Detecting SIM REFRESH events

[Teijo Kinnunen]

Hi again,

On 5.8.2020 19.54, Aleksander Morgado wrote:

 >> ...
>>
>> The underlying motivation here is that eSIM cards are increasingly being
>> used in IoT applications and as Linux is an important IoT SW platform,
>> we'd like them to work as smoothly as possible there. There remains
>> other work to be done, but getting profile switches to work as fluently
>> as possible would be a good starting point.
>>
> 
> This all looks good to me, an eSIM profile switch should be to MM's
> eyes like a SIM hotswap or a SIM slot change.
> 
> If you're planning to work on this please base your work on top of the
> following MR, which introduces multi-SIM support for QMI devices (so
> that you don't get too many conflicts if this MR gets in before you
> finish): https://gitlab.freedesktop.org/mobile-broadband/ModemManager/-/merge_requests/330

I've started work on this, with the first libqmi changes made (more 
shall follow). Primarily I've tested it with Quectel EG25 (which is
MDM9207 based) so far, and I'm getting refresh events as expected
when changing profiles on an eUICC.

I figured out that there might be another way to detect the switches,
which is listening to PHYSICAL_SLOT_STATUS events. This has a bit
higher abstraction level, so it would probably be preferable if
supported. But at least those MDM9206 and MDM9207 based modems I
tested (Quectel EG25 and BG96) don't support slot status, so the
refresh registration way would be needed as fallback anyway.

Any ideas which modems do actually support QMI slot status? I
would like to try if slot status changes could also be used for this
purpose.

BR.

- Teijo