TopInstalling lirc_serial without a new kernel

You can use the lirc_serial driver without building a new kernel, however, your keyboard will not be available until the machine has nearly finished booting. You would edit /etc/rc.local and add "setserial /dev/ttyS1 uart none" to release the serial port, then next add "modprobe lirc_serial" as the next line. The last few lines of /etc/rc.local should look something like this:

    cat /etc/security/msec/issue.net.$SECURE_LEVEL > /etc/issue.net
  elif [ -f /etc/security/msec/issue.net ]; then
    cat /etc/security/msec/issue.net > /etc/issue.net
  else
    rm -f /etc/issue.net
  fi
fi

touch /var/lock/subsys/local

# activate the WebPal IR keyboard stuff
setserial /dev/ttyS1 uart none
modprobe lirc_serial
modprobe uinput
/usr/sbin/lircd -d /dev/lirc0
/usr/sbin/lirc_keybd

Test the driver installation with "setserial /dev/ttyS1 uart none" and "modprobe lirc_serial", it should quietly run and a /dev/lirc0 should now appear in the /dev directory. If it does not, then check the /var/log/messages and file under /var/log/kernel to see what kind of error you had. Note that the lircd and lirc_keybd daemons are also being activated as well?

TopInstalling lirc_serial earlier in the boot process

Later, when stuff is tested and working, you will want to have the module loaded at boot time. Follow the procedure for this with your distro of linux. You will have to compile your own kernel and make the 8250 driver a loadable module. Otherwise, the serial port kernel module will grab all the serial ports and make it impossible for lirc_serial to get at the one we configured it for. The entry you want for this is under (make menuconfig) "Device Drivers | Character devices | Serial drivers" and change "8250/16550 and compatible serial support" to "M" (module). Save out the config and build your kernel as normal (make ; make modules_install ; make install).

Boot the machine, then run "uname -r" to verify that your new kernel is being used. Once you verify this, check to see that no serial ports yet exist (8250 module is not yet loaded) with "ls /dev/ttyS*", you should see nothing (no /dev/ttyS0, /dev/ttyS1, ...). If you see serial ports, check to see if the 8250 module was autoinstalled by the hardware detection logic while booting "lsmod 8250". If it is there, do a "rmmod 8250" and check to see there are no serial ports. If you still see serial ports, then you didn't compile the kernel correctly. :( Something broke.

Once you've verified the operation of the 8250 module, that it is not loading serial ports when you boot. You can add lirc_serial then 8250 to your /etc/modules files. On Mandrake10, I added two lines to /etc/modprobe.preload:

# /etc/modprobe.preload: kernel modules to load at boot time.
#
# This file should contain the names of kernel modules that are
# to be loaded at boot time, one per line. Comments begin with
# a `#', and everything on the line after them are ignored.
# this file is for module-init-tools (kernel 2.5 and above) ONLY
# for old kernel use /etc/modules

lirc_serial
8250
uinput

This will load the lirc_serial module fairly early in the system boot process. Please note, the uninput driver module needs to also be loaded. The kernel cannot sense that the lirc_keybd daemon will want this, so we will manually specify it to be loaded.

I suspect that you could also go as far as to modify the kernel sources to include the lirc_serial into your running kernel. The advantage would be that you could then have an initrd.img which could load the driver even earlier? That is more work than I need to do here, it is beyond the scope of what I wanted to accomplish, for now. ;)

TopCleanup the IVTV modules statements

You've probably already gotten MythTV running and checked out before you moved on to trying out this "keyboard idea of Tom's"? We need to change some of those PVR250 / PVR350 IVTV aliases and such in /etc/modules.conf file. We need to comment out the loading of the ivtv lirc driver, my modules.conf looks like this for a twin PVR250MCE setup:

alias char-major-81 videodev
alias char-major-81-0 ivtv
#alias char-major-61 lirc_device
options ivtv debug=1
options tuner type=2
options msp3400 once=1 simple=1
add below ivtv msp3400 saa7115 tuner
#add above ivtv lirc_dev lirc_i2c

If we don't do this, then things will get confusing, more likely you will end up with both a /dev/lirc0 and a /dev/lirc1 IR device. I don't think that there would be a conflict, but you would then need to decide which is which device that is actually lirc_serial appearing in the device directory. Better to comment out the ivtv stuff for now. You can always put it back later if you decide to, or you cannot get all this working. :-P