From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
The generic vb2_request_validate helper function checks if
there are buffers in the request and if so, prepares (validates)
all objects in the request.
The generic vb2_request_queue helper function queues all buffer
objects in the validated request.
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
---
.../media/common/videobuf2/videobuf2-v4l2.c | 51 +++++++++++++++++++
include/media/videobuf2-v4l2.h | 4 ++
2 files changed, 55 insertions(+)
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 9c652afa62ab..364b1fea3826 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -1100,6 +1100,57 @@ void vb2_ops_wait_finish(struct vb2_queue *vq)
}
EXPORT_SYMBOL_GPL(vb2_ops_wait_finish);
+/*
+ * Note that this function is called during validation time and
+ * thus the req_queue_mutex is held to ensure no request objects
+ * can be added or deleted while validating. So there is no need
+ * to protect the objects list.
+ */
+int vb2_request_validate(struct media_request *req)
+{
+ struct media_request_object *obj;
+ int ret = 0;
+
+ if (!vb2_request_has_buffers(req))
+ return -ENOENT;
+
+ list_for_each_entry(obj, &req->objects, list) {
+ if (!obj->ops->prepare)
+ continue;
+
+ ret = obj->ops->prepare(obj);
+ if (ret)
+ break;
+ }
+
+ if (ret) {
+ list_for_each_entry_continue_reverse(obj, &req->objects, list)
+ if (obj->ops->unprepare)
+ obj->ops->unprepare(obj);
+ return ret;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(vb2_request_validate);
+
+void vb2_request_queue(struct media_request *req)
+{
+ struct media_request_object *obj, *obj_safe;
+
+ /*
+ * Queue all objects. Note that buffer objects are at the end of the
+ * objects list, after all other object types. Once buffer objects
+ * are queued, the driver might delete them immediately (if the driver
+ * processes the buffer at once), so we have to use
+ * list_for_each_entry_safe() to handle the case where the object we
+ * queue is deleted.
+ */
+ list_for_each_entry_safe(obj, obj_safe, &req->objects, list)
+ if (obj->ops->queue)
+ obj->ops->queue(obj);
+}
+EXPORT_SYMBOL_GPL(vb2_request_queue);
+
MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2");
MODULE_AUTHOR("Pawel Osciak <pawel@xxxxxxxxxx>, Marek Szyprowski");
MODULE_LICENSE("GPL");
diff --git a/include/media/videobuf2-v4l2.h b/include/media/videobuf2-v4l2.h
index 91a2b3e1a642..727855463838 100644
--- a/include/media/videobuf2-v4l2.h
+++ b/include/media/videobuf2-v4l2.h
@@ -303,4 +303,8 @@ void vb2_ops_wait_prepare(struct vb2_queue *vq);
*/
void vb2_ops_wait_finish(struct vb2_queue *vq);
+struct media_request;
+int vb2_request_validate(struct media_request *req);
+void vb2_request_queue(struct media_request *req);
+
#endif /* _MEDIA_VIDEOBUF2_V4L2_H */
--
2.18.0
