media: hantro: Empty encoder capture buffers by default

The payload size for encoder capture buffers is set by the driver upon
finishing encoding each frame, based on the encoded length returned from
hardware, and whatever header and padding length used. Setting a
non-zero default serves no real purpose, and also causes issues if the
capture buffer is returned to userspace unused, confusing the
application.

Instead, always set the payload size to 0 for encoder capture buffers
when preparing them.

Fixes: 775fec69008d ("media: add Rockchip VPU JPEG encoder driver")
Fixes: 082aaecff35f ("media: hantro: Fix .buf_prepare")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

diff --git a/drivers/staging/media/hantro/hantro_v4l2.c b/drivers/staging/media/hantro/hantro_v4l2.c
index 8b8276ff7b28a9f942f0f309fb807665b08a149d..71a6279750bf7ca711c02edf03ba022b1d17dab5 100644 (file)
--- a/drivers/staging/media/hantro/hantro_v4l2.c
+++ b/drivers/staging/media/hantro/hantro_v4l2.c
@@ -768,8 +768,12 @@ static int hantro_buf_prepare(struct vb2_buffer *vb)
         * (for OUTPUT buffers, if userspace passes 0 bytesused, v4l2-core sets
         * it to buffer length).
         */
-       if (V4L2_TYPE_IS_CAPTURE(vq->type))
-               vb2_set_plane_payload(vb, 0, pix_fmt->plane_fmt[0].sizeimage);
+       if (V4L2_TYPE_IS_CAPTURE(vq->type)) {
+               if (ctx->is_encoder)
+                       vb2_set_plane_payload(vb, 0, 0);
+               else
+                       vb2_set_plane_payload(vb, 0, pix_fmt->plane_fmt[0].sizeimage);
+       }
 
        return 0;
 }