Huawei E220 + Data Connection Manager

[Marcel Holtmann]

Hi Mitsutaka,

> I'm trying to implement for Huawei E220 using Data Connection
> Manager. I understand GPRS data conneciton is working in progress. But
> I don't know much connection sequence that.
> 
> So I'd like to tell me how should I approach. and I guess data
> connection in the following. If I mistake, please point out.
> 
> 1. Launch ofonod, plug-in the modem.
> 2. Enable modems for getting modem information, Model, Manufacture, Serial and so on(test/enable-modem).
> 
> 3. Create a context(org.ofono.PrimaryDataContext) according to doc/dataconnectionmanager-api.txt 
>    ex. Japanese carrier
> % ./test/list-contexts
> [ /huawei1 ]
>     [ /huawei1/primarycontext1 ]
>         Username = em
>         Name = Example
>         Settings = { }
>         Active = 0
>         AccessPointName = 1
>         Password = em
>         Type = internet
> 
> 4. Activate it. but currently it can not be atacched
> Traceback (most recent call last):
>   File "./test/activate-context", line 38, in <module>
>     context.SetProperty("Active", dbus.Boolean(1))
>   File "/usr/lib/python2.6/site-packages/dbus/proxies.py", line 68, in __call__
>     return self._proxy_method(*args, **keywords)
>   File "/usr/lib/python2.6/site-packages/dbus/proxies.py", line 140, in __call__
>     **keywords)
>   File "/usr/lib/python2.6/site-packages/dbus/connection.py", line 622, in call_blocking
>     message, timeout)
> dbus.exceptions.DBusException: org.ofono.Error.NotAttached: GPRS is not attached
> 
> 5. Dialup using ATDT (this case is support only Tone)
>    ATDT*99***1#
>    CONNECT
> 6. ppp0 interface up
> 7. Authenticate EAP, PAP or CHAP using Username, Passowrd
> 8. Getting IP Address, Netmask, Gateway from APN(?)

so this is the interesting part. We don't wanna use the magic *99* magic
and actually use the proper GPRS AT command for connecting the context.
But then we have to talk PPP. That is currently work in progress as an
extension to GAtChat.

Regards

Marcel