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Date:   Tue, 14 Jun 2022 15:39:21 +0200
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Subject: Re: [PATCH v8 08/17] media: uapi: HEVC: Add documentation to uAPI
 structure
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To:     Benjamin Gaignard <benjamin.gaignard@collabora.com>,
        mchehab@kernel.org, ezequiel@vanguardiasur.com.ar,
        p.zabel@pengutronix.de, gregkh@linuxfoundation.org,
        mripard@kernel.org, paul.kocialkowski@bootlin.com, wens@csie.org,
        jernej.skrabec@gmail.com, samuel@sholland.org,
        nicolas.dufresne@collabora.com, andrzej.p@collabora.com
Cc:     linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-rockchip@lists.infradead.org, linux-staging@lists.linux.dev,
        linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev,
        kernel@collabora.com
References: <20220614083614.240641-1-benjamin.gaignard@collabora.com>
 <20220614083614.240641-9-benjamin.gaignard@collabora.com>
From:   Hans Verkuil <hverkuil@xs4all.nl>
In-Reply-To: <20220614083614.240641-9-benjamin.gaignard@collabora.com>
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On 6/14/22 10:36, Benjamin Gaignard wrote:
> Add kernel-doc documentation for all the HEVC structures.
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
> ---
> version 5:
> - Fix num_short_term_ref_pic_sets and num_long_term_ref_pics_sps
> 
>  .../media/v4l/ext-ctrls-codec.rst             | 164 +++++++------
>  include/media/hevc-ctrls.h                    | 221 +++++++++++++++++-
>  2 files changed, 311 insertions(+), 74 deletions(-)
> 
> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> index 1ccf6dda61b3..06b967de140c 100644
> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> @@ -2695,70 +2695,76 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>          of H.265 specifications.
>      * - __u16
>        - ``pic_width_in_luma_samples``
> -      -
> +      - Specifies the width of each decoded picture in units of luma samples.
>      * - __u16
>        - ``pic_height_in_luma_samples``
> -      -
> +      - Specifies the height of each decoded picture in units of luma samples.
>      * - __u8
>        - ``bit_depth_luma_minus8``
> -      -
> +      - Specifies the bit depth of the samples of the luma array.

Shouldn't this be:

      - This value plus 8 specifies the bit depth of the samples of the luma array.

Same elsewhere.

>      * - __u8
>        - ``bit_depth_chroma_minus8``
> -      -
> +      - Specifies the bit depth of the samples of the chroma arrays.
>      * - __u8
>        - ``log2_max_pic_order_cnt_lsb_minus4``
> -      -
> +      - Specifies the value of the variable MaxPicOrderCntLsb.
>      * - __u8
>        - ``sps_max_dec_pic_buffering_minus1``
> -      -
> +      - Plus 1 specifies the maximum required size of the decoded picture buffer for

I would prefer to phrase this as: "This value plus 1"
I'm not sure how common the current phrase is, though. If it is already used everywhere,
then keep it as-is.

> +        the CVS

Missing period at the end.

What is CVS? Perhaps write the full name?

