diff options
| -rw-r--r-- | drivers/media/v4l2-core/videobuf2-core.c | 10 | ||||
| -rw-r--r-- | drivers/media/v4l2-core/videobuf2-v4l2.c | 14 | ||||
| -rw-r--r-- | include/media/videobuf2-core.h | 4 |
3 files changed, 20 insertions, 8 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index 2169544883e8..9fbcb67a9ee6 100644 --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -2298,6 +2298,16 @@ unsigned int vb2_core_poll(struct vb2_queue *q, struct file *file, return POLLERR; /* + * If this quirk is set and QBUF hasn't been called yet then + * return POLLERR as well. This only affects capture queues, output + * queues will always initialize waiting_for_buffers to false. + * This quirk is set by V4L2 for backwards compatibility reasons. + */ + if (q->quirk_poll_must_check_waiting_for_buffers && + q->waiting_for_buffers && (req_events & (POLLIN | POLLRDNORM))) + return POLLERR; + + /* * For output streams you can call write() as long as there are fewer * buffers queued than there are buffers available. */ diff --git a/drivers/media/v4l2-core/videobuf2-v4l2.c b/drivers/media/v4l2-core/videobuf2-v4l2.c index 8da7470ca364..7f366f1b0377 100644 --- a/drivers/media/v4l2-core/videobuf2-v4l2.c +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c @@ -771,6 +771,12 @@ int vb2_queue_init(struct vb2_queue *q) q->is_output = V4L2_TYPE_IS_OUTPUT(q->type); q->copy_timestamp = (q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) == V4L2_BUF_FLAG_TIMESTAMP_COPY; + /* + * For compatibility with vb1: if QBUF hasn't been called yet, then + * return POLLERR as well. This only affects capture queues, output + * queues will always initialize waiting_for_buffers to false. + */ + q->quirk_poll_must_check_waiting_for_buffers = true; return vb2_core_queue_init(q); } @@ -824,14 +830,6 @@ unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait) poll_wait(file, &fh->wait, wait); } - /* - * For compatibility with vb1: if QBUF hasn't been called yet, then - * return POLLERR as well. This only affects capture queues, output - * queues will always initialize waiting_for_buffers to false. - */ - if (q->waiting_for_buffers && (req_events & (POLLIN | POLLRDNORM))) - return POLLERR; - return res | vb2_core_poll(q, file, wait); } EXPORT_SYMBOL_GPL(vb2_poll); diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index 5342ff4d748f..88e3ab496e8f 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -404,6 +404,9 @@ struct vb2_buf_ops { * @fileio_read_once: report EOF after reading the first buffer * @fileio_write_immediately: queue buffer after each write() call * @allow_zero_bytesused: allow bytesused == 0 to be passed to the driver + * @quirk_poll_must_check_waiting_for_buffers: Return POLLERR at poll when QBUF + * has not been called. This is a vb1 idiom that has been adopted + * also by vb2. * @lock: pointer to a mutex that protects the vb2_queue struct. The * driver can set this to a mutex to let the v4l2 core serialize * the queuing ioctls. If the driver wants to handle locking @@ -467,6 +470,7 @@ struct vb2_queue { unsigned fileio_read_once:1; unsigned fileio_write_immediately:1; unsigned allow_zero_bytesused:1; + unsigned quirk_poll_must_check_waiting_for_buffers:1; struct mutex *lock; void *owner; |