ModemManager will load:
1) The list of supported bands. Note that this doesn't mean that any possible
combination of bands is supported, as modems may support only specific
combinations, but at least gives a rough idea of what the modem is capable
of handling.
2) The list of CURRENT bands. There is no such "Allowed" bands, as we do with
modes, modems will have a specific set of bands being currently used, which
will be reported in the `Bands' property.
If the modem allows modifying the list of bands to use, this can be done with
the `SetBands()' method. If the modem doesn't support using a specific
combination of bands, this method will report an error.
We must send ATZ alone and once reply received, wait some time before sending
the next initialization commands. Otherwise, the next commands will receive
garbage as reply. The only way to handle this is to override the whole generic
initialization phase.
Make port roles more flexible. We have modems that do PPP
on interfaces other than the primary interface, and that
wasn't possible with the old code. So clean up all that
logic and move the port organization code into the core
so we can reduce code in the plugins.
In the new world order, the plugins say whether the port
is a QCDM port, an AT port, or ignored. If it's an AT
port the plugins get to tag it as primary, secondary, or
PPP, or any combination of the 3. This allows for modems
where PPP should really be done on the secondary port
(Huawei E220, Sierra devices) so that the primary port
stays open for command and status.
After all ports are grabbed by the generic classes, they get
"organized", which assigns various ports to the roles of
PRIMARY, SECONDARY, DATA, and QCDM based on specific rules
and hints that the plugin provided (which are expressed as
MMAtPortFlags).
The plugin code is responsible for determining the port
hints (ie MMAtPortFlags) at probe time, instead of having
a combination of the plugin and the modem class do the
job. This simplifies things greatly for the plugins at
the expense of more complicated logic in the core.
This is the port of commit 96505d42ed62327101dcee7c2bf31177b0bb1c9f
to the 06-api branch.
