[RFC 07/10] [media] v4l: add support to BUF_QUEUED event

Gustavo Padovan
2017-03-13T19:21:03Z

From: Gustavo Padovan <gustavo.padovan@collabora.com>

Implement the needed pieces to let userspace subscribe for
V4L2_EVENT_BUF_QUEUED events. Videobuf2 will queue the event for the
DQEVENT ioctl.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
---
drivers/media/v4l2-core/v4l2-ctrls.c | 6 +++++-
drivers/media/v4l2-core/videobuf2-core.c | 15 +++++++++++++++
2 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 b9e08e3..1be554b 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -3413,8 +3413,12 @@ 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, 0, NULL);
+ }
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 e0e7109..d9cb777 100644
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -25,6 +25,7 @@
#include <linux/kthread.h>

#include <media/videobuf2-core.h>
+#include <media/v4l2-event.h>
#include <media/v4l2-mc.h>

#include <trace/events/vb2.h>
@@ -1221,6 +1222,18 @@ static int __qbuf_dmabuf(struct vb2_buffer *vb, const void *pb)
return ret;
}

+static void vb2_buffer_queued_event(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);
+}
+
/**
* __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing
*/
@@ -1239,6 +1252,8 @@ static void __enqueue_in_driver(struct vb2_buffer *vb)
call_void_memop(vb, prepare, vb->planes[plane].mem_priv);

call_void_vb_qop(vb, buf_queue, vb);
+
+ vb2_buffer_queued_event(vb);
}

static int __buf_prepare(struct vb2_buffer *vb, const void *pb)
--
2.9.3