Dual SIM support in Sierra EM7455/7430

[Aleksander Morgado]

Hey,

> Sierra EM7455/7430 provide support for dual SIM cards. Current sim can be found out using  AT!UIMS? at command. This will return “0” or “1” depending on which sim is active. Similarly, SIM 0 can be made active using AT!UIMS=0 and SIM 1 using AT!UIMS=1.
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> Now how to achieve this SIM switching using modemmanager? If this support is not there then what needs to be done to add this support?
>

There's no API yet to do this in MM.

Some months ago I spent some time playing with this logic in a DW5821e
but doing the SIM switching using QMI UIM commands (probably also
supported by the Sierra modules) and it didn't seem very complex to
develop this in MM. At the end we would be supporting only Dual SIM
Single Standby (one single SIM active at a time), and so the amount of
new API needed would be minimal: just a method to request the switch,
plus a property that may allow us to know whether there is another SIM
or not in advance. Patches welcome! :D

-- 
Aleksander
https://aleksander.es