[v7,09/13] media: uapi: Add a control for HANTRO driver

Commit Message

Benjamin Gaignard March 29, 2021, 6:57 a.m. UTC

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
that this purpose.

Signed-off-by: Benjamin Gaignard <[e-mail]>
---
version 5:
 - Be even more verbose in control documentation.
 - Do not create class for the control.
version 4:
- The control is now an integer which is enough to provide the numbers
  of bits to skip.
version 3:
- Fix typo in field name

 .../userspace-api/media/drivers/hantro.rst         | 14 ++++++++++++++
 .../userspace-api/media/drivers/index.rst          |  1 +
 include/uapi/linux/v4l2-controls.h                 | 13 +++++++++++++
 3 files changed, 28 insertions(+)
 create mode 100644 Documentation/userspace-api/media/drivers/hantro.rst

Patch

diff --git a/Documentation/userspace-api/media/drivers/hantro.rst b/Documentation/userspace-api/media/drivers/hantro.rst
new file mode 100644
index 000000000000..78dcd2a44a03
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/hantro.rst
@@ -0,0 +1,14 @@ 
+.. 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).
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/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
index f3376aafea65..1dfb874b6272 100644
--- a/include/uapi/linux/v4l2-controls.h
+++ b/include/uapi/linux/v4l2-controls.h
@@ -869,6 +869,19 @@  enum v4l2_mpeg_mfc51_video_force_frame_type {
 #define V4L2_CID_MPEG_MFC51_VIDEO_H264_ADAPTIVE_RC_STATIC		(V4L2_CID_CODEC_MFC51_BASE+53)
 #define V4L2_CID_MPEG_MFC51_VIDEO_H264_NUM_REF_PIC_FOR_P		(V4L2_CID_CODEC_MFC51_BASE+54)
 
+/*  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)
+
 /*  Camera class control IDs */
 
 #define V4L2_CID_CAMERA_CLASS_BASE	(V4L2_CTRL_CLASS_CAMERA | 0x900)