[PATCH 5/8] media: uapi: HEVC: Add v4l2_ctrl_hevc_ext_sps_rps control

From: Detlev Casanova
Date: Mon Jun 23 2025 - 12:13:36 EST


Some hardware (e.g.: Rockchip's rk3588 hevc decoder) need the parsed
long and short term reference information for HEVC decoding.

Signed-off-by: Detlev Casanova <detlev.casanova@xxxxxxxxxxxxx>
---
.../media/v4l/ext-ctrls-codec-stateless.rst | 73 +++++++++++++++++++
.../media/v4l/vidioc-queryctrl.rst | 6 ++
2 files changed, 79 insertions(+)

diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst
index 0da635691fdcb..745f38a8fe69c 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec-stateless.rst
@@ -2958,6 +2958,79 @@ This structure contains all loop filter related parameters. See sections
- 0x00000004
-

+.. c:type:: v4l2_ctrl_hevc_ext_sps_rps
+
+.. cssclass:: longtable
+
+.. flat-table:: struct v4l2_ctrl_hevc_ext_sps_rps
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u16
+ - ``lt_ref_pic_poc_lsb_sps``
+ - Long term reference picture order count as described in section 7.4.3.2.1
+ "General sequence parameter set RBSP semantics" of the specification.
+ * - __u8
+ - ``delta_idx_minus1``
+ - Specifies the delta compare to the index. See details in section 7.4.8 "Short-term
+ reference picture set semantics" of the specification.
+ * - __u8
+ - ``delta_rps_sign``
+ - Sign of the delta as specified in section 7.4.8 "Short-term reference picture set
+ semantics" of the specification.
+ * - __u16
+ - ``abs_delta_rps_minus1``
+ - Absolute delta RPS as specified in section 7.4.8 "Short-term reference picture set
+ semantics" of the specification.
+ * - __u8
+ - ``num_negative_pics``
+ - Number of short-term RPS entries that have picture order count values less than the
+ picture order count value of the current picture.
+ * - __u8
+ - ``num_positive_pics``
+ - Number of short-term RPS entries that have picture order count values greater than the
+ picture order count value of the current picture.
+ * - __u8
+ - ``used_by_curr_pic_s0[16]``
+ - Specifies if short-term RPS i (that has a negative POC) is used by the current picture.
+ * - __u8
+ - ``used_by_curr_pic_s1[16]``
+ - Specifies if short-term RPS i (that has a positive POC) is used by the current picture.
+ * - __s32
+ - ``delta_poc_s0[16]``
+ - Specifies the negative picture order count delta for the i-th entry in the short-term RPS.
+ See details in section 7.4.8 "Short-term reference picture set semantics" of the
+ specification.
+ * - __s32
+ - ``delta_poc_s1[16]``
+ - Specifies the positive picture order count delta for the i-th entry in the short-term RPS.
+ See details in section 7.4.8 "Short-term reference picture set semantics" of the
+ specification.
+ * - __u8
+ - ``flags``
+ - See :ref:`Extended RPS Flags <hevc_ext_sps_rps_flags>`
+
+.. _hevc_ext_sps_rps_flags:
+
+``Extended SPS RPS Flags``
+
+.. cssclass:: longtable
+
+.. flat-table::
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - ``V4L2_HEVC_EXT_SPS_RPS_FLAG_USED_LT``
+ - 0x00000001
+ - Specifies if the long-term reference picture is used 7.4.3.2.1 "General sequence parameter
+ set RBSP semantics" of the specification.
+ * - ``V4L2_HEVC_EXT_SPS_RPS_FLAG_INTER_REF_PIC_SET_PRED``
+ - 0x00000002
+ - Specifies if the short-term RPS is predicted from another short term RPS. See details in
+ section 7.4.8 "Short-term reference picture set semantics" of the specification.
+
.. _v4l2-codec-stateless-av1:

``V4L2_CID_STATELESS_AV1_SEQUENCE (struct)``
diff --git a/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst b/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst
index 3549417c7febb..dc7caf4bf6208 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-queryctrl.rst
@@ -523,6 +523,12 @@ See also the examples in :ref:`control`.
- n/a
- A struct :c:type:`v4l2_ctrl_hevc_decode_params`, containing HEVC
decoding parameters for stateless video decoders.
+ * - ``V4L2_CTRL_TYPE_HEVC_EXT_SPS_RPS``
+ - n/a
+ - n/a
+ - n/a
+ - A struct :c:type:`v4l2_ctrl_hevc_ext_sps_rps`, containing HEVC
+ extended RPS for stateless video decoders.
* - ``V4L2_CTRL_TYPE_VP9_COMPRESSED_HDR``
- n/a
- n/a
--
2.50.0