Re: USSD interface for ModemManager

[Marcel Holtmann <marcel holtmann org>]

Hi Dan,

> > > we would like to extend the ModemManager API so that it can handle
> > > USSD commands. The USSD API of oFono [0] looks quite nice IMHO and I'd
> > > like to propose a similar API:
> > 
> > <snip>
> > 
> > > It is basically a copy of their API (they nailed it down) except for
> > > GetProperties and PropertiesChanged signal which are ConnMan-specific.
> > > I haven't had a use-case yet for the "Respond" command (my USSD
> > > petitions are simple), but it needs to be there indeed for future
> > > uses. Thoughts?
> > 
> > any reason why you are not using oFono. It is a full telephony stack and
> > does a lot more things in the background that are mandatory. And you
> > would not have to implement the whole USSD support all by yourself.
> 
> Look, I don't go around telling people why they should be using
> NetworkManager instead of Connman or whatever.  That would just make me
> a dick.  Which is what you're being here.

I am not talking about ConnMan here at all. So no idea why you are
bringing this up.

> If you have something constructive to add to the conversation, please
> do.  Otherwise don't post, or lets start a big ofono vs. ModemManager
> thread somewhere else.

I have mentioned this before, at some point you need to start thinking
from a telephony stack point of view. Especially once you start doing
things like SMS and USSD. You have to treat your modem (even if it is a
data card) like a phone.

Maybe I phrased my question not clearly enough, but the essential part
is that you need a telephony stack. Which one, I don't care personally
that much. Or maybe you actually have plans to turn ModemManager in a
full telephony stack. Then forget that I ever mentioned oFono. But then
again, I was not asking for USSD support in the first place.

Just for fun you might wanna compare the AT init sequence of oFono with
the one from ModemManager to see what is required. There are a lot of
details in the SIM that will be needed even if you don't support voice
calls.

Regards

Marcel