Subject: Rename Sibyte duart devices?

From: Ralf Baechle <[email-masked]>
Date: Mon, 3 Dec 2007 13:08:18 +0000

Devices created by udev have been named duart? instead of the common
ttyS?.  This is a nuisance because it requires changes to all sorts of
config files such as /etc/inittab, /etc/securetty etc. to work.  I
suggest to kill the problem by the root by something like the below
patch.  Comments?

  Ralf

Signed-off-by: Ralf Baechle <[email-masked]>

 drivers/serial/sb1250-duart.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/serial/sb1250-duart.c b/drivers/serial/sb1250-duart.c
index 2d6c08b..0defbd6 100644
--- a/drivers/serial/sb1250-duart.c
+++ b/drivers/serial/sb1250-duart.c
@@ -897,7 +897,7 @@ static int __init sbd_console_setup(struct console *co, char *options)
 
 static struct uart_driver sbd_reg;
 static struct console sbd_console = {
-	.name	= "duart",
+	.name	= "ttyS",
 	.write	= sbd_console_write,
 	.device	= uart_console_device,
 	.setup	= sbd_console_setup,
@@ -925,7 +925,7 @@ console_initcall(sbd_serial_console_init);
 static struct uart_driver sbd_reg = {
 	.owner		= THIS_MODULE,
 	.driver_name	= "serial",
-	.dev_name	= "duart",
+	.dev_name	= "ttyS",
 	.major		= TTY_MAJOR,
 	.minor		= SB1250_DUART_MINOR_BASE,
 	.nr		= DUART_MAX_CHIP * DUART_MAX_SIDE,

---

From: Thiemo Seufer <[email-masked]>
Date: Mon, 3 Dec 2007 14:14:26 +0000

> suggest to kill the problem by the root by something like the below

Debian uses such a patch since forever to avoid all the trouble.

Thiemo

---

From: "Maciej W. Rozycki" <[email-masked]>
Date: Mon, 3 Dec 2007 14:30:47 +0000 (GMT)

> suggest to kill the problem by the root by something like the below

 Well, there is no problem with naming your device nodes in the filesystem
however you like and the only place that only cares is the "console="
command line option.  I think the root is ttyS devices should really be
only used for 8250-based devices and if you plug a standard PC serial
option card into one of the PCI slots, then all the hell will break loose.
I might be wrong though and the issue I am referring to may have gone now.

 [Sent twice to reach linux-serial.]

  Maciej

---

From: "Kaz Kylheku" <[email-masked]>
Date: Mon, 3 Dec 2007 13:41:09 -0800

Ralf Baechle wrote:
> config files such as /etc/inittab, /etc/securetty etc. to work.

I can see this kind of a change being somewhat sneaky; some Linux users
on SiByte systems have already worked around for the duart naming not by
patching the kernel but by modifying their text configurations to use
the duart naming. After they figure out why, after upgrading to a new
kernel, their system doesn't work any more, they will still have the
problem that the newer and older kernel require different text
configuration in the file system with respect to the tty devices. It's
nice to be able to pull out an older kernel and boot with it, without
having to remember a list of things to tweak.

To be forward and backward compatible, the kernel should perhaps offer
the device under both aliases: /etc/TTYSx and /etc/duartx.

Kaz "Kompatibility Kurmudgeon" Kylheku