>      * - __u8
>        - ``sps_max_num_reorder_pics``
> -      -
> +      - Indicates the maximum allowed number of pictures.
>      * - __u8
>        - ``sps_max_latency_increase_plus1``
> -      -
> +      - Not equal to 0 is used to compute the value of SpsMaxLatencyPictures[i].
>      * - __u8
>        - ``log2_min_luma_coding_block_size_minus3``
> -      -
> +      - Plus 3 specifies the minimum luma coding block size.
>      * - __u8
>        - ``log2_diff_max_min_luma_coding_block_size``
> -      -
> +      - Specifies the difference between the maximum and minimum luma coding block size.
>      * - __u8
>        - ``log2_min_luma_transform_block_size_minus2``
> -      -
> +      - Plus 2 specifies the minimum luma transform block size.
>      * - __u8
>        - ``log2_diff_max_min_luma_transform_block_size``
> -      -
> +      - Specifies the difference between the maximum and minimum luma transform block size.
>      * - __u8
>        - ``max_transform_hierarchy_depth_inter``
> -      -
> +      - Specifies the maximum hierarchy depth for transform units of coding units coded
> +        in inter prediction mode.
>      * - __u8
>        - ``max_transform_hierarchy_depth_intra``
> -      -
> +      - Specifies the maximum hierarchy depth for transform units of coding units coded in
> +        intra prediction mode.
>      * - __u8
>        - ``pcm_sample_bit_depth_luma_minus1``
> -      -
> +      - Specifies the number of bits used to represent each of PCM sample values of the
> +        luma component.
>      * - __u8
>        - ``pcm_sample_bit_depth_chroma_minus1``
> -      -
> +      - Specifies the number of bits used to represent each of PCM sample values of
> +        the chroma components.
>      * - __u8
>        - ``log2_min_pcm_luma_coding_block_size_minus3``
> -      -
> +      - Plus 3 specifies the minimum size of coding blocks.
>      * - __u8
>        - ``log2_diff_max_min_pcm_luma_coding_block_size``
> -      -
> +      - Specifies the difference between the maximum and minimum size of coding blocks.
>      * - __u8
>        - ``num_short_term_ref_pic_sets``
> -      -
> +      - Specifies the number of st_ref_pic_set() syntax structures included in the SPS.
>      * - __u8
>        - ``num_long_term_ref_pics_sps``
> -      -
> +      - Specifies the number of candidate long-term reference pictures that are
> +        specified in the SPS.
>      * - __u8
>        - ``chroma_format_idc``
> -      -
> +      - Specifies the chroma sampling.
>      * - __u8
>        - ``sps_max_sub_layers_minus1``
> -      -
> +      - plus 1 specifies the maximum number of temporal sub-layers.

plus -> Plus

>      * - __u64
>        - ``flags``
>        - See :ref:`Sequence Parameter Set Flags <hevc_sps_flags>`
> @@ -2837,7 +2843,8 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>        - Identifies the PPS for reference by other syntax elements.
>      * - __u8
>        - ``num_extra_slice_header_bits``
> -      -
> +      - Specifies the number of extra slice header bits that are present
> +        in the slice header RBSP for coded pictures referring to the PPS.
>      * - __u8
>        - ``num_ref_idx_l0_default_active_minus1``
>        - Specifies the inferred value of num_ref_idx_l0_active_minus1
> @@ -2846,37 +2853,42 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>        - Specifies the inferred value of num_ref_idx_l1_active_minus1
>      * - __s8
>        - ``init_qp_minus26``
> -      -
> +      - Plus 26 specifies the initial value of SliceQp Y for each slice
> +        referring to the PPS.
>      * - __u8
>        - ``diff_cu_qp_delta_depth``
> -      -
> +      - Specifies the difference between the luma coding tree block size
> +        and the minimum luma coding block size of coding units that
> +        convey cu_qp_delta_abs and cu_qp_delta_sign_flag.
>      * - __s8
>        - ``pps_cb_qp_offset``
> -      -
> +      - Specify the offsets to the luma quantization parameter Cb.
>      * - __s8
>        - ``pps_cr_qp_offset``
> -      -
> +      - Specify the offsets to the luma quantization parameter Cr.
>      * - __u8
>        - ``num_tile_columns_minus1``
> -      -
> +      - Plus 1 specifies the number of tile columns partitioning the picture.
>      * - __u8
>        - ``num_tile_rows_minus1``
> -      -
> +      - Plus 1 specifies the number of tile rows partitioning the picture.
>      * - __u8
>        - ``column_width_minus1[20]``
> -      -
> +      - Plus 1 specifies the width of the i-th tile column in units of

Wouldn't "of each tile column" be easier to understand?

> +        coding tree blocks.
>      * - __u8
>        - ``row_height_minus1[22]``
> -      -
> +      - Plus 1 specifies the height of the i-th tile row in units of coding

Ditto.

> +        tree blocks.
>      * - __s8
>        - ``pps_beta_offset_div2``
> -      -
> +      - Specify the default deblocking parameter offsets for beta divided by 2.
>      * - __s8
>        - ``pps_tc_offset_div2``
> -      -
> +      - Specify the default deblocking parameter offsets for tC divided by 2.

Is it actually called 'tC' in the HEVC standard, or is this a typo?

