As per spec, the field refslist requires interleaving top and bottom field in a specific way that does not fit inside the sort operation. Reorder in-place the references so that their parity sart with the same parity as the current picture and do that for both short and longterm references separately. Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx> --- drivers/media/v4l2-core/v4l2-h264.c | 45 +++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c index c3fad382882d..2f7ee8d5479f 100644 --- a/drivers/media/v4l2-core/v4l2-h264.c +++ b/drivers/media/v4l2-core/v4l2-h264.c @@ -243,6 +243,43 @@ static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb, return poca < pocb ? -1 : 1; } +/* + * The references need to be reorder so that reference are alternating between + * top and bottom ref starting with the current picture parity. This have to be + * done for short term and long term references separately. + */ +static void reorder_field_reflist(const struct v4l2_h264_reflist_builder *b, + struct v4l2_h264_reference *reflist) +{ + struct v4l2_h264_reference tmplist[V4L2_H264_REF_LIST_LEN]; + u8 lt, i = 0, j = 0, k = 0; + + memcpy(tmplist, reflist, sizeof(tmplist[0]) * b->num_valid); + + for (lt = 0; lt <= 1; lt++) { + do { + for (; i < b->num_valid && b->refs[tmplist[i].index].longterm == lt; i++) { + if (tmplist[i].fields == b->cur_pic_fields) { + reflist[k] = tmplist[i]; + k++; + i++; + break; + } + } + + for (; j < b->num_valid && b->refs[tmplist[j].index].longterm == lt; j++) { + if (tmplist[j].fields != b->cur_pic_fields) { + reflist[k] = tmplist[j]; + k++; + j++; + break; + } + } + } while ((i < b->num_valid && b->refs[tmplist[i].index].longterm == lt) || + (j < b->num_valid && b->refs[tmplist[j].index].longterm == lt)); + } +} + static char ref_type_to_char (u8 ref_type) { switch (ref_type) { @@ -345,6 +382,9 @@ v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder, sort_r(reflist, builder->num_valid, sizeof(*reflist), v4l2_h264_p_ref_list_cmp, NULL, builder); + if (builder->cur_pic_fields != V4L2_H264_FRAME_REF) + reorder_field_reflist(builder, reflist); + print_ref_list_p(builder, reflist); } EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list); @@ -378,6 +418,11 @@ v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder, sort_r(b1_reflist, builder->num_valid, sizeof(*b1_reflist), v4l2_h264_b1_ref_list_cmp, NULL, builder); + if (builder->cur_pic_fields != V4L2_H264_FRAME_REF) { + reorder_field_reflist(builder, b0_reflist); + reorder_field_reflist(builder, b1_reflist); + } + if (builder->num_valid > 1 && !memcmp(b1_reflist, b0_reflist, builder->num_valid)) swap(b1_reflist[0], b1_reflist[1]); -- 2.34.1