Telit FN980 support has been recently added in ModemManager and is available since version 1.14.4
It is the first Telit 5G industrial-grade M.2 form factor modem, based on Qualcomm SDX55. It is featuring sub-6 and mmWave technologies with support for LTE, WCDMA and GNSS.
Telit FN980 and ModemManager
Modem support in Linux kernel is available since kernel v5.4.
Support in ModemManager (rmnet and MBIM compositions) has been added through commits “telit: add FN980 and LM9x0 MBIM compositions rules” and “port-qmi: increase qmi_device open retries“.
Due to the modem booting time it is suggested to have also commits “telit: add initial delay for AT ports to become responsive” and “telit: add tag ID_MM_TELIT_PORT_DELAY for initial delay mechanism“, otherwise the modem serial ports are not properly recognized.
The same issue is seen with modems belonging to the LM9x0 families and the above commits fix it also for them.