Re: Mobile Broadband modems

[Dan Williams <dcbw redhat com>]

On Sat, 2009-02-28 at 16:50 +0000, Rick Jones wrote:
> Can someone clarify to what extent NM is supposed to detect MB modems
> "by itself", or otherwise rely on the OS (HAL etc)?

NM 0.7 asks HAL for modems.

NM 0.7.1 will use a udev prober to probe known mobile broadband driver
ttys with a series of AT commands to determine their capability.  NM
will then ask udev whether the tty has any GSM/CDMA capabilties, and if
not, fall back to asking HAL.

> I had to do some tweaking to get NM to work with the USB modem I
> purchased recently, which I kinda took as par for the course, but
> ideally this shouldn't be necessary. So I guess something is not up to
> date for this particular modem, but I'm not sure whether it's the
> default OS config (Ubuntu in my case) or NM.
> 
> The modem is a ZTE MF627, sold by "3" in the UK. It's a "zero-CD"
> device, and I had to install and configure usb_modeswitch, then add
> two udev rules to make it switch to modem mode and then modprobe
> usbserial. Finally it needed a .fdi file for HAL to make NM recognise
> it as a modem. Should NM be able to handle all this itself? If so how
> do these definitions get added?

Modeswitching should normally be done either in the kernel (because the
"Zero CD" devices make exactly Zero Sense on Linux) or in a udev rule.
After that, they can be used as a modem.  To answer your specific
question here, in NM 0.7, HAL .fdi files are used and must manually be
updated when new USB IDs are found.  NM 0.7.1 will automatically probe
the device, and hopefully find capabilities on-the-fly.

Dan