Hi, We have problem with automatic flow control (i.e. auto RTS/CTS handshaking) in our uart driver (men_z135_uart.c). It's probably less a technical but a problem with me understanding the API. I active the hardware auto flow control feature on the CRTSCTS flag in my uart_ops->set_termios() function. But then the RTS flag is set on every call of the uart_ops->set_mctrl() function, this seems to confuse the hardware. Is there a way to tell the tty layer that flow control is handled solely by hardware? I.e. is there a way of telling serial core to leave out the calls to uart_set_mctrl()/uart_clear_mctrl() in uart_throttle()/uart_unthrottle(), or is setting UPF_FLOW_HARD and then implementing a dummy port->ops->{un}throttle() the correct way? Are there any drivers that use a hardware's automatic flow control feature I can use as an example? A fast grep on AFE reveals some spots, but I can't really find a difference to my implementation. Thanks in advance, Johannes -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html