Research mpt

The system contains a tool called mpt which allows to route some of the MSM modem traffic to the microUSB connection and such enables a passthru mode where the host PC could use the modem directly. That way the modem can be configured with some special software from Quallcom.

root@castle:/var/home/root# mpt
Usage:
To enable passthru: mpt [port_spec]
To disable passthru: mpt disable (or mpt x)

[port_spec]
dun (or '0')       : DUN (port0) only
diag (or 'd')      : Diag port only
dun,diag (or '0d') : DUN (port0) and Diag port
diag,gps           : Diag port and GPS port
userial            : Serial passthru with USB cable
serial             : Serial passthru with Serial cable

It shows up like this on my linux box:

[16675.933683] usb 2-4.4: new full speed USB device using ohci_hcd and address 10
[16676.032663] usb 2-4.4: not running at top speed; connect to a high speed hub
[16676.048665] usb 2-4.4: New USB device found, idVendor=0830, idProduct=8003
[16676.048675] usb 2-4.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[16676.048682] usb 2-4.4: Product: Pre
[16676.048686] usb 2-4.4: Manufacturer: Palm Inc.
[16676.048876] usb 2-4.4: configuration #1 chosen from 1 choice

When loading usbserial with the USB IDs we get two serial devices when using dun mode:

root@castle:/var/home/root# mpt dun
** Message: serviceResponse Handling: 2, {"returnValue":true}
Pass-through enabled for DUN

usbserial_generic 1-1:1.0: generic converter detected
usb 1-1: generic converter now attached to ttyUSB0
usbserial_generic 1-1:1.1: generic converter detected
usb 1-1: generic converter now attached to ttyUSB1

You can find diagnostic mode serial drivers at https://sites.google.com/site/dogber1/blog/passthru-drivers.zip and http://www.herrie.org/passthru-driverstp4g.zip

If your device gets stuck in diag mode, use #*USBPASS# to turn it off. You may need a code to do this, which you can get from http://www.herrie.org/tpkeygen.html