Hi,
Sorry for the late reply to this comment.

On Sat, 30 Apr 2011 11:17:53
+0100, Alan Cox [off-list ref] wrote :

quoted

--- a/drivers/tty/serial/8250.c
+++ b/drivers/tty/serial/8250.c

@@ -109,6 +109,13 @@ static unsigned int skip_txen_test; /* force

skip of txen test at init time */
 #define CONFIG_HUB6 1

 #include <asm/serial.h>
+
+/* TS-5500 related stuff */
+#ifdef CONFIG_SERIAL_8250_TS5500_485_TIMER
+#define TS5500_TIMER2_SPEED_ADDR        0x42
+#define TS5500_485_SERIAL_PORT                0x02
+#endif
+
 /*
  * SERIAL_PORT_DFNS tells us about built-in ports that have no
  * standard enumeration mechanism.   Platforms that can find all

@@ -437,6 +444,25 @@ static void au_serial_out(struct uart_port *p,

int offset, int value)
         __raw_writel(value, p->membase + offset);
 }

+#ifdef CONFIG_SERIAL_8250_TS5500_485_TIMER
+void serial8250_ts5500_set_termios(struct uart_port *port,
+                                   struct ktermios *new,
+                                   struct ktermios *old)
+{
+        u16 speed;
+
+        if (new->c_ospeed >= 9600 && port->line ==
TS5500_485_SERIAL_PORT) {
+                speed = ((115200 * 2) / new->c_ospeed);
+
+                /* This should be written by low byte followed by
high byte */
+                spin_lock_irq(&port->lock);
+                outb((speed & 0x0F), TS5500_TIMER2_SPEED_ADDR);
+                outb((speed >> 8), TS5500_TIMER2_SPEED_ADDR);
+                spin_unlock_irq(&port->lock);
+        }
+}
+#endif

Please don't put board specific magic in this file, we are desperately
trying to get rid of it.

quoted

+
 static unsigned int tsi_serial_in(struct uart_port *p, int offset)
 {
         unsigned int tmp;

@@ -2464,6 +2490,10 @@ serial8250_do_set_termios(struct uart_port

*port, struct ktermios *termios,
         /* Don't rewrite B0 */
         if (tty_termios_baud_rate(termios))
                 tty_termios_encode_baud_rate(termios, baud, baud);
+
+#ifdef CONFIG_SERIAL_8250_TS5500_485_TIMER
+        serial8250_ts5500_set_termios(port, termios, old);
+#endif
 }
 EXPORT_SYMBOL(serial8250_do_set_termios);

Provide your own set_termios method and then call into this one (which
is why it is exported)

I don't really understand how to do this. I've written my own
ts5500_serial8250_set_termios() function, which first makes a call to
serial8250_do_set_termios(), but I don't know how to make the platform
uses this one now. I've seen the plat_serial8250_port structure which
has a set_termios field, but I didn't find an example of usage of this
structure with this field. Maybe that's not the good way to "hook" the
serial8250_do_set_termios() function.
Could you please explain how to do this?

Regards,
Vivien.