modules in 2.6.xx

[Renato Serodio <renato.serodio@gmail.com>]

I'm fighting to get Irda working on my machine, and I came to a point
where I would really like to understand so files in /etc . I searched
around in the web, looked at the kernel docs, but nothing really
enlightning came up. So here's my question:

In a 2.6 series, kernel (for the curious, 2.6.16.18), where is module
loading controlled? The following files are in my /etc:

modprobe.d/
       aliases
       alsa-base
       alsa-base-blacklist
       arch/
       arch-aliases -> arch/i386
       blacklist
       display_class
       irda-utils
       linux-sound-base_noOSS ->
/lib/linux-sound-base/noOSS.modprobe.conf
       pnp-hotplug

modules
modules.conf
modules.conf.old
modutils/
      0keep
      aliases
      alsa-base-blacklist
      arch
      linux-sound-base_noOSS ->
/lib/linux-sound-base/noOSS.modprobe.conf
      actions
      alsa-base
      apm
      irda-utils
      paths

Now, I recall that in the 2.4 series I had to edit some file (I fail to
recall which) to have sound and network modules loaded at boot. After
2.6 came along, the debian way to create kernels appears to have made
this unnecessary, and I have never messed with this files again.

Now, to get irda working, it so happens I have to load the smsc-ircc2
module, plus do some configuration inside files such as
/etc/modprobe.conf, /etc/sysconfig/irda and /etc/modules.conf.
Well, only the last file actually exists in my system.

I wonder if someone could provide me with some pointers to understand
module loading in the 2.6 kernels, where to RTFM, or anything else that
comes to your mind.

Cheers,

Renato