USB_BDRING_LEN_RX
emptybds = USB_BDRING_LEN_RX - ucoffs + swoffs;
ep->has_data = USB_BDRING_LEN_RX - emptybds;
(USB_BDRING_LEN_RX + 1);
bdring_len = USB_BDRING_LEN_RX;
bdring_len = USB_BDRING_LEN_RX;
bdring_len = USB_BDRING_LEN_RX;