[PATCH 1/2] rkvdec: h264: Refuse to decode unsupported bitstream

From: Ezequiel Garcia
Date: Fri Jun 26 2020 - 13:12:31 EST


The hardware only supports 4:2:2, 4:2:0 or 4:0:0 (monochrome),
8-bit or 10-bit depth content.

Verify that the PPS refers to a supported bitstream, and refuse
unsupported bitstreams by failing at TRY_EXT_CTRLS time.

The driver is currently broken on 10-bit and 4:2:2
so disallow those as well.

Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
---
drivers/staging/media/rkvdec/rkvdec.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)

diff --git a/drivers/staging/media/rkvdec/rkvdec.c b/drivers/staging/media/rkvdec/rkvdec.c
index 225eeca73356..0f81b47792f6 100644
--- a/drivers/staging/media/rkvdec/rkvdec.c
+++ b/drivers/staging/media/rkvdec/rkvdec.c
@@ -27,6 +27,32 @@
#include "rkvdec.h"
#include "rkvdec-regs.h"

+static int rkvdec_try_ctrl(struct v4l2_ctrl *ctrl)
+{
+ if (ctrl->id == V4L2_CID_MPEG_VIDEO_H264_SPS) {
+ const struct v4l2_ctrl_h264_sps *sps = ctrl->p_cur.p;
+ /*
+ * TODO: The hardware supports 10-bit and 4:2:2 profiles,
+ * but it's currently broken in the driver.
+ * Reject them for now, until it's fixed.
+ */
+ if (sps->chroma_format_idc > 1)
+ /* Only 4:0:0 and 4:2:0 are supported */
+ return -EINVAL;
+ if (sps->bit_depth_luma_minus8 != sps->bit_depth_chroma_minus8)
+ /* Luma and chroma bit depth mismatch */
+ return -EINVAL;
+ if (sps->bit_depth_luma_minus8 != 0)
+ /* Only 8-bit is supported */
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static const struct v4l2_ctrl_ops rkvdec_ctrl_ops = {
+ .try_ctrl = rkvdec_try_ctrl,
+};
+
static const struct rkvdec_ctrl_desc rkvdec_h264_ctrl_descs[] = {
{
.per_request = true,
@@ -42,6 +68,7 @@ static const struct rkvdec_ctrl_desc rkvdec_h264_ctrl_descs[] = {
.per_request = true,
.mandatory = true,
.cfg.id = V4L2_CID_MPEG_VIDEO_H264_SPS,
+ .cfg.ops = &rkvdec_ctrl_ops,
},
{
.per_request = true,
--
2.26.0.rc2