>      * - __u8
>        - ``log2_parallel_merge_level_minus2``
> -      -
> +      - Plus 2 specifies the value of the variable Log2ParMrgLevel.
>      * - __u8
>        - ``padding[4]``
>        - Applications and drivers must set this to zero.
> @@ -2998,10 +3010,10 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>        - Offset (in bits) to the video data in the current slice data.
>      * - __u8
>        - ``nal_unit_type``
> -      -
> +      - Specifies the coding type of the slice (B, P or I).
>      * - __u8
>        - ``nuh_temporal_id_plus1``
> -      -
> +      - Minus 1 specifies a temporal identifier for the NAL unit.
>      * - __u8
>        - ``slice_type``
>        -
> @@ -3009,52 +3021,56 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>  	V4L2_HEVC_SLICE_TYPE_B).
>      * - __u8
>        - ``colour_plane_id``
> -      -
> +      - Specifies the colour plane associated with the current slice.
>      * - __s32
>        - ``slice_pic_order_cnt``
> -      -
> +      - Specifies the picture order count.
>      * - __u8
>        - ``num_ref_idx_l0_active_minus1``
> -      -
> +      - Specifies the maximum reference index for reference picture list 0
> +        that may be used to decode the slice.
>      * - __u8
>        - ``num_ref_idx_l1_active_minus1``
> -      -
> +      - Specifies the maximum reference index for reference picture list 1
> +        that may be used to decode the slice.
>      * - __u8
>        - ``collocated_ref_idx``
> -      -
> +      - Specifies the reference index of the collocated picture used for
> +        temporal motion vector prediction.
>      * - __u8
>        - ``five_minus_max_num_merge_cand``
> -      -
> +      - Specifies the maximum number of merging motion vector prediction
> +        candidates supported in the slice subtracted from 5.
>      * - __s8
>        - ``slice_qp_delta``
> -      -
> +      - Specifies the initial value of QpY to be used for the coding blocks in the slice.

It's really 'QpY'? There is no obvious relationship between the 'Y' character and the '_delta'
suffix. Just checking.

