[RFCv4 PATCH 5/6] videobuf2-core: also test for pending events.

From: Hans Verkuil
Date: Thu Sep 29 2011 - 03:45:17 EST


From: Hans Verkuil <hans.verkuil@xxxxxxxxx>

Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
---
drivers/media/video/videobuf2-core.c | 41 +++++++++++++++++++++++----------
1 files changed, 28 insertions(+), 13 deletions(-)

diff --git a/drivers/media/video/videobuf2-core.c b/drivers/media/video/videobuf2-core.c
index a921638..7674220 100644
--- a/drivers/media/video/videobuf2-core.c
+++ b/drivers/media/video/videobuf2-core.c
@@ -19,6 +19,9 @@
#include <linux/slab.h>
#include <linux/sched.h>

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

static int debug;
@@ -1363,15 +1366,28 @@ static int __vb2_cleanup_fileio(struct vb2_queue *q);
* For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
* will be reported as available for writing.
*
+ * If the driver uses struct v4l2_fh, then vb2_poll() will also check for any
+ * pending events.
+ *
* The return values from this function are intended to be directly returned
* from poll handler in driver.
*/
unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
{
+ struct video_device *vfd = video_devdata(file);
unsigned long req_events = poll_requested_events(wait);
- unsigned long flags;
- unsigned int ret;
struct vb2_buffer *vb = NULL;
+ unsigned int res = 0;
+ unsigned long flags;
+
+ if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
+ struct v4l2_fh *fh = file->private_data;
+
+ if (v4l2_event_pending(fh))
+ res = POLLPRI;
+ else if (req_events & POLLPRI)
+ poll_wait(file, &fh->wait, wait);
+ }

/*
* Start file I/O emulator only if streaming API has not been used yet.
@@ -1379,19 +1395,17 @@ unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
if (q->num_buffers == 0 && q->fileio == NULL) {
if (!V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_READ) &&
(req_events & (POLLIN | POLLRDNORM))) {
- ret = __vb2_init_fileio(q, 1);
- if (ret)
- return POLLERR;
+ if (__vb2_init_fileio(q, 1))
+ return res | POLLERR;
}
if (V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_WRITE) &&
(req_events & (POLLOUT | POLLWRNORM))) {
- ret = __vb2_init_fileio(q, 0);
- if (ret)
- return POLLERR;
+ if (__vb2_init_fileio(q, 0))
+ return res | POLLERR;
/*
* Write to OUTPUT queue can be done immediately.
*/
- return POLLOUT | POLLWRNORM;
+ return res | POLLOUT | POLLWRNORM;
}
}

@@ -1399,7 +1413,7 @@ unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
* There is nothing to wait for if no buffers have already been queued.
*/
if (list_empty(&q->queued_list))
- return POLLERR;
+ return res | POLLERR;

poll_wait(file, &q->done_wq, wait);

@@ -1414,10 +1428,11 @@ unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)

if (vb && (vb->state == VB2_BUF_STATE_DONE
|| vb->state == VB2_BUF_STATE_ERROR)) {
- return (V4L2_TYPE_IS_OUTPUT(q->type)) ? POLLOUT | POLLWRNORM :
- POLLIN | POLLRDNORM;
+ return (V4L2_TYPE_IS_OUTPUT(q->type)) ?
+ res | POLLOUT | POLLWRNORM :
+ res | POLLIN | POLLRDNORM;
}
- return 0;
+ return res;
}
EXPORT_SYMBOL_GPL(vb2_poll);

--
1.7.5.4

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