sc16is7xxi2c_read_register_direct
error = sc16is7xxi2c_read_register_direct(isc->sc_tag, isc->sc_addr,
error = sc16is7xxi2c_read_register_direct(isc->sc_tag, isc->sc_addr,
error = sc16is7xxi2c_read_register_direct(tag, addr, reg, 0, buf, 1);