if (flow == 'r')
termios.c_cflag |= CRTSCTS;
+ /*
+ * some uarts on other side don't support no flow control.
+ * So we set * DTR in host uart to make them happy
+ */
+ port->mctrl |= TIOCM_DTR;
+
port->ops->set_termios(port, &termios, NULL);
co->cflag = termios.c_cflag;