>      * - __s8
>        - ``slice_cb_qp_offset``
> -      -
> +      - Specifies a difference to be added to the value of pps_cb_qp_offset.
>      * - __s8
>        - ``slice_cr_qp_offset``
> -      -
> +      - Specifies a difference to be added to the value of pps_cr_qp_offset.
>      * - __s8
>        - ``slice_act_y_qp_offset``
> -      -
> +      - screen content extension parameters
>      * - __s8
>        - ``slice_act_cb_qp_offset``
> -      -
> +      - screen content extension parameters
>      * - __s8
>        - ``slice_act_cr_qp_offset``
> -      -
> +      - screen content extension parameters
>      * - __s8
>        - ``slice_beta_offset_div2``
> -      -
> +      - Specify the deblocking parameter offsets for beta divided by 2.
>      * - __s8
>        - ``slice_tc_offset_div2``
> -      -
> +      - Specify the deblocking parameter offsets for tC divided by 2.
>      * - __u8
>        - ``pic_struct``
> -      -
> +      - Indicates whether a picture should be displayed as a frame or as one or more fields.
>      * - __u32
>        - ``slice_segment_addr``
> -      -
> +      - Specifies the address of the first coding tree block in the slice segment.
>      * - __u8
>        - ``ref_idx_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
>        - The list of L0 reference elements as indices in the DPB.
> @@ -3219,11 +3235,9 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>        - ``field_pic``
>        - Whether the reference is a field picture or a frame.
>          See :ref:`HEVC dpb field pic Flags <hevc_dpb_field_pic_flags>`
> -    * - __u16
> -      - ``pic_order_cnt[2]``
> -      - The picture order count of the reference. Only the first element of the
> -        array is used for frame pictures, while the first element identifies the
> -        top field and the second the bottom field in field-coded pictures.
> +    * - __s32
> +      - ``pic_order_cnt_val``
> +      - The picture order count of the current picture.
>      * - __u8
>        - ``padding[2]``
>        - Applications and drivers must set this to zero.
> @@ -3298,36 +3312,44 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>      :stub-columns: 0
>      :widths:       1 1 2
>  
> -    * - __u8
> -      - ``luma_log2_weight_denom``
> -      -
> -    * - __s8
> -      - ``delta_chroma_log2_weight_denom``
> -      -
>      * - __s8
>        - ``delta_luma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
> -      -
> +      - The difference of the weighting factor applied to the luma
> +        prediction value for list 0.
>      * - __s8
>        - ``luma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
> -      -
> +      - The additive offset applied to the luma prediction value for list 0.
>      * - __s8
>        - ``delta_chroma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]``
> -      -
> +      - The difference of the weighting factor applied to the chroma
> +        prediction value for list 0.
>      * - __s8
>        - ``chroma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]``
> -      -
> +      - The difference of the additive offset applied to the chroma
> +        prediction values for list 0.
>      * - __s8
>        - ``delta_luma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
> -      -
> +      - The difference of the weighting factor applied to the luma
> +        prediction value for list 1.
>      * - __s8
>        - ``luma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]``
> -      -
> +      - The additive offset applied to the luma prediction value for list 1.
>      * - __s8
>        - ``delta_chroma_weight_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]``
> -      -
> +      - The difference of the weighting factor applied to the chroma
> +        prediction value for list 1.
>      * - __s8
>        - ``chroma_offset_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX][2]``
> -      -
> +      - The difference of the additive offset applied to the chroma
> +        prediction values for list 1.
> +    * - __u8
> +      - ``luma_log2_weight_denom``
> +      - The base 2 logarithm of the denominator for all luma weighting
> +        factors.
> +    * - __s8
> +      - ``delta_chroma_log2_weight_denom``
> +      - The difference of the base 2 logarithm of the denominator for
> +        all chroma weighting factors.
>      * - __u8
>        - ``padding[6]``
>        - Applications and drivers must set this to zero.
> diff --git a/include/media/hevc-ctrls.h b/include/media/hevc-ctrls.h
> index f3695ab44389..0dbd5d681c28 100644
> --- a/include/media/hevc-ctrls.h
> +++ b/include/media/hevc-ctrls.h
> @@ -55,9 +55,68 @@ enum v4l2_stateless_hevc_start_code {
>  #define V4L2_HEVC_SPS_FLAG_SPS_TEMPORAL_MVP_ENABLED		(1ULL << 7)
>  #define V4L2_HEVC_SPS_FLAG_STRONG_INTRA_SMOOTHING_ENABLED	(1ULL << 8)
>  
> -/* The controls are not stable at the moment and will likely be reworked. */
> +/**
> + * struct v4l2_ctrl_hevc_sps - ITU-T Rec. H.265: Sequence parameter set
> + *
> + * @video_parameter_set_id: specifies the value of the
> + *			    vps_video_parameter_set_id of the active VPS
> + * @seq_parameter_set_id: provides an identifier for the SPS for
> + *			  reference by other syntax elements
> + * @pic_width_in_luma_samples: specifies the width of each decoded picture
> + *			       in units of luma samples
> + * @pic_height_in_luma_samples: specifies the height of each decoded picture
> + *				in units of luma samples
> + * @bit_depth_luma_minus8: specifies the bit depth of the samples of the
> + *			   luma array
> + * @bit_depth_chroma_minus8: specifies the bit depth of the samples of the
> + *			     chroma arrays
> + * @log2_max_pic_order_cnt_lsb_minus4: specifies the value of the variable
> + *				       MaxPicOrderCntLsb
> + * @sps_max_dec_pic_buffering_minus1: plus 1 specifies the maximum required
> + *				      size of the decoded picture buffer for
> + *				      the CVS
> + * @sps_max_num_reorder_pics: indicates the maximum allowed number of pictures
> + * @sps_max_latency_increase_plus1: not equal to 0 is used to compute the
> + *				    value of SpsMaxLatencyPictures[i]

What is 'i' in this context?

