+ * @refcount: reference count
+ * @done: IO completion struct
+ * @dev_id: unique device ID
+ * @device_alloc_chan_resources: allocate resources and return the
+ * number of allocated descriptors
+ * @device_free_chan_resources: release DMA channel's resources
+ * @device_memcpy_buf_to_buf: memcpy buf pointer to buf pointer
+ * @device_memcpy_buf_to_pg: memcpy buf pointer to struct page
+ * @device_memcpy_pg_to_pg: memcpy struct page/offset to struct page/offset
+ * @device_memcpy_complete: poll the status of an IOAT DMA transaction
+ * @device_memcpy_issue_pending: push appended descriptors to hardware