The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
kernel driver and a user level application. Together these components
support direct attachment to public switched telephone networks (PSTNs)
and support selected world wide countries.

This version of the ACP Modem driver supports the IBM Thinkpad 600E,
600, and 770 that include on board ACP modem hardware.

The modem also supports the standard communications port interface
(ttySx) and is compatible with the Hayes AT Command Set.

The user level application needed to use this driver can be found at
the IBM Linux Technology Center (LTC) web site:
<http://www.ibm.com/linux/ltc/>.

If you own one of the above IBM Thinkpads which has the Mwave chipset
in it, say Y.

To compile this driver as a module, choose M here: the
module will be called mwave.

source code:

drivers/char/mwave/