>The HEVC HANTRO driver needs to know the number of bits to skip at
>the beginning of the slice header.
>That is a hardware specific requirement so create a dedicated control
>for this purpose.
>
>Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
>---
> .../userspace-api/media/drivers/hantro.rst | 19 +++++++++++++++++++
> .../userspace-api/media/drivers/index.rst | 1 +
> include/media/hevc-ctrls.h | 13 +++++++++++++
> 3 files changed, 33 insertions(+)
> create mode 100644 Documentation/userspace-api/media/drivers/hantro.rst
>
>diff --git a/Documentation/userspace-api/media/drivers/hantro.rst b/Documentation/userspace-api/media/drivers/hantro.rst
>new file mode 100644
>index 000000000000..cd9754b4e005
>--- /dev/null
>+++ b/Documentation/userspace-api/media/drivers/hantro.rst
>@@ -0,0 +1,19 @@
>+.. SPDX-License-Identifier: GPL-2.0
>+
>+Hantro video decoder driver
>+===========================
>+
>+The Hantro video decoder driver implements the following driver-specific controls:
>+
>+``V4L2_CID_HANTRO_HEVC_SLICE_HEADER_SKIP (integer)``
>+ Specifies to Hantro HEVC video decoder driver the number of data (in bits) to
>+ skip in the slice segment header.
>+ If non-IDR, the bits to be skipped go from syntax element "pic_output_flag"
>+ to before syntax element "slice_temporal_mvp_enabled_flag".
>+ If IDR, the skipped bits are just "pic_output_flag"
>+ (separate_colour_plane_flag is not supported).
What happens if it is a dependant_slice_segement or
output_flag_present_flag? Those flags are all dependant on
dependant_slice_segement being false. I'm guessing 0 but it maybe
should be documented.
Likewise if output_flag_present_flag is false pic_output_flag will not
be coded, so maybe express it as "after slice_type" rather than "before
pic_output_flag"?
Regards
John Cox
>+.. note::
>+
>+ This control is not yet part of the public kernel API and
>+ it is expected to change.
>diff --git a/Documentation/userspace-api/media/drivers/index.rst b/Documentation/userspace-api/media/drivers/index.rst
>index 1a9038f5f9fa..12e3c512d718 100644
>--- a/Documentation/userspace-api/media/drivers/index.rst
>+++ b/Documentation/userspace-api/media/drivers/index.rst
>@@ -33,6 +33,7 @@ For more details see the file COPYING in the source distribution of Linux.
>
> ccs
> cx2341x-uapi
>+ hantro
> imx-uapi
> max2175
> meye-uapi
>diff --git a/include/media/hevc-ctrls.h b/include/media/hevc-ctrls.h
>index 8e0109eea454..b713eeed1915 100644
>--- a/include/media/hevc-ctrls.h
>+++ b/include/media/hevc-ctrls.h
>@@ -224,4 +224,17 @@ struct v4l2_ctrl_hevc_decode_params {
> __u64 flags;
> };
>
>+/* MPEG-class control IDs specific to the Hantro driver as defined by V4L2 */
>+#define V4L2_CID_CODEC_HANTRO_BASE (V4L2_CTRL_CLASS_CODEC | 0x1200)
>+/*
>+ * V4L2_CID_HANTRO_HEVC_SLICE_HEADER_SKIP -
>+ * the number of data (in bits) to skip in the
>+ * slice segment header.
>+ * If non-IDR, the bits to be skipped go from syntax element "pic_output_flag"
>+ * to before syntax element "slice_temporal_mvp_enabled_flag".
>+ * If IDR, the skipped bits are just "pic_output_flag"
>+ * (separate_colour_plane_flag is not supported).
>+ */
>+#define V4L2_CID_HANTRO_HEVC_SLICE_HEADER_SKIP (V4L2_CID_CODEC_HANTRO_BASE + 0)
>+
> #endif
