Linux on iLamp - modem sound iMac G4 Flat Panel 15 -- a Report

[Chris Hafey]

Linux on iLamp - modem sound iMac G4 Flat Panel 15 -- a Report

Finally got Marc Boucher's hcfusbmodem program working, which
brought the iLamp internal modem on-line (it's a Conexant HCF
Cadmus2 56K Faxmodem USB).  I'm composing this in a shell account
at an ISP 30 miles from here ..  the modem *really* works.
Under Linux.

This is an important matter; I had to boot Mac OS X to use the
modem previously.  No more!

quality:

ppp0      Link encap:Point-to-Point Protocol  
          inet addr:***.***.78.55  P-t-P:***.***.78.1  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1524  Metric:1
          RX packets:49377 errors:0 dropped:0 overruns:0 frame:0
          TX packets:51506 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:4711869 (4.4 MiB)  TX bytes:3286503 (3.1 MiB)

(just light interactive work; no d/l). (seems excellent to me).

Reference Linux distrib. for my iLamp report is Debian 3.0;
I am corresponding with a YDL 2.3 user who reports similar
results to mine, in most regards.

Kernel report (after a modprobe):

Manufacturer: HCF USB V.90 Data/Fax Modem
Product: Apple internal modem
SerialNumber: ********
usb.c: usbhcf driver claimed interface ********
osusb.c: usbhcf is detected

(asterisk mine to obscure numbers)

That was a tough one; still not sure just what is going on, but
the modem works (as a modem, anyway).  Learned the name 'Conexant'
and the term 'HCF' from prowling around in Mac OS X -- saw something
in a Darwin log, also.  I didn't know for sure it was supposed to
work (at all) on the iLamp.  It does; just be sure to ATX3 if there
is no dialtone detect.  minicom, chat and ppp all work fine.


Concurrent sound was broken, though -- 2.4.20-ben1 has quite a
bit more in the dmasound subdirectory for the tas3001c.c  -- 
it's the Tumbler -- ended up removing the dmasound contents entirely
and replacing it with that from 2.4.19-4a.  Now I have both modem
and sound working at the same time (whereas the HCF USB modem driver
from http://www.mbsi.ca/cnxtlindrv wasn't functional under 2.4.19-4a
for reasons as-yet undetermined; which is what prompted me to go with
the branded benh kernel from linuxppc.org).  I realized the kernel
config wasn't fine-grained enough to configure 'dmasound' more
accurately, so I figured replacing the entire dmasound source with
one I already had working was a good idea -- it does work.  No idea
if that's sound (cough) engineering practice or not.

Also working: Mac-On-Linux ('startx -- -depth 24' helps) as well
as X11 (use the framebuffer) and a Kensington TurboBall (acts like
a three button mouse).  Console video comes up as 128x48 chars.
Ethernet worked fine first kernel build (or earlier from distrib.
kernels; can't recall now).

On my TODO list: find ways to 1. get X11/FBDev to behave when idle
(makes the LCD roll and flash badly -- I switch to console video every
time before walking away from the machine);  2. adjust backlight
intensity level control (work-around is to set it in Mac OS X and
be sure to login, open 'Macintosh HD' or do something else to 'lock'
the intensity change to nvram or where-ever it is stored; then it
will carry over to the Linux side); 3. sleep / APM related things
(energy savers) and hard-disk spindown.

I don't have a printer to test with.

Have read from the CDROM drive, and Mac-On-Linux appears to
consult it as well (haven't tested that).

Keymaps were problematic; I developed a work-around (ssh to the
machine and activate other keymaps, since ssh won't be affected
by the same problem -- it's running on another keyboard/display).
This problem may be a Debianism only.

It's not the kernel -- same source built two different ways needs
different keymaps.

Working (collecting) documentation and correspondence, but I know
I'll get side-tracked.  I wanted to say *something* publicly on
this, since iLamp remarks (save the 'magazine' talk which doesn't
help us here) are far and few between wrt Linux on the iLamp.

Hence this disorganized message.

Christopher W Hafey
Torrington CT USA