Agere Systems L56xM+S (Mars-2)

Chipset data:

Agere Systems formerly Lucent Technologies, datasheet
PCI bus controllerless (HCF) modem
Linux support
Agere/Lucent has not released an official Linux driver for the Mars-2 chipsets.
However, they do supply proprietary code in kit form to the volunteer developers.

Volunteer "Linmodem" project: LTModem Drivers for Linux
  L56DM+S = DSP1646 + CSP1034AH (MQFP) [+ optional CSP1027] (Desktop)
  L56LM+S = DSP1646 + CSP1034AH (TQFP) [+ optional CSP1027] (Laptop)

  1027      Audio Codec              48-pin TQFP
  1034AH    Line Codec               44-pin MQFP or 48-pin TQFP
  1646      Mars-2 DSP               100-pin TQFP
MFQP=Metric Quad Plat Package
TFQP=Thin Quad Flat Package
DSP1646 package HV90P-T package V90P T-RECV package DSP1646 package 1034AH-J 1034C-J
Typical application
Modem with L56DM+S chipset
Rob Clark