This guide was tested on the Redmi Note 5A Lite (Ugglite) and works very well for SMS and voice calls (which only work over 2G/3G and do not support voice) and mobile internet *.
As this uses a Qualcomm SoC, we need to use a Qualcomm IPC Router (QRTR) to communicate with the modem. In order for ModemManager to recognise our modem, we need to open a data port mapping (DPM) entry via the QRTR transport.
To do this, run the following command:
sudo qmicli -d qrtr://0 --dpm-open-port="hw-data-ep-type=bam-dmux,hw-data-ep-iface-number=0,hw-data-rx-id=1,hw-data-tx-id=1"After that, you can restart the ModemManager service and wait for ModemManager to recognise our modem.
For more information on using the modem, you can read this section of the PostmarketOS wiki *
Troubleshooting
Some carriers' APNs are not in the database. In this case, you may receive an error message when trying to activate mobile data
Error: Connection activation failed: Failed to select the specified APN.
Hint: Use 'journalctl -xe NM_CONNECTION=25abfd08-9127-442a-abc8-9bc8513bf0f8 + NM_DEVICE=qrtr0' to get more details.'To resolve this issue, you will need to add the APN manually.
For example, I use the Indonesian carrier Telkomsel. To do this, run the following commands:
sudo nmcli con modify "modem" gsm.auto-config no
sudo nmcli con modify "modem" gsm.apn "internet"After setting the APN, you can activate mobile data by running the following command:
sudo nmcli con up "modem"