[ltp] T21 /dev/ttyS0

[Rob Mayoff]

+---------- On Sep 16, Manolis Stamatogiannakis said:
> Hi, I have installed gentoo linux on a TP T21.
> There is no /dev/ttyS0 though. I am using devfs.
> How do I create the serial port device? Did anybody
> gave similar problems with linux on his TP?
>
> The serial driver is bult in the kernel (gentoo-2.4.19-r9).
> Here is the part of the dmesg output:

If the serial ports aren't enabled at boot time, then devfs won't have
the device nodes for the serial ports. In my experience, devfs will
NOT create the device nodes later if you enable the serial ports after
boot (using tpctl or setpnp), when the serial driver is built in to the
kernel.

If you absolutely need the serial ports without rebooting, and you're in
this situation, then you can create the device nodes somewhere else, for
example as /tmp/ttyS0 and /tmp/ttyS1.  The major number is 4 and the
minor numbers are 64 (for ttyS0) and 65 (for ttyS1).

I rebuilt my kernel with the serial driver as a module. This way, if the
serial ports are disabled when I boot, I can enable them with tpctl or
setpnp and then load the module. When the serial driver module loads, it
creates the devfs device nodes if the serial ports are enabled.