> + * @log2_min_luma_coding_block_size_minus3: plus 3 specifies the minimum
> + *					    luma coding block size
> + * @log2_diff_max_min_luma_coding_block_size: specifies the difference between
> + *					      the maximum and minimum luma
> + *					      coding block size
> + * @log2_min_luma_transform_block_size_minus2: plus 2 specifies the minimum luma
> + *					       transform block size
> + * @log2_diff_max_min_luma_transform_block_size: specifies the difference between
> + *						 the maximum and minimum luma
> + *						 transform block size
> + * @max_transform_hierarchy_depth_inter: specifies the maximum hierarchy
> + *					 depth for transform units of
> + *					 coding units coded in inter
> + *					 prediction mode
> + * @max_transform_hierarchy_depth_intra: specifies the maximum hierarchy
> + *					 depth for transform units of
> + *					 coding units coded in intra
> + *					 prediction mode
> + * @pcm_sample_bit_depth_luma_minus1: specifies the number of bits used to
> + *				      represent each of PCM sample values of the
> + *				      luma component
> + * @pcm_sample_bit_depth_chroma_minus1: specifies the number of bits used to
> + *					represent each of PCM sample values of
> + *					the chroma components
> + * @log2_min_pcm_luma_coding_block_size_minus3: plus 3 specifies the minimum size
> + *						of coding blocks
> + * @log2_diff_max_min_pcm_luma_coding_block_size: specifies the difference between
> + *						  the maximum and minimum size of
> + *						  coding blocks
> + * @num_short_term_ref_pic_sets: specifies the number of st_ref_pic_set()
> + *				 syntax structures included in the SPS
> + * @num_long_term_ref_pics_sps:	specifies the number of candidate long-term
> + *				reference pictures that are specified in the SPS
> + * @chroma_format_idc: specifies the chroma sampling
> + * @sps_max_sub_layers_minus1: plus 1 specifies the maximum number of temporal
> + *			       sub-layers
> + * @flags: see V4L2_HEVC_SPS_FLAG_{}
> + */
>  struct v4l2_ctrl_hevc_sps {
> -	/* ISO/IEC 23008-2, ITU-T Rec. H.265: Sequence parameter set */
>  	__u8	video_parameter_set_id;
>  	__u8	seq_parameter_set_id;
>  	__u16	pic_width_in_luma_samples;
> @@ -108,8 +167,43 @@ struct v4l2_ctrl_hevc_sps {
>  #define V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT	(1ULL << 19)
>  #define V4L2_HEVC_PPS_FLAG_UNIFORM_SPACING			(1ULL << 20)
>  
> +/**
> + * struct v4l2_ctrl_hevc_pps - ITU-T Rec. H.265: Picture parameter set
> + *
> + * @pic_parameter_set_id: identifies the PPS for reference by other
> + *			  syntax elements
> + * @num_extra_slice_header_bits: specifies the number of extra slice header
> + *				 bits that are present in the slice header RBSP
> + *				 for coded pictures referring to the PPS.
> + * @num_ref_idx_l0_default_active_minus1: specifies the inferred value of
> + *					  num_ref_idx_l0_active_minus1
> + * @num_ref_idx_l1_default_active_minus1: specifies the inferred value of
> + *					  num_ref_idx_l1_active_minus1
> + * @init_qp_minus26: plus 26 specifies the initial value of SliceQp Y for
> + *		     each slice referring to the PPS
> + * @diff_cu_qp_delta_depth: specifies the difference between the luma coding
> + *			    tree block size and the minimum luma coding block
> + *			    size of coding units that convey cu_qp_delta_abs
> + *			    and cu_qp_delta_sign_flag
> + * @pps_cb_qp_offset: specify the offsets to the luma quantization parameter Cb
> + * @pps_cr_qp_offset: specify the offsets to the luma quantization parameter Cr
> + * @num_tile_columns_minus1: plus 1 specifies the number of tile columns
> + *			     partitioning the picture
> + * @num_tile_rows_minus1: plus 1 specifies the number of tile rows partitioning
> + *			  the picture
> + * @column_width_minus1: plus 1 specifies the width of the i-th tile column in

"the i-th" -> each

I think that's easier to understand.

> + *			 units of coding tree blocks
> + * @row_height_minus1: plus 1 specifies the height of the i-th tile row in

Ditto.

