The arduino snap has this declaration given to it via the store (see https://forum.snapcraft.io/t/auto-connection-request-for-arduino-raw-usb/15586):
plugs:
raw-usb:
allow-auto-connection: true
serial-port:
allow-auto-connection:
slot-snap-type:
- app
slots-per-plug: *
and when installing the snap with no hotplug serial-port devices connected, it doesn't have any serial port interfaces connected (as expected). I then connected a physical Arduino (which shows up as a serial-port via USB), and I can see the hotplug interface show up under `snap interface serial-port`, but the slot does not get connected to the hotplug serial-port interface plug on the arduino snap.
I also tried just for kicks a similar situation, but where the hotplug device is connected before installing the snap (and thus auto-connect logic on install should process when the hotplug serial-port slot exists) and it also did not automatically get connected.
Pawel, could you take a look at this? I tried to look at overlord/ifacestate to see if it was trivial to fix the not auto-connecting on install when the slot already exists, and I don't see where this is going wrong which leads me to believe that the hotplug interfaces are maybe not showing up in the auto-connect candidates at all when we process the auto-connect event?