Re: [PATCH] serial/arc-uart: Add new driver

[Vineet Gupta <Vineet.Gupta1@synopsys.com>]

On Friday 28 September 2012 06:32 PM, Alan Cox wrote:

>> +static void
>> +arc_serial_set_termios(struct uart_port *port, struct ktermios
>> *termios,
>> +		       struct ktermios *old)
>> +{
>> +	struct arc_uart_port *uart = (struct arc_uart_port *)port;
>> +	unsigned int baud, uartl, uarth, hw_val;
>> +	unsigned long flags;
>> +
> Two things here. Firstly you want to write the actual baud back to the
> termios (tty_termios_encode_baud_rate) unless B0 is set.
>
> Secondly if you don't support hardware flow control, character size
> setting etc then you need to set those bits back so the caller knows.
> Two ways to do that. Either initialise the default termios for the tty
> type to the correct values and use tty_termios_copy_hw() or set them in
> the termios handler.

Just to give you an idea, is something on the lines of following OK for
both the above points above !

-       uart_update_timeout(port, termios->c_cflag, baud);
+       new->c_cflag &= ~(CMSPAR|CRTSCTS);  /* Don't care for
parity/flow ctrl */
+
+       if (old)
+               tty_termios_copy_hw(new, old);
+
+       /* Don't rewrite B0 */
+       if (tty_termios_baud_rate(new))
+               tty_termios_encode_baud_rate(new, baud, baud);
+
+       uart_update_timeout(port, new->c_cflag, baud);
 

Respun patch to follow shortly.

Thx,
Vineet