> + *		       units of coding tree blocks
> + * @pps_beta_offset_div2: specify the default deblocking parameter offsets for
> + *			  beta divided by 2
> + * @pps_tc_offset_div2: specify the default deblocking parameter offsets for tC
> + *			divided by 2
> + * @log2_parallel_merge_level_minus2: plus 2 specifies the value of the variable
> + *				      Log2ParMrgLevel
> + * @flags: see V4L2_HEVC_PPS_FLAG_{}
> + */
>  struct v4l2_ctrl_hevc_pps {
> -	/* ISO/IEC 23008-2, ITU-T Rec. H.265: Picture parameter set */
>  	__u8	pic_parameter_set_id;
>  	__u8	num_extra_slice_header_bits;
>  	__u8	num_ref_idx_l0_default_active_minus1;
> @@ -148,6 +242,14 @@ struct v4l2_ctrl_hevc_pps {
>  
>  #define V4L2_HEVC_DPB_ENTRIES_NUM_MAX		16
>  
> +/**
> + * struct v4l2_hevc_dpb_entry - HEVC decoded picture buffer entry
> + *
> + * @timestamp: timestamp of the V4L2 capture buffer to use as reference.
> + * @flags: long term flag for the reference frame
> + * @field_pic: whether the reference is a field picture or a frame.
> + * @pic_order_cnt_val: the picture order count of the reference.
> + */
>  struct v4l2_hevc_dpb_entry {
>  	__u64	timestamp;
>  	__u8	flags;
> @@ -156,6 +258,31 @@ struct v4l2_hevc_dpb_entry {
>  	__u8	padding[2];
>  };
>  
> +/**
> + * struct v4l2_hevc_pred_weight_table - HEVC weighted prediction parameters
> + *
> + * @delta_luma_weight_l0: the difference of the weighting factor applied
> + *			  to the luma prediction value for list 0
> + * @luma_offset_l0: the additive offset applied to the luma prediction value
> + *		    for list 0
> + * @delta_chroma_weight_l0: the difference of the weighting factor applied
> + *			    to the chroma prediction values for list 0
> + * @chroma_offset_l0: the difference of the additive offset applied to
> + *		      the chroma prediction values for list 0
> + * @delta_luma_weight_l1: the difference of the weighting factor applied
> + *			  to the luma prediction value for list 1
> + * @luma_offset_l1: the additive offset applied to the luma prediction value
> + *		    for list 1
> + * @delta_chroma_weight_l1: the difference of the weighting factor applied
> + *			    to the chroma prediction values for list 1
> + * @chroma_offset_l1: the difference of the additive offset applied to
> + *		      the chroma prediction values for list 1
> + * @luma_log2_weight_denom: the base 2 logarithm of the denominator for
> + *			    all luma weighting factors
> + * @delta_chroma_log2_weight_denom: the difference of the base 2 logarithm
> + *				    of the denominator for all chroma
> + *				    weighting factors
> + */
>  struct v4l2_hevc_pred_weight_table {
>  	__s8	delta_luma_weight_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX];
>  	__s8	luma_offset_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX];
> @@ -184,6 +311,50 @@ struct v4l2_hevc_pred_weight_table {
>  #define V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_LOOP_FILTER_ACROSS_SLICES_ENABLED (1ULL << 8)
>  #define V4L2_HEVC_SLICE_PARAMS_FLAG_DEPENDENT_SLICE_SEGMENT	(1ULL << 9)
>  
> +/**
> + * v4l2_ctrl_hevc_slice_params - HEVC slice parameters
> + *
> + * @bit_size: size (in bits) of the current slice data
> + * @data_bit_offset: offset (in bits) to the video data in the current slice data
> + * @nal_unit_type: specifies the coding type of the slice (B, P or I)
> + * @nuh_temporal_id_plus1: minus 1 specifies a temporal identifier for the NAL unit
> + * @slice_type: see V4L2_HEVC_SLICE_TYPE_{}
> + * @colour_plane_id: specifies the colour plane associated with the current slice
> + * @slice_pic_order_cnt: specifies the picture order count
> + * @num_ref_idx_l0_active_minus1: specifies the maximum reference index for
> + *				  reference picture list 0 that may be used to decode
> + *				  the slice
> + * @num_ref_idx_l1_active_minus1: specifies the maximum reference index for
> + *				  reference picture list 1 that may be used to decode
> + *				  the slice
> + * @collocated_ref_idx: specifies the reference index of the collocated picture used
> + *			for temporal motion vector prediction
> + * @five_minus_max_num_merge_cand: specifies the maximum number of merging
> + *				   motion vector prediction candidates supported in
> + *				   the slice subtracted from 5
> + * @slice_qp_delta: specifies the initial value of QpY to be used for the coding
> + *		    blocks in the slice
