The Conexant PCI ADSL Modem is available from several locations at a low cost in New Zealand. World-Net sell it branded as an Access-Runner and it is also available from Dick Smith Electronics as product XH1137. This modem contains a Conexant Tigris chipset and is reasonably easy to get going it linux once you know what to do. The basic steps are below. This is probably going to be quite debian specific seeing as I only run debian.
The only quirk I have found with the modem so far is that the lights on the back do not go. So if your modem looks dead don't be fooled! Newer revisions of the card (such as those sold by Dick Smith) do not have status lights at all, so this quirk of the driver isn't much of a loss.
The authoritative reference for the kernel module that you need seems to be http://www.zweije.nl.eu.org/%7Evzweije/accessrunner/ the information below is a summary of this page and a refactoring of the previous information found on this wiki page.
|Kernel configuration section||Description||.config Define|
|Networking options||Asynchronous Transfer Mode (ATM)||CONFIG_ATM|
|Network device support||PPP (point-to-point protocol) support||CONFIG_PPP|
|Network device support||PPP over ATM||CONFIG_PPPOATM|
If you are using a 2.6 kernel you also need to ensure that CONFIG_REGPARM is disabled in your kernel. It is also suggested that you turn of SMP and PREEMPT.
|Kernel 2.4 and earlier||http://patrick.spacesurfer.com/adsl/driver-2.4-latest.tar.bz2|
The 2.6 drivers have been tested and found to work fine with 2.6.12 by MattBrown
NOTE: make install tries to install the init script into /etc/rc.d/init.d/ so you might need to edit the Makefile to point it to the correct location for your distribution (ie. for debian, etc.)
to update your module dependencies. Under 2.4.26 I get a few warnings about unresolved symbols which is slightly worrying, but everything seems to work ok.
NOTE: You can't just insmod / modprobe the driver, see the following section for how to get it to work.
Actually getting the driver to load successfully is another story altogether.
This information comes directly from /proc/net/atm/CnxAdsl:0
The modem driver is now up and running. However before you can actually get on the internet you will need to configure PPPoA.
Setting up PPPoA in Linux is documented on the following page LinuxPPPoA.