usbd_intr_transfer
err = usbd_intr_transfer(sc->sc_wr_xfer, sc->sc_wr_pipe,
err = usbd_intr_transfer(xfer, sce->pipeh, 0,
err = usbd_intr_transfer(sc->sc_oxfer, sc->sc_opipe, 0,
err = usbd_intr_transfer(sc->sc_oxfer, sc->sc_opipe, 0,
usbd_status usbd_intr_transfer(struct usbd_xfer *, struct usbd_pipe *,