On 06/16/17 09:39, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.pado...@collabora.com>
>
> Receive in-fence from userspace and add support for waiting on them
> before queueing the buffer to the driver. Buffers are only queued
> to the driver once they are ready. A buffer is ready when its
> in-fence signals.
>
> v2:
> - fix vb2_queue_or_prepare_buf() ret check
> - remove check for VB2_MEMORY_DMABUF only (Javier)
> - check num of ready buffers to start streaming
> - when queueing, start from the first ready buffer
> - handle queue cancel
>
> Signed-off-by: Gustavo Padovan <gustavo.pado...@collabora.com>
> ---
> drivers/media/Kconfig | 1 +
> drivers/media/v4l2-core/videobuf2-core.c | 97
> +++++++++++++++++++++++++-------
> drivers/media/v4l2-core/videobuf2-v4l2.c | 15 ++++-
> include/media/videobuf2-core.h | 7 ++-
> 4 files changed, 99 insertions(+), 21 deletions(-)
>
<snip>
> diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c
> b/drivers/media/v4l2-core/videobuf2-v4l2.c
> index 110fb45..e6ad77f 100644
> --- a/drivers/media/v4l2-core/videobuf2-v4l2.c
> +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c
> @@ -23,6 +23,7 @@
> #include <linux/sched.h>
> #include <linux/freezer.h>
> #include <linux/kthread.h>
> +#include <linux/sync_file.h>
>
> #include <media/v4l2-dev.h>
> #include <media/v4l2-fh.h>
> @@ -560,6 +561,7 @@ EXPORT_SYMBOL_GPL(vb2_create_bufs);
>
> int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
> {
> + struct dma_fence *fence = NULL;
> int ret;
>
> if (vb2_fileio_is_active(q)) {
> @@ -568,7 +570,18 @@ int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
> }
>
> ret = vb2_queue_or_prepare_buf(q, b, "qbuf");
> - return ret ? ret : vb2_core_qbuf(q, b->index, b);
> + if (ret)
> + return ret;
> +
> + if (b->flags & V4L2_BUF_FLAG_IN_FENCE) {
> + fence = sync_file_get_fence(b->fence_fd);
> + if (!fence) {
> + dprintk(1, "failed to get in-fence from fd\n");
> + return -EINVAL;
> + }
> + }
> +
> + return ret ? ret : vb2_core_qbuf(q, b->index, b, fence);
> }
> EXPORT_SYMBOL_GPL(vb2_qbuf);
You need to adapt __fill_v4l2_buffer so it sets the IN_FENCE buffer flag
if there is a fence pending. It should also fill in fence_fd.
Regards,
Hans