> + * @slice_cb_qp_offset: specifies a difference to be added to the value of pps_cb_qp_offset
> + * @slice_cr_qp_offset: specifies a difference to be added to the value of pps_cr_qp_offset
> + * @slice_act_y_qp_offset: screen content extension parameters
> + * @slice_act_cb_qp_offset: screen content extension parameters
> + * @slice_act_cr_qp_offset: screen content extension parameters
> + * @slice_beta_offset_div2: specify the deblocking parameter offsets for beta divided by 2
> + * @slice_tc_offset_div2: specify the deblocking parameter offsets for tC divided by 2
> + * @pic_struct: indicates whether a picture should be displayed as a frame or as one or
> + *		more fields
> + * @slice_segment_addr: specifies the address of the first coding tree block in
> + *			the slice segment
> + * @ref_idx_l0: the list of L0 reference elements as indices in the DPB
> + * @ref_idx_l1: the list of L1 reference elements as indices in the DPB
> + * @short_term_ref_pic_set_size: specifies the size of short-term reference
> + *				 pictures included in the SPS
> + * @long_term_ref_pic_set_size: specifies the size of long-term reference
> + *				picture include in the SPS
> + * @pred_weight_table: the prediction weight coefficients for inter-picture
> + *		       prediction
> + * @flags: see V4L2_HEVC_SLICE_PARAMS_FLAG_{}
> + */
>  struct v4l2_ctrl_hevc_slice_params {
>  	__u32	bit_size;
>  	__u32	data_bit_offset;
> @@ -230,6 +401,28 @@ struct v4l2_ctrl_hevc_slice_params {
>  #define V4L2_HEVC_DECODE_PARAM_FLAG_IDR_PIC		0x2
>  #define V4L2_HEVC_DECODE_PARAM_FLAG_NO_OUTPUT_OF_PRIOR  0x4
>  
> +/**
> + * struct v4l2_ctrl_hevc_decode_params - HEVC decode parameters
> + *
> + * @pic_order_cnt_val: picture order count
> + * @short_term_ref_pic_set_size: specifies the size of short-term reference
> + *				 pictures set included in the SPS of the first slice
> + * @long_term_ref_pic_set_size: specifies the size of long-term reference
> + *				pictures set include in the SPS of the first slice
> + * @num_active_dpb_entries: the number of entries in dpb
> + * @dpb: the decoded picture buffer, for meta-data about reference frames
> + * @num_poc_st_curr_before: the number of reference pictures in the short-term
> + *			    set that come before the current frame
> + * @num_poc_st_curr_after: the number of reference pictures in the short-term
> + *			   set that come after the current frame
> + * @num_poc_lt_curr: the number of reference pictures in the long-term set
> + * @poc_st_curr_before: provides the index of the short term before references
> + *			in DPB array
> + * @poc_st_curr_after: provides the index of the short term after references
> + *		       in DPB array
> + * @poc_lt_curr: provides the index of the long term references in DPB array
> + * @flags: see V4L2_HEVC_DECODE_PARAM_FLAG_{}
> + */
>  struct v4l2_ctrl_hevc_decode_params {
>  	__s32	pic_order_cnt_val;
>  	__u16	short_term_ref_pic_set_size;
> @@ -245,6 +438,28 @@ struct v4l2_ctrl_hevc_decode_params {
>  	__u64	flags;
>  };
>  
> +/**
> + * struct v4l2_ctrl_hevc_scaling_matrix - HEVC scaling lists parameters
> + *
> + * @scaling_list_4x4: scaling list is used for the scaling process for
> + *		      transform coefficients. The values on each scaling
> + *		      list are expected in raster scan order
> + * @scaling_list_8x8: scaling list is used for the scaling process for
> + *		      transform coefficients. The values on each scaling
> + *		      list are expected in raster scan order
> + * @scaling_list_16x16: scaling list is used for the scaling process for
> + *			transform coefficients. The values on each scaling
> + *			list are expected in raster scan order
> + * @scaling_list_32x32:	scaling list is used for the scaling process for
> + *			transform coefficients. The values on each scaling
> + *			list are expected in raster scan order
> + * @scaling_list_dc_coef_16x16: scaling list is used for the scaling process
> + *				for transform coefficients. The values on each
> + *				scaling list are expected in raster scan order.
> + * @scaling_list_dc_coef_32x32:	scaling list is used for the scaling process
> + *				for transform coefficients. The values on each
> + *				scaling list are expected in raster scan order.
> + */
>  struct v4l2_ctrl_hevc_scaling_matrix {
>  	__u8	scaling_list_4x4[6][16];
>  	__u8	scaling_list_8x8[6][64];

Regards,

	Hans