cp2112iic_send_req
err = cp2112iic_send_req(sc, &req, msgs[i].len + 5);
err = cp2112iic_send_req(sc, &req, sizeof(req));
err = cp2112iic_send_req(sc, &req, msgs[i].len + 3);
err = cp2112iic_send_req(sc, req_data, req_len);