[PATCH v1 20/24] media: hantro: Enable HOLD_CAPTURE_BUF for H.264

[Nicolas Dufresne]

This is needed to optimizing field decoding. Each field will be
decoded in the same capture buffer, so to make use of the queues
we need to be able to ask the driver to keep the capture buffer.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne at collabora.com>
---
 drivers/staging/media/hantro/hantro_v4l2.c | 25 ++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/staging/media/hantro/hantro_v4l2.c b/drivers/staging/media/hantro/hantro_v4l2.c
index 67148ba346f5..50d636678ff3 100644
--- a/drivers/staging/media/hantro/hantro_v4l2.c
+++ b/drivers/staging/media/hantro/hantro_v4l2.c
@@ -409,6 +409,30 @@ hantro_update_requires_request(struct hantro_ctx *ctx, u32 fourcc)
 	}
 }
 
+static void
+hantro_update_requires_hold_capture_buf(struct hantro_ctx *ctx, u32 fourcc)
+{
+	struct vb2_queue *vq;
+
+	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx,
+			     V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE);
+
+	switch (fourcc) {
+	case V4L2_PIX_FMT_JPEG:
+	case V4L2_PIX_FMT_MPEG2_SLICE:
+	case V4L2_PIX_FMT_VP8_FRAME:
+	case V4L2_PIX_FMT_HEVC_SLICE:
+	case V4L2_PIX_FMT_VP9_FRAME:
+		vq->subsystem_flags &= ~(VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF);
+		break;
+	case V4L2_PIX_FMT_H264_SLICE:
+		vq->subsystem_flags |= VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF;
+		break;
+	default:
+		break;
+	}
+}
+
 static int hantro_set_fmt_out(struct hantro_ctx *ctx,
 			      struct v4l2_pix_format_mplane *pix_mp)
 {
@@ -472,6 +496,7 @@ static int hantro_set_fmt_out(struct hantro_ctx *ctx,
 	ctx->dst_fmt.quantization = pix_mp->quantization;
 
 	hantro_update_requires_request(ctx, pix_mp->pixelformat);
+	hantro_update_requires_hold_capture_buf(ctx, pix_mp->pixelformat);
 
 	vpu_debug(0, "OUTPUT codec mode: %d\n", ctx->vpu_src_fmt->codec_mode);
 	vpu_debug(0, "fmt - w: %d, h: %d\n",
-- 
2.34.1