send_port_cmd
return send_port_cmd(port->port, feature, on, NULL, 0);
status = send_port_cmd(port, UMPC_OPEN_PORT, open_settings, NULL, 0);
status = send_port_cmd(port, UMPC_START_PORT, 0, NULL, 0);
send_port_cmd(port, UMPC_CLOSE_PORT, 0, NULL, 0);
status = send_port_cmd(edge_port->port, UMPC_SET_CONFIG, 0, config,
return send_port_cmd(port, UMPC_PURGE_PORT, mask, NULL, 0);