v4l_queue_export_bufs uses the v4l_fd type when calling EXPBUF ioctl. However, this doesn't work on mem2mem where there are one capture queue and one output queue associated to the device. The current code calls v4l_queue_export_bufs with the wrong type, failing as: fail: v4l2-test-buffers.cpp(544): q_.export_bufs(node) test VIDIOC_EXPBUF: FAIL Fix this by using the queue type instead. Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx> --- utils/common/v4l-helpers.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/utils/common/v4l-helpers.h b/utils/common/v4l-helpers.h index 83d8d7d9c073..d6866f04e23a 100644 --- a/utils/common/v4l-helpers.h +++ b/utils/common/v4l-helpers.h @@ -1633,7 +1633,7 @@ static inline int v4l_queue_export_bufs(struct v4l_fd *f, struct v4l_queue *q, unsigned b, p; int ret = 0; - expbuf.type = exp_type ? : f->type; + expbuf.type = exp_type ? : q->type; expbuf.flags = O_RDWR; memset(expbuf.reserved, 0, sizeof(expbuf.reserved)); for (b = 0; b < v4l_queue_g_buffers(q); b++) { -- 2.18.0.rc2