Looking to add support for Huawei EC156 (HSIA) USB modem

[Mayuresh <mayuresh%acm.org@localhost>]

I am running NetBSD 6.0 i386.

Would like to use above mentioned modem on NetBSD.

dmesg shows only this much:
u3ginit0 at uhub5 port 2: Switching to 3G mode

tip ucom0 shows:
tip: /dev/ttyU0: Device not configured
tip: link down

Looked at /usr/src/sys/dev/usb. Doesn't look like above modem is readily
supported.

Is some code change required here to try and support this modem or is
there any other generic treatment for USB modems?

If a code change is required, would appreciate if someone could give some
leads on how to proceed.

Mayuresh