| Message ID | 20210505122347.7576-4-andrzej.p@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix .buf_prepare | expand |
diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c b/drivers/staging/media/sunxi/cedrus/cedrus_video.c index b62eb8e84057..bf731caf2ed5 100644 --- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c +++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c @@ -457,7 +457,13 @@ static int cedrus_buf_prepare(struct vb2_buffer *vb) if (vb2_plane_size(vb, 0) < pix_fmt->sizeimage) return -EINVAL; - vb2_set_plane_payload(vb, 0, pix_fmt->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, pix_fmt->sizeimage); return 0; }
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 cedrus_h264.c or cedrus_vp8.c. Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com> --- drivers/staging/media/sunxi/cedrus/cedrus_video.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)