[patch 02/15] Fix tty speed handling on 8250

[Greg KH <gregkh@suse.de>]

[-- Attachment #1: fix-tty-speed-handling-on-8250.patch --]
[-- Type: text/plain, Size: 1189 bytes --]

2.6.25-stable review patch.  If anyone has any objections, please let us
know.

------------------
From: Alan Cox <alan@lxorguk.ukuu.org.uk>

commit e991a2bd4fa0b2f475b67dfe8f33e8ecbdcbb40b upstream.

We try and write the correct speed back but the serial midlayer already
mangles the speed on us and that means if we request B0 we report back B9600
when we should not.  For now we'll hack around this in the drivers and serial
code, pending a better long term solution.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/serial/8250.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -2174,7 +2174,9 @@ serial8250_set_termios(struct uart_port 
 	}
 	serial8250_set_mctrl(&up->port, up->port.mctrl);
 	spin_unlock_irqrestore(&up->port.lock, flags);
-	tty_termios_encode_baud_rate(termios, baud, baud);
+	/* Don't rewrite B0 */
+	if (tty_termios_baud_rate(termios))
+		tty_termios_encode_baud_rate(termios, baud, baud);
 }
 
 static void

--