Hi Gustavo,
On Thu, Aug 31, 2017 at 10:50:35PM -0300, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
>
> Implement the needed pieces to let userspace subscribe for
> V4L2_EVENT_BUF_QUEUED events. Videobuf2 will queue the event for the
> DQEVENT ioctl.
>
> v3: - Do not call v4l2 event API from vb2 (Mauro)
>
> v2: - Use VIDEO_MAX_FRAME to allocate room for events at
> v4l2_event_subscribe() (Hans)
>
> Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-ctrls.c | 6 +++++-
> drivers/media/v4l2-core/videobuf2-core.c | 2 ++
> drivers/media/v4l2-core/videobuf2-v4l2.c | 13 +++++++++++++
> 3 files changed, 20 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
> index dd1db678718c..17d4b9e3eec6 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> @@ -3438,8 +3438,12 @@ EXPORT_SYMBOL(v4l2_ctrl_log_status);
> int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
> const struct v4l2_event_subscription *sub)
> {
> - if (sub->type == V4L2_EVENT_CTRL)
> + switch (sub->type) {
> + case V4L2_EVENT_CTRL:
> return v4l2_event_subscribe(fh, sub, 0, &v4l2_ctrl_sub_ev_ops);
> + case V4L2_EVENT_BUF_QUEUED:
> + return v4l2_event_subscribe(fh, sub, VIDEO_MAX_FRAME, NULL);
While I think this is probably the correct place to add the event
subscription handling, the name of the function no longer corresponds what
it does, nor it belongs to v4l2-ctrls.c.
v4l2_ctrl_subscribe_event() is also used for subscribing control events on
sub-devices. BUF_QUEUED events will be available only on video nodes.
BUF_QUEUED events presumably should be availble on all video nodes that
support V4L2_CAP_STREAMING capability. Perhaps this could be handled by
moving v4l2_ctrl_subscribe_event() to v4l2-event.c and renaming it e.g.
v4l2_event_subscribe_v4l2(), for these events originate from specific
conditions the V4L2 framework is aware of.
v4l2_ctrl_subdev_subscribe_event() handling needs to be addressed as well.
A separate patch would be nice.
> + }
> return -EINVAL;
> }
> EXPORT_SYMBOL(v4l2_ctrl_subscribe_event);
> diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
> index b19c1bc4b083..bbbae0eed567 100644
> --- a/drivers/media/v4l2-core/videobuf2-core.c
> +++ b/drivers/media/v4l2-core/videobuf2-core.c
> @@ -1231,6 +1231,8 @@ static void __enqueue_in_driver(struct vb2_buffer *vb)
> trace_vb2_buf_queue(q, vb);
>
> call_void_vb_qop(vb, buf_queue, vb);
> +
> + call_void_bufop(q, buffer_queued, vb);
> }
>
> static int __buf_prepare(struct vb2_buffer *vb, const void *pb)
> diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c b/drivers/media/v4l2-core/videobuf2-v4l2.c
> index 8c322cd1b346..1c93bfedaffc 100644
> --- a/drivers/media/v4l2-core/videobuf2-v4l2.c
> +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c
> @@ -138,6 +138,18 @@ static void __copy_timestamp(struct vb2_buffer *vb, const void *pb)
> }
> };
>
> +static void __buffer_queued(struct vb2_buffer *vb)
> +{
> + struct video_device *vdev = to_video_device(vb->vb2_queue->dev);
> + struct v4l2_event event;
> +
> + memset(&event, 0, sizeof(event));
> + event.type = V4L2_EVENT_BUF_QUEUED;
> + event.u.buf_queued.index = vb->index;
> +
> + v4l2_event_queue(vdev, &event);
> +}
> +
> static void vb2_warn_zero_bytesused(struct vb2_buffer *vb)
> {
> static bool check_once;
> @@ -455,6 +467,7 @@ static const struct vb2_buf_ops v4l2_buf_ops = {
> .fill_user_buffer = __fill_v4l2_buffer,
> .fill_vb2_buffer = __fill_vb2_buffer,
> .copy_timestamp = __copy_timestamp,
> + .buffer_queued = __buffer_queued,
> };
>
> /**
--
Kind regards,
Sakari Ailus
e-mail: sakari.ailus@xxxxxx
