diff --git a/include/media/h264-ctrls.h b/include/media/h264-ctrls.h
index ec4799154438..afc8e7c05c18 100644
--- a/include/media/h264-ctrls.h
+++ b/include/media/h264-ctrls.h
@@ -46,11 +46,38 @@
 #define V4L2_CTRL_TYPE_H264_DECODE_PARAMS	0x0114
 #define V4L2_CTRL_TYPE_H264_PRED_WEIGHTS	0x0115
 
+/**
+ * enum v4l2_mpeg_video_h264_decode_mode - Decoding mode
+ *
+ * @V4L2_MPEG_VIDEO_H264_DECODE_MODE_SLICE_BASED: indicates that decoding
+ * is performed one slice at a time. In this mode,
+ * V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS must contain the parsed slice
+ * parameters and the OUTPUT buffer must contain a single slice.
+ * V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF feature is used
+ * in order to support multislice frames.
+ * @V4L2_MPEG_VIDEO_H264_DECODE_MODE_FRAME_BASED: indicates that
+ * decoding is performed per frame. The OUTPUT buffer must contain
+ * all slices and also both fields. This mode is typically supported
+ * by device drivers that are able to parse the slice(s) header(s)
+ * in hardware. When this mode is selected,
+ * V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS is not used.
+ */
 enum v4l2_mpeg_video_h264_decode_mode {
 	V4L2_MPEG_VIDEO_H264_DECODE_MODE_SLICE_BASED,
 	V4L2_MPEG_VIDEO_H264_DECODE_MODE_FRAME_BASED,
 };
 
+/**
+ * enum v4l2_mpeg_video_h264_start_code - Start code
+ *
+ * @V4L2_MPEG_VIDEO_H264_START_CODE_NONE: slices are passed
+ * to the driver without any start code.
+ * @V4L2_MPEG_VIDEO_H264_START_CODE_ANNEX_B: slices are passed
+ * to the driver with an Annex B start code prefix
+ * (legal start codes can be 3-bytes 0x000001 or 4-bytes 0x00000001).
+ * This mode is typically supported by device drivers that parse
+ * the start code in hardware.
+ */
 enum v4l2_mpeg_video_h264_start_code {
 	V4L2_MPEG_VIDEO_H264_START_CODE_NONE,
 	V4L2_MPEG_VIDEO_H264_START_CODE_ANNEX_B,
@@ -71,6 +98,12 @@ enum v4l2_mpeg_video_h264_start_code {
 #define V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD		0x20
 #define V4L2_H264_SPS_FLAG_DIRECT_8X8_INFERENCE			0x40
 
+/**
+ * struct v4l2_ctrl_h264_sps - H264 sequence parameter set
+ *
+ * All the members on this sequence parameter set structure match the
+ * sequence parameter set syntax as specified by the H264 specification.
+ */
 struct v4l2_ctrl_h264_sps {
 	__u8 profile_idc;
 	__u8 constraint_set_flags;
@@ -101,6 +134,20 @@ struct v4l2_ctrl_h264_sps {
 #define V4L2_H264_PPS_FLAG_TRANSFORM_8X8_MODE				0x0040
 #define V4L2_H264_PPS_FLAG_SCALING_MATRIX_PRESENT			0x0080
 
+/**
+ * struct v4l2_ctrl_h264_pps - H264 picture parameter set
+ *
+ * Except where noted, all the members on this picture parameter set
+ * structure match the sequence parameter set syntax as specified
+ * by the H264 specification.
+ *
+ * In particular, V4L2_H264_PPS_FLAG_SCALING_MATRIX_PRESENT flag
+ * has a specific meaning. This flag should be set if a non-flat
+ * scaling matrix applies to the picture. In this case, applications
+ * are expected to use V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX.
+ * This will be the case if SPS scaling_matrix_present_flag or
+ * PPS pic_scaling_matrix_present_flag syntax elements are set.
+ */
 struct v4l2_ctrl_h264_pps {
 	__u8 pic_parameter_set_id;
 	__u8 seq_parameter_set_id;
@@ -115,6 +162,18 @@ struct v4l2_ctrl_h264_pps {
 	__u16 flags;
 };
 
+/**
+ * struct v4l2_ctrl_h264_scaling_matrix - H264 scaling matrices
+ *
+ * @scaling_list_4x4: scaling matrix after applying the inverse
+ * scanning process. Expected list order is Intra Y, Intra Cb,
+ * Intra Cr, Inter Y, Inter Cb, Inter Cr. The values on each
+ * scaling list are expected in raster scan order.
+ * @scaling_list_8x8: scaling matrix after applying the inverse
+ * scanning process. Expected list order is Intra Y, Inter Y,
+ * Intra Cb, Inter Cb, Intra Cr, Inter Cr. The values on each
+ * scaling list are expected in raster scan order.
+ */
 struct v4l2_ctrl_h264_scaling_matrix {
 	__u8 scaling_list_4x4[6][16];
 	__u8 scaling_list_8x8[6][64];
@@ -134,6 +193,12 @@ struct v4l2_h264_weight_factors {
 	 ((pps)->weighted_bipred_idc == 1 && \
 	  (slice)->slice_type == V4L2_H264_SLICE_TYPE_B))
 
+/**
+ * struct v4l2_ctrl_h264_pred_weights - Prediction weight table
+ *
+ * Prediction weight table, which matches the syntax specified
+ * by the H264 specification.
+ */
 struct v4l2_ctrl_h264_pred_weights {
 	__u16 luma_log2_weight_denom;
 	__u16 chroma_log2_weight_denom;
@@ -153,19 +218,41 @@ struct v4l2_ctrl_h264_pred_weights {
 #define V4L2_H264_BOTTOM_FIELD_REF			0x2
 #define V4L2_H264_FRAME_REF				0x3
 
