ModemManager and ppp

[Martin MOKREJŠ]

Aleksander Morgado wrote:
> On Fri, Mar 10, 2017 at 5:24 PM, Tom Hayward <tom at harbortronics.com> wrote:
>> Is this a matter of configuration, lack of support, or simply outside
>> the scope of ModemManager? Is there a way to use ModemManager to
>> initiate the ppp connection?
> 
> Initiating a ppp session is currently out of scope of MM. MM will put
> the TTY in connected mode; then you need to (externally, another app)
> launch pppd on the TTY that MM reported as "connected".
> 
> The whole MM sequence is the same for TTY-only and QMI/MBIM+wwan
> devices; just launch --simple-connect, if successful it creates a
> bearer object that is in connected state. The bearer object will
> report which is the data interface to use (which could be a wwan, or a
> TTY) and also which method to use (ppp over the tty, or DHCP or Static
> IP config over the wwan). An application that wants to use MM as modem
> management and handle multiple modem types needs to handle all 3
> methods and use explicitly the one reported by MM (e.g. some modems
> won't be able to use DHCP over a wwan and in that case static IP
> setting needs to be performed).

This should go into ModemManager manual page plus the follow-ups translating
CLOCAL into CRT/RTS wording and AT commands people may try to include in
their ppp config files.

Martin