ModemManager: new 'wavecom' gsm plugin for Sierra Wireless Airlink FXT modems

[Aleksander Morgado <aleksander lanedo com>]

Hi all,


Finished implementing the basic ModemManager support for the Sierra
Wireless Airlink Fastrack Xtend GSM/UMTS modems [1]. The plugin was
developed using a Fastrack Xtend FXT009 (GPRS/EDGE) modem, but
implemented to support also 3G-based models (although completely
untested that part). There is a CDMA modem model as well, but don't
think this plugin could handle it without more modifications.


This development is ready for review in the 'plugin-wavecom' branch in
the following Gitorious repository [2]:
   git://gitorious.org/lanedo/modemmanager.git


The changes w.r.t to the generic GSM plugin are:

  a) AT+CPIN? replies are not ended with OK. A custom regex match was
added to support CPIN? replies without OK.

  b) Disabled default power-up comand, AT+CFUN=1. This command does a
full software reset in the device, including the USB stack, so the
connection is closed. No additional command seems to be needed, as the
modem wakes up by default in CFUN=1 (full functionality) mode. Anyway,
an additional check was added during initialization so that this mode is
ensured.

  c) Enabled RTS/CTS instead of XOFF/XON flow control.

  d) Implemented get_access_technology() using AT+WGPRS=9,2 to query
network capabilities

  e) Ensure the modem uses the highest possible mobile class. These
modems can be configured to use different mobile classes. For each kind
of modem, the best mobile class is the highest one available, in the
following order:
     - Class A  (3G only mode)
     - Class B  (PS or CS, GPRS/EDGE or GSM)
     - Class CG (PS only, GPRS/EDGE)
     - Class CC (CS only, GSM)

  f) Implemented set_allowed_mode() and get_allowed_mode(), for both 2G
and 3G based modems (using AT+WWSM command in the 3G case).

  g) Implemented set_band() and get_band() for 2G modems (with AT+WMBS)
and 3G modems (with AT+WUBS).


[1]
http://www.sierrawireless.com/productsandservices/AirLink/Programmable_Modems/Fastrack%20Series.aspx
[2] https://gitorious.org/lanedo/modemmanager


Cheers,

-- 
Aleksander