+/**
+ * struct v4l2_h264_reference - H264 picture reference
+ *
+ * @fields: indicates how the picture is referenced.
+ * Valid values are V4L2_H264_{}_REF.
+ * @index: index into v4l2_ctrl_h264_decode_params.dpb[].
+ */
 struct v4l2_h264_reference {
 	__u8 fields;
-
-	/* Index into v4l2_ctrl_h264_decode_params.dpb[] */
 	__u8 index;
 };
 
+/**
+ * struct v4l2_ctrl_h264_slice_params - H264 slice parameters
+ *
+ * This structure holds the H264 syntax elements that are specified
+ * as non-invariant for the slices in a given frame.
+ *
+ * Slice invariant syntax elements are contained in struct
+ * v4l2_ctrl_h264_decode_params. This is done to reduce the API surface
+ * on frame-based decoders, where slice header parsing is done by the
+ * hardware.
+ *
+ * Slice invariant syntax elements are specified in specification section
+ * "7.4.3 Slice header semantics".
+ *
+ * Except where noted, the members on this struct match the slice header syntax.
+ *
+ * @header_bit_size: offset in bits to slice_data() from the beginning of this slice.
+ * @ref_pic_list0: reference picture list 0 after applying the per-slice modifications.
+ * @ref_pic_list1: reference picture list 1 after applying the per-slice modifications.
+ */
 struct v4l2_ctrl_h264_slice_params {
-	/* Offset in bits to slice_data() from the beginning of this slice. */
 	__u32 header_bit_size;
-
 	__u32 first_mb_in_slice;
-
 	__u8 slice_type;
 	__u8 colour_plane_id;
 	__u8 redundant_pic_cnt;
@@ -191,22 +278,55 @@ struct v4l2_ctrl_h264_slice_params {
 #define V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM	0x04
 #define V4L2_H264_DPB_ENTRY_FLAG_FIELD		0x08
 
+/**
+ * struct v4l2_h264_dpb_entry - H264 decoded picture buffer entry
+ *
+ * @reference_ts: timestamp of the V4L2 capture buffer to use as reference.
+ * The timestamp refers to the timestamp field in struct v4l2_buffer.
+ * Use v4l2_timeval_to_ns() to convert the struct timeval to a __u64.
+ * @pic_num: matches PicNum variable assigned during the reference
+ * picture lists construction process.
+ * @frame_num: frame identifier which matches frame_num syntax element.
+ * @fields: indicates how the DPB entry is referenced. Valid values are
+ * V4L2_H264_{}_REF.
+ * @top_field_order_cnt: matches TopFieldOrderCnt picture value.
+ * @bottom_field_order_cnt: matches BottomFieldOrderCnt picture value.
+ * Note that picture field is indicated by v4l2_buffer.field.
+ */
 struct v4l2_h264_dpb_entry {
 	__u64 reference_ts;
 	__u32 pic_num;
 	__u16 frame_num;
 	__u8 fields;
 	__u8 reserved[5];
-	/* Note that field is indicated by v4l2_buffer.field */
 	__s32 top_field_order_cnt;
 	__s32 bottom_field_order_cnt;
-	__u32 flags; /* V4L2_H264_DPB_ENTRY_FLAG_* */
+	__u32 flags;
 };
 
 #define V4L2_H264_DECODE_PARAM_FLAG_IDR_PIC		0x01
 #define V4L2_H264_DECODE_PARAM_FLAG_FIELD_PIC		0x02
 #define V4L2_H264_DECODE_PARAM_FLAG_BOTTOM_FIELD	0x04
 
+/**
+ * struct v4l2_ctrl_h264_decode_params - H264 decoding parameters
+ *
+ * @dpb: decoded picture buffer.
+ * @nal_ref_idc: slice header syntax element.
+ * @frame_num: slice header syntax element.
+ * @top_field_order_cnt: matches TopFieldOrderCnt picture value.
+ * @bottom_field_order_cnt: matches BottomFieldOrderCnt picture value.
+ * Note that picture field is indicated by v4l2_buffer.field.
+ * @idr_pic_id: slice header syntax element.
+ * @pic_order_cnt_lsb: slice header syntax element.
+ * @delta_pic_order_cnt_bottom: slice header syntax element.
+ * @delta_pic_order_cnt0: slice header syntax element.
+ * @delta_pic_order_cnt1: slice header syntax element.
+ * @dec_ref_pic_marking_bit_size: size in bits of dec_ref_pic_marking()
+ * syntax element.
+ * @pic_order_cnt_bit_size: size in bits of pic order count syntax.
+ * @slice_group_change_cycle: slice header syntax element.
+ */
 struct v4l2_ctrl_h264_decode_params {
 	struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES];
 	__u16 nal_ref_idc;
@@ -218,14 +338,12 @@ struct v4l2_ctrl_h264_decode_params {
 	__s32 delta_pic_order_cnt_bottom;
 	__s32 delta_pic_order_cnt0;
 	__s32 delta_pic_order_cnt1;
-	/* Size in bits of dec_ref_pic_marking() syntax element. */
 	__u32 dec_ref_pic_marking_bit_size;
-	/* Size in bits of pic order count syntax. */
 	__u32 pic_order_cnt_bit_size;
 	__u32 slice_group_change_cycle;
 
 	__u32 reserved;
-	__u32 flags; /* V4L2_H264_DECODE_PARAM_FLAG_* */
+	__u32 flags;
 };
 
 #endif
