applicable to the H264
+    encoder.
+
 ``V4L2_CID_MPEG_VIDEO_CYCLIC_INTRA_REFRESH_MB (integer)``
     Cyclic intra macroblock refresh. This is the number of continuous
     macroblocks refreshed every frame. Each frame a successive set of

drivers/media/v4l2-core/v4l2-ctrls.c

@@ -825,6 +825,8 @@ const char *v4l2_ctrl_get_name(u32 id)
 	case V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER:return "H264 Number of HC Layers";
 	case V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP:
 								return "H264 Set QP Value for HC Layers";
+	case V4L2_CID_MPEG_VIDEO_H264_CONSTRAINED_INTRA_PREDICTION:
+								return "H264 Constrained Intra Pred";
 	case V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP:		return "MPEG4 I-Frame QP Value";
 	case V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP:		return "MPEG4 P-Frame QP Value";
 	case V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP:		return "MPEG4 B-Frame QP Value";

include/uapi/linux/v4l2-controls.h

@@ -533,6 +533,7 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type {
 };
 #define V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER	(V4L2_CID_MPEG_BASE+381)
 #define V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP	(V4L2_CID_MPEG_BASE+382)
+#define V4L2_CID_MPEG_VIDEO_H264_CONSTRAINED_INTRA_PREDICTION	(V4L2_CID_MPEG_BASE+383)
 #define V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP	(V4L2_CID_MPEG_BASE+400)
 #define V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP	(V4L2_CID_MPEG_BASE+401)
 #define V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP	(V4L2_CID_MPEG_BASE+402)