Sierra Wireless HSDPA WWAN

North American ThinkPads have the Sierra Wireless MC8765 card. European ThinkPads have the Sierra Wireless MC8755 card.

The only difference between the two is the frequency at which they support WCDMA. The MC8765 supports WCDMA800 and WCDMA1900, while the MC8755 supports only WCDMA2100.

Both models support GPRS and EDGE at 850, 900, 1800, and 1900MHz.

Both models are category 11/12 UMTS devices, meaning they support up to 1.8Mbps downstream using QPSK modulation. They do not support 16QAM modulation.

According to the T61 hardware maintenance manual, the T61 uses the MC8775, which is quad band EDGE (850/900/1800/1900) and tri band HSDPA (850/1900/2100).

Sierra Wireless MC8765 1199:6805 support

The model 2613-ETU T60p (and possibly others) has one of these cards which the linux sierra device driver does not automatically recognize (as of kernel 2.6.24.4, at least). While it's the same device in every other respect the PCI id isn't standard, presumably because IBM/Lenovo use their own PCI ids to restrict the use of arbitrary 3rd party cards. Using the 2.6.23+ hotplug infrastructure, we can cause the driver to claim it anyway and register serial devices in /dev for it.

To do this using the udev subsystem, edit or create the file /etc/udev/rules.d/98-local.rules file and add:

######
## Sierra Wireless MC8765 1199:6805 support
##
## My model 2613-ETU T60p contains a WAN device which the linux sierra
## device driver does not automatically recognize.  Using the 2.6.23+
## hotplug infrastructure, we can cause the driver to claim it.
##
## The 3-port interface works with this device, but there's not much point
## in registering the 2nd and 3rd since they are used for control purposes
## that we don't currently use under linux.
######

#SUBSYSTEM=="drivers", \
#	ACTION=="add", \
#	ENV{DEVPATH}=="/bus/usb-serial/drivers/sierra3", \
#	RUN+="/bin/sh -c 'echo 1199 6805  > /sys/bus/usb-serial/drivers/sierra3/new_id'"

SUBSYSTEM=="drivers", \
	ACTION=="add", \
	ENV{DEVPATH}=="/bus/usb-serial/drivers/sierra1", \
	RUN+="/bin/sh -c 'echo 1199 6805  > /sys/bus/usb-serial/drivers/sierra1/new_id'"

# TODO: fix this:
# This isn't quite right for sierra3, since it will always symlink
# wan_modem to the last created device; in the 3-port case that's not the
# device we actually want to refer to for modem interaction (we want the
# first device).  We could limit this using ENV{PHYSDEVDRIVER}="sierra1",
# but udev warns that this is deprecated and will be removed from a future
# kernel.
KERNEL=="ttyUSB*", \
	SYSFS{manufacturer}=="Sierra Wireless*", \
	SYMLINK+="wan_modem", \
	GROUP="uucp", \
	MODE="0666"

Sierra Wireless MC8775 1199:6813 Support

Some T61 units include the MC8775 model instead:

Bus 006 Device 002: ID 1199:6813 Sierra Wireless, Inc. 

This seems to work similarly (claimed by usbserial/sierra), but so far, I haven't been able to get it working as it appears to be locked.

Unlocking the modem

A locked modem will respond as follows:

AT+CPIN?
+CPIN: PH-NET PIN
OK

IBM support (first try) has told me that they cannot give me an unlock code. This forum thread claims that third-party unlocking software works: http://forums.lenovo.com/lnv/board/message?board.id=T_Series_Thinkpads&message.id=1523

Mdz 14:19, 6 August 2008 (CEST)