[vox-tech] how *not* to load the serial module at boot time?

[Matt Holland]

Hey all,

Does anyone out there know how RedHat (7.3, if it matters) decides when 
(and if) to load the serial port driver, and if so, how to stop it from 
loading?  I ask because I've just started playing with lirc (Linux 
Infrared Remote Control -- very nifty) with my newly-built home-brew 
serial IR receiver, but the lirc_serial driver can't grab the port if 
the serial driver has already been loaded.  I compiled the serial driver 
as a module when I built my kernel, but I still get:

Serial driver version 5.05c (2001-07-08) with MANY_PORTS MULTIPORT 
SHARE_IRQ SER
IAL_PCI ISAPNP enabled
ttyS00 at 0x03f8 (irq = 4) is a 16550A
ttyS01 at 0x02f8 (irq = 3) is a 16550A
...
lirc_serial: port 03f8 already in use, proceeding anyway
lirc_serial: compile the serial port driver as module and
lirc_serial: make sure this module is loaded first
lirc_serial: auto-detected active low receiver

in my dmesg output.  The problem is that the serial driver is getting 
loaded before anything listed in /etc/modules.conf.  Nothing works until 
I do:

# setserial /dev/ttyS0 uart none
# rmmod lirc_serial
# insmod lirc_serial

It's possible that I had to restart lircd after that... I don't remember 
for certain whether I did or not.  In any case, it seems clear that I 
could just put those commands (followed by the daemon restart, if 
necessary) at the end of rc.local, and learn to ignore the error 
messages during boot (after all, I have no problem ignoring X when it 
complains about missing fonts ;).  However, it seems like just stopping 
the serial module from loading in the first place would be the more 
elegant solution.

For those eager Debian users out there... the lirc documentation 
mentioned modifying /etc/serial.conf on Debian... no such file in a 
RedHat installation.  Also, I grep'ed the init scripts for 'serial' and 
didn't find anything enlightening.

Incidentally, for those of you who don't always sit *at* your computer 
when listening to mp3's, watching DVD's, whatever, I highly recommend 
looking into lirc (www.lirc.org).  I'm a firm believer that a little 
soldering now and then is good for the soul :)  I can't say enough about 
the coolness of this project!

Thanks,
Matt