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Date:   Mon, 4 Apr 2022 18:36:13 +0200
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Subject: Re: [PATCH v4 06/15] media: uapi: HEVC: Add document uAPI structure
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To:     Nicolas Dufresne <nicolas@ndufresne.ca>, 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, jonas@kwiboo.se
Cc:     linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-staging@lists.linux.dev,
        linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev,
        kernel@collabora.com, knaerzche@gmail.com, jc@kynesim.co.uk
References: <20220228140838.622021-1-benjamin.gaignard@collabora.com>
 <20220228140838.622021-7-benjamin.gaignard@collabora.com>
 <9fc8c5e8aefdfdefebd9f1d389d0892c361d9b3f.camel@ndufresne.ca>
From:   Benjamin Gaignard <benjamin.gaignard@collabora.com>
In-Reply-To: <9fc8c5e8aefdfdefebd9f1d389d0892c361d9b3f.camel@ndufresne.ca>
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Le 04/04/2022 à 18:20, Nicolas Dufresne a écrit :
> Le lundi 28 février 2022 à 15:08 +0100, Benjamin Gaignard a écrit :
>> Add kernel-doc documentation for all the HEVC structures.
>>
>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
>> ---
>> Version 4:
>> - Fix space/tab issue in kernel-doc
>>
>>   .../media/v4l/ext-ctrls-codec.rst             | 156 +++++++------
>>   include/media/hevc-ctrls.h                    | 217 +++++++++++++++++-
>>   2 files changed, 304 insertions(+), 69 deletions(-)
>>
>> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>> index acf49420e56d..ac13a3eb85c2 100644
>> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>> @@ -2673,70 +2673,76 @@ 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.
>>       * - __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
>> +        the CVS
>>       * - __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.
>>       * - __u64
>>         - ``flags``
>>         - See :ref:`Sequence Parameter Set Flags <hevc_sps_flags>`
>> @@ -2815,7 +2821,8 @@ 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
>> @@ -2824,37 +2831,42 @@ 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
>> +        coding tree blocks.
>>       * - __u8
>>         - ``row_height_minus1[22]``
>> -      -
>> +      - Plus 1 specifies the height of the i-th tile row in units of coding
>> +        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.
>>       * - __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.
>> @@ -2976,10 +2988,10 @@ 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``
>>         -
>> @@ -2987,52 +2999,56 @@ 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.
>>       * - __u16
>>         - ``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.
>>       * - __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.
>> @@ -3222,36 +3238,44 @@ 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 b3540167df9e..149384ca4c84 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]
>> + * @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: speciefies 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
>> + *			 units of coding tree blocks
>> + * @row_height_minus1: plus 1 specifies the height of the i-th tile row in
>> + *		       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;
>> @@ -134,6 +228,14 @@ 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: the picture order count of the reference.
> Unless I missed that change, there is two POC (its an array), but the doc does
> not reflect this.
>
>    __u16   pic_order_cnt[2];
>
> In H.264, this has been split in two:
>
>          __s32 top_field_order_cnt;
>          __s32 bottom_field_order_cnt;
>
> I'm also noticing the difference in number of bits. HEVC could have been
> different, but the spec says:
>
>     The value of PicOrderCntVal shall be in the range of −2^31 to 2^31 − 1,
>     inclusive
>     
> Clarification needed if this isn't meant to be PicOrderCntVal but
> pic_order_cnt_lsb. That being said, it looks like DXVA exposes that as a signed
> integer (32 bit).

I will change __u16   pic_order_cnt[2] to __s32 PicOrderCntVal
to follow the spec naming that will be more clear like that.

Thanks,
Benjamin

>
>> + */
>>   struct v4l2_hevc_dpb_entry {
>>   	__u64	timestamp;
>>   	__u8	flags;
>> @@ -142,6 +244,31 @@ 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];
>> @@ -170,6 +297,50 @@ 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 number of st_ref_pic_set()
>> + *				 syntax structures included in the SPS
>> + * @long_term_ref_pic_set_size: specifies the number of candidate long-term
>> + *				reference pictures that are specified 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;
>> @@ -216,6 +387,24 @@ 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
>> + * @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;
>>   	__u8	num_active_dpb_entries;
>> @@ -229,6 +418,28 @@ 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];
>
> Looks good otherwise.
>
> Nicolas
>
>