ModemManager and modems discovery in OpenWRt

[Enrico Mioso]

Hello guys!
Aleksander and Bjørn, I am CC'ing you since this question came up reading your discussion about udev rules usage.

So, modems discovery mechanism in ModemManager is implemented via --report-kernel-event.
And we have --report-kernel-event-auto-scan as well.

the current method of reporting even tough, is not as robust: and sometimes it may happen a modem is present but not detected.
With all the respect, while --report-kernel-event seems to be a very good decision / design choice, I don't like as much the current hotplug--based method / scripts we use to report for modem events.
The cache, and all that, they seem too fragile to me. What's your opinion on that?
I would be set out to replace that, maybe implementing some code to listen to netlink events and directly "inject" events in MM, or something like that.
I would like to have your opinion on that, and directions on the best way to proceed.

Enrico