ALIX is a pretty standard x86 box and stock Debian runs perfectly -- no special port needed nor any binary drivers. Since quite a while there has been kernel support in mainline for the box's LEDs too, through the led subsystem. Everything works like a charm.
That being said, the box does not include WiFi, ADSL, GSM/GPS or anything like that. It just has miniPCI slots for people to buy their own cards. Some of them may require firmware, although there are certainly e.g. WiFi cards that don't.