Serial MUX support

modulename: mux.ko

configname: CONFIG_SERIAL_MUX

Linux Kernel Configuration
└─>Device Drivers
└─>Character devices
└─>Serial drivers
└─>Serial MUX support
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Saying Y here will enable the hardware MUX serial driver for
the Nova, K class systems and D class with a 'remote control card'.
The hardware MUX is not 8250/16550 compatible therefore the
/dev/ttyB0 device is shared between the Serial MUX and the PDC
software console. The following steps need to be completed to use
the Serial MUX:

1. create the device entry (mknod /dev/ttyB0 c 11 0)
2. Edit the /etc/inittab to start a getty listening on /dev/ttyB0
3. Add device ttyB0 to /etc/securetty (if you want to log on as
root on this console.)
4. Change the kernel command console parameter to: console=ttyB0

source code:

depends
CONFIG_GSC
CONFIG_HAS_IOMEM
CONFIG_TTY

is selected by
CONFIG_SERIAL_MUX_CONSOLE