NetworkManager using ModemManagers simple interface limitation?

[Aleksander Morgado]

Hey,

> We're using ModemManager via NetworkManager.
> It looks like this means the "simple" interface (MMIfaceModemSimple) is used
> This causes a connection to be setup in a simple way, e.g. via
> enable (mm_base_modem_enable) and register
> (register_in_3gpp_or_cdma_network).
>
> I'd like to properly define PDP Context ID 1 (with AT+CGDCONT). The code
> to do this is there (in cid_selection_3gpp_initialize_context), but this is
> part of the "bearer" interface connect/connect_3gpp method.
>
> I wonder how to make use of the cid_selection_3gpp_initialize_context code
> somehow from NM, or if that's not possible somehow with mmcli.
>
> How do I make sure "AT+CGDCONT" is done in our case (NM + MM)?
>

None of that is right now possible, not with the Simple interface, not
with any other interface. The "CID selection" logic inside the bearer
connection logic is something done automatically and the user cannot
right now e.g. specify which specific CID must be used for the
connection.

That said, please check this MR:
https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/merge_requests/477
where a new profile management API is being suggested that allows e.g.
listing profiles or connecting using one specific profile. When that's
ready, you'd be able to modify/create a profile in a specific context
id, and then launch a connection through it. I'm working on all this
literally right now :)

-- 
Aleksander
https://aleksander.es