media: v4l: Add definitions for MPEG-2 slice format and metadata

Stateless video decoding engines require both the MPEG-2 slices and
associated metadata from the video stream in order to decode frames.

This introduces definitions for a new pixel format, describing buffers
with MPEG-2 slice data, as well as control structure sfor passing the
frame metadata to drivers.

This is based on work from both Florent Revest and Hugues Fruchet.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

2 files changed, 64 insertions, 0 deletions

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 5310ac857e83..65e3cf838ac7 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -844,6 +844,8 @@ const char *v4l2_ctrl_get_name(u32 id)
 	case V4L2_CID_MPEG_VIDEO_MV_V_SEARCH_RANGE:		return "Vertical MV Search Range";
 	case V4L2_CID_MPEG_VIDEO_REPEAT_SEQ_HEADER:		return "Repeat Sequence Header";
 	case V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME:		return "Force Key Frame";
+	case V4L2_CID_MPEG_VIDEO_MPEG2_SLICE_PARAMS:		return "MPEG-2 Slice Parameters";
+	case V4L2_CID_MPEG_VIDEO_MPEG2_QUANTIZATION:		return "MPEG-2 Quantization Matrices";
 
 	/* VPX controls */
 	case V4L2_CID_MPEG_VIDEO_VPX_NUM_PARTITIONS:		return "VPX Number of Partitions";
@@ -1292,6 +1294,12 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
 	case V4L2_CID_RDS_TX_ALT_FREQS:
 		*type = V4L2_CTRL_TYPE_U32;
 		break;
+	case V4L2_CID_MPEG_VIDEO_MPEG2_SLICE_PARAMS:
+		*type = V4L2_CTRL_TYPE_MPEG2_SLICE_PARAMS;
+		break;
+	case V4L2_CID_MPEG_VIDEO_MPEG2_QUANTIZATION:
+		*type = V4L2_CTRL_TYPE_MPEG2_QUANTIZATION;
+		break;
 	default:
 		*type = V4L2_CTRL_TYPE_INTEGER;
 		break;
@@ -1550,6 +1558,7 @@ static void std_log(const struct v4l2_ctrl *ctrl)
 static int std_validate(const struct v4l2_ctrl *ctrl, u32 idx,
 			union v4l2_ctrl_ptr ptr)
 {
+	struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
 	size_t len;
 	u64 offset;
 	s64 val;
@@ -1612,6 +1621,54 @@ static int std_validate(const struct v4l2_ctrl *ctrl, u32 idx,
 			return -ERANGE;
 		return 0;
 
+	case V4L2_CTRL_TYPE_MPEG2_SLICE_PARAMS:
+		p_mpeg2_slice_params = ptr.p;
+
+		switch (p_mpeg2_slice_params->sequence.chroma_format) {
+		case 1: /* 4:2:0 */
+		case 2: /* 4:2:2 */
+		case 3: /* 4:4:4 */
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		switch (p_mpeg2_slice_params->picture.intra_dc_precision) {
+		case 0: /* 8 bits */
+		case 1: /* 9 bits */
+		case 11: /* 11 bits */
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		switch (p_mpeg2_slice_params->picture.picture_structure) {
+		case 1: /* interlaced top field */
+		case 2: /* interlaced bottom field */
+		case 3: /* progressive */
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		switch (p_mpeg2_slice_params->picture.picture_coding_type) {
+		case V4L2_MPEG2_PICTURE_CODING_TYPE_I:
+		case V4L2_MPEG2_PICTURE_CODING_TYPE_P:
+		case V4L2_MPEG2_PICTURE_CODING_TYPE_B:
+			break;
+		default:
+			return -EINVAL;
+		}
+
+		if (p_mpeg2_slice_params->backward_ref_index >= VIDEO_MAX_FRAME ||
+		    p_mpeg2_slice_params->forward_ref_index >= VIDEO_MAX_FRAME)
+			return -EINVAL;
+
+		return 0;
+
+	case V4L2_CTRL_TYPE_MPEG2_QUANTIZATION:
+		return 0;
+
 	default:
 		return -EINVAL;
 	}
@@ -2186,6 +2243,12 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
 	case V4L2_CTRL_TYPE_U32:
 		elem_size = sizeof(u32);
 		break;
+	case V4L2_CTRL_TYPE_MPEG2_SLICE_PARAMS:
+		elem_size = sizeof(struct v4l2_ctrl_mpeg2_slice_params);
+		break;
+	case V4L2_CTRL_TYPE_MPEG2_QUANTIZATION:
+		elem_size = sizeof(struct v4l2_ctrl_mpeg2_quantization);
+		break;
 	default:
 		if (type < V4L2_CTRL_COMPOUND_TYPES)
 			elem_size = sizeof(s32);
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 87dba0b9c0a7..1a8feaf6c3f7 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1309,6 +1309,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
 		case V4L2_PIX_FMT_H263:		descr = "H.263"; break;
 		case V4L2_PIX_FMT_MPEG1:	descr = "MPEG-1 ES"; break;
 		case V4L2_PIX_FMT_MPEG2:	descr = "MPEG-2 ES"; break;
+		case V4L2_PIX_FMT_MPEG2_SLICE:	descr = "MPEG-2 Parsed Slice Data"; break;
 		case V4L2_PIX_FMT_MPEG4:	descr = "MPEG-4 part 2 ES"; break;
 		case V4L2_PIX_FMT_XVID:		descr = "Xvid"; break;
 		case V4L2_PIX_FMT_VC1_ANNEX_G:	descr = "VC-1 (SMPTE 412M Annex G)"; break;