Implementing MM firmware interface

[ttuttle <ttuttle chromium org>]

Hey folks,

I'm working on 3G for Chromium OS, and I'm about to try to put
together a patch to add the firmware selection interface to
ModemManager.  I've got a few questions:

1. Should the interface definition go in introspection (presumably in
the ModemManager namespace) or new (presumably in the ModemManager1
namespace)?  I'm under the impression that new/ is not yet in use, but
we would hope to use the firmware interface fairly soon, so would
putting it in new/ delay that?

2. I'd like to get rid of the distinction between installed and
available firmwares.  The only hitch is that, if we're using a device
like the gobi3k (which stores up to 6 firmware images on the device),
selecting a firmware on disk may cause one of the firmwares on the
modem to be removed to make room, and we might not have a copy of that
firmware to reinstall if we need it again.  Personally, I am okay with
the idea that either all firmwares need to fit on the modem, or we
need to have backup copies of all firmwares the user might want to
reinstall, but I realize that might not actually apply to all use
cases.  Do people have an opinion on this?

(My gut instinct on this is that we will want to keep the distinction,
even though it makes things much more complicated.)

3. I'm not sure how much detail should go in the metadata of the
firmware image -- are we expecting to provide just enough information
that the user can pick one from a list, or enough information that a
smart client of ModemManager might be able to switch firmware
automatically to connect to a particular network?

(My gut instinct on this is that we will want enough information to
pick a particular network.)

Feedback greatly appreciated.

Thanks,

ttuttle