From: Ezequiel Garcia ezequiel@collabora.com
[ Upstream commit ba1ed4ae760a81caf39f54232e089d95157a0dba ]
The driver should only set the payload on .buf_prepare if the buffer is CAPTURE type. If an OUTPUT buffer has a zero bytesused set by userspace then v4l2-core will set it to buffer length.
If we overwrite bytesused for OUTPUT buffers, too, then vb2_get_plane_payload() will return incorrect value which might be then written to hw registers by the driver in rkvdec-h264.c.
[Changed the comment and used V4L2_TYPE_IS_CAPTURE macro]
Fixes: cd33c830448ba ("media: rkvdec: Add the rkvdec driver") Signed-off-by: Ezequiel Garcia ezequiel@collabora.com Signed-off-by: Adrian Ratiu adrian.ratiu@collabora.com Signed-off-by: Andrzej Pietrasiewicz andrzej.p@collabora.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/staging/media/rkvdec/rkvdec.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/staging/media/rkvdec/rkvdec.c b/drivers/staging/media/rkvdec/rkvdec.c index 8c17615f3a7a..7131156c1f2c 100644 --- a/drivers/staging/media/rkvdec/rkvdec.c +++ b/drivers/staging/media/rkvdec/rkvdec.c @@ -481,7 +481,15 @@ static int rkvdec_buf_prepare(struct vb2_buffer *vb) if (vb2_plane_size(vb, i) < sizeimage) return -EINVAL; } - vb2_set_plane_payload(vb, 0, f->fmt.pix_mp.plane_fmt[0].sizeimage); + + /* + * Buffer's bytesused must be written by driver for CAPTURE buffers. + * (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, f->fmt.pix_mp.plane_fmt[0].sizeimage); + return 0; }