}
EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers);
+/**
+ * __vb2_dqbuf() - bring back the buffer to the DEQUEUED state
+ */
+static void __vb2_dqbuf(struct vb2_buffer *vb)
+{
+ struct vb2_queue *q = vb->vb2_queue;
+ unsigned int i;
+
+ /* nothing to do if the buffer is already dequeued */
+ if (vb->state == VB2_BUF_STATE_DEQUEUED)
+ return;
+
+ vb->state = VB2_BUF_STATE_DEQUEUED;
+
+ /* unmap DMABUF buffer
+ * TODO: this unpins the buffer(dma_buf_unmap_attachment()).. but
+ * really we want to do this just after DMA, not when the
+ * buffer is dequeued..
+ */
+ if (q->memory == V4L2_MEMORY_DMABUF) {
+ for (i = 0; i < vb->num_planes; ++i) {
+ if (!vb->planes[i].dbuf_mapped)
+ continue;
+ call_memop(q, unmap_dmabuf, vb->planes[i].mem_priv);
+ vb->planes[i].dbuf_mapped = 0;
+ }
+ }
+}
+
/**
* vb2_dqbuf() - Dequeue a buffer to the userspace
* @q: videobuf2 queue
return ret;
}
- /* TODO: this unpins the buffer(dma_buf_unmap_attachment()).. but
- * really we want to do this just after DMA, not when the
- * buffer is dequeued..
- */
- if (q->memory == V4L2_MEMORY_DMABUF) {
- unsigned int i;
-
- for (i = 0; i < vb->num_planes; ++i) {
- call_memop(q, unmap_dmabuf, vb->planes[i].mem_priv);
- vb->planes[i].dbuf_mapped = 0;
- }
- }
-
switch (vb->state) {
case VB2_BUF_STATE_DONE:
dprintk(3, "dqbuf: Returning done buffer\n");
__fill_v4l2_buffer(vb, b);
/* Remove from videobuf queue */
list_del(&vb->queued_entry);
+ /* go back to dequeued state */
+ __vb2_dqbuf(vb);
dprintk(1, "dqbuf of buffer %d, with state %d\n",
vb->v4l2_buf.index, vb->state);
- vb->state = VB2_BUF_STATE_DEQUEUED;
return 0;
}
EXPORT_SYMBOL_GPL(vb2_dqbuf);
* Reinitialize all buffers for next use.
*/
for (i = 0; i < q->num_buffers; ++i)
- q->bufs[i]->state = VB2_BUF_STATE_DEQUEUED;
+ __vb2_dqbuf(q->bufs[i]);
}
/**
}
EXPORT_SYMBOL_GPL(vb2_streamoff);
+/**
+ * vb2_expbuf() - Export a buffer as a file descriptor
+ * @q: videobuf2 queue
+ * @eb: export buffer structure passed from userspace to vidioc_expbuf
+ * handler in driver
+ *
+ * The return values from this function are intended to be directly returned
+ * from vidioc_expbuf handler in driver.
+ */
+int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb)
+{
+ struct vb2_buffer *vb = NULL;
+ struct vb2_plane *vb_plane;
+ int ret;
+ struct dma_buf *dbuf;
+
+ if (q->memory != V4L2_MEMORY_MMAP) {
+ dprintk(1, "Queue is not currently set up for mmap\n");
+ return -EINVAL;
+ }
+
+ if (!q->mem_ops->get_dmabuf) {
+ dprintk(1, "Queue does not support DMA buffer exporting\n");
+ return -EINVAL;
+ }
+
+ if (eb->flags & ~O_CLOEXEC) {
+ dprintk(1, "Queue does support only O_CLOEXEC flag\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Find the plane corresponding to the offset passed by userspace.
+ */
+ if (eb->type != q->type) {
+ dprintk(1, "invalid type %u\n", eb->type);
+ return -EINVAL;
+ }
+ if (eb->index >= q->num_buffers) {
+ dprintk(1, "invalid buffer %u\n", eb->index);
+ return -EINVAL;
+ }
+ vb = q->bufs[eb->index];
+ if (eb->plane >= vb->num_planes) {
+ dprintk(1, "invalid plane %u\n", eb->plane);
+ return -EINVAL;
+ }
+ vb_plane = &vb->planes[eb->plane];
+
+ dbuf = call_memop(q, get_dmabuf, vb_plane->mem_priv);
+ if (IS_ERR_OR_NULL(dbuf)) {
+ dprintk(1, "Failed to export buffer %d, plane %d\n",
+ eb->index, eb->plane);
+ return -EINVAL;
+ }
+
+ ret = dma_buf_fd(dbuf, eb->flags);
+ if (ret < 0) {
+ dprintk(3, "buffer %d, plane %d failed to export (%d)\n",
+ eb->index, eb->plane, ret);
+ dma_buf_put(dbuf);
+ return ret;
+ }
+
+ dprintk(3, "buffer %d, plane %d exported as %d descriptor\n",
+ eb->index, eb->plane, ret);
+ eb->fd = ret;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(vb2_expbuf);
+
/**
* __find_plane_by_offset() - find plane associated with the given offset off
*/