Sprint U300 3G/4G Modem

I just got a Sprint U300 3G/4G modem through work and of course had to test under Ubuntu Karmic.

So let's see what we got

-=[petter@miniscule /home/petter]=- lsusb
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 005: ID 16d8:6002 CMOTECH Co., Ltd. 
Bus 001 Device 003: ID 0409:005a NEC Corp. HighSpeed Hub
Bus 001 Device 002: ID 13d3:5071 IMC Networks 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 002: ID 0b05:b700 ASUSTek Computer, Inc. Broadcom Bluetooth 2.1
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
-=[petter@miniscule /home/petter]=- 

So there it is:

Bus 001 Device 005: ID 16d8:6002 CMOTECH Co., Ltd. 

So, let's turn this into a servial device

sudo modprobe usbserial vendor=0x16d8 product=0x6002

Looking at the dmesg output also shows us that we now have some new devices

[15020.190930] USB Serial support registered for generic
[15020.190986] usbserial_generic 1-5.1:1.0: generic converter detected
[15020.191123] usb 1-5.1: generic converter now attached to ttyUSB0
[15020.191141] usbserial_generic 1-5.1:1.1: generic converter detected
[15020.191235] usb 1-5.1: generic converter now attached to ttyUSB1
[15020.191251] usbserial_generic 1-5.1:1.2: generic converter detected
[15020.191345] usb 1-5.1: generic converter now attached to ttyUSB2
[15020.191375] usbcore: registered new interface driver usbserial_generic
[15020.191380] usbserial: USB Serial Driver core

Let's create an udev rule for this so we don't have to run this command manually every time we attach the modem.
Create a new file, /etc/udev/rules.d/50-u300modem.rules (you can of course name any way you like).

ACTION!="add", GOTO="3G_End"

SUBSYSTEMS=="usb", ATTRS{idProduct}=="6002", ATTRS{idVendor}=="16d8", RUN+="/sbin/modprobe usbserial vendor=0x16d8 product=0x6002"
LABEL="3G_End"

Restart udev

sudo restart udev
udev start/running, process 2955

That should be all that there is, your modem should now show up under the Network Manager applet. Select your country and provider and enjoy.