* to the userspace.
*/
req->count = allocated_buffers;
+ q->waiting_for_buffers = !V4L2_TYPE_IS_OUTPUT(q->type);
return 0;
}
memset(q->plane_sizes, 0, sizeof(q->plane_sizes));
memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx));
q->memory = create->memory;
+ q->waiting_for_buffers = !V4L2_TYPE_IS_OUTPUT(q->type);
}
num_buffers = min(create->count, VIDEO_MAX_FRAME - q->num_buffers);
* dequeued in dqbuf.
*/
list_add_tail(&vb->queued_entry, &q->queued_list);
+ q->waiting_for_buffers = false;
vb->state = VB2_BUF_STATE_QUEUED;
/*
* and videobuf, effectively returning control over them to userspace.
*/
__vb2_queue_cancel(q);
+ q->waiting_for_buffers = !V4L2_TYPE_IS_OUTPUT(q->type);
dprintk(3, "Streamoff successful\n");
return 0;
}
/*
- * There is nothing to wait for if no buffers have already been queued.
+ * There is nothing to wait for if the queue isn't streaming.
*/
- if (list_empty(&q->queued_list))
+ if (!vb2_is_streaming(q))
+ return res | POLLERR;
+ /*
+ * 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)
return res | POLLERR;
if (list_empty(&q->done_list))
* @retry_start_streaming: start_streaming() was called, but there were not enough
* buffers queued. If set, then retry calling start_streaming when
* queuing a new buffer.
+ * @waiting_for_buffers: used in poll() to check if vb2 is still waiting for
+ * buffers. Only set for capture queues if qbuf has not yet been
+ * called since poll() needs to return POLLERR in that situation.
* @fileio: file io emulator internal data, used only if emulator is active
*/
struct vb2_queue {
unsigned int streaming:1;
unsigned int retry_start_streaming:1;
+ unsigned int waiting_for_buffers:1;
struct vb2_fileio_data *fileio;
};