Rather than that ...
Can you get one of the drivers from xusa
http://www.usa-x.org/forum/modules.php?name=Downloads
(Unfortunately they are kernel version specific e.g. the kernel
with RH 7.1). Also, I'm not sure they actually work :(
(actually, it wouldn't take much to emulate the driver)
Then use strace.
strace doesn't help much with ioctls, so to improve the information
add/replace with the contents of
http://members.optushome.com.au/jhonan/dst/dst-strace-ioctl.tar.gz
to the source of strace.
With strace, only bother with open,close and ioctl. Also be sure
to follow forks.
In any case, I reckon what you'll see is
1. the DST-CI coming back from the driver.
2. a big fat 0x14 / 0x15 ioctl which is some sort of read / write
to the CI module. That will be the beast!
Simple to say, tedious to do.
Waaaay ahead of you there.. The driver they provide does not work with
my card, it fails the tuner ioctl.. I'm now looking to get RH 7.1 which
is what they compiled it up with, but with the serious bandwidth
cap/cost up here it's not worth me downloading it so I'm looking for a
copy on disk somwehere.