Hi 
community !
I'm lost, and need some guidance - from a GPS device !
I need some help with mmcli (ModemManager) and getting precise data from a GPS capable modem device. Looks like geoclue is getting 10m precision from wifi using some firefox api, but I need cm precision that use to be possible thanks to geoclue and ModemManager.
I have disabled wifi location provider in /etc/geoclue/geoclue.conf
# Modem GPS source configuration options
[modem-gps]
# Enable Modem-GPS source
enable=true
# WiFi source configuration options
[wifi]
# Enable WiFi source
enable=false
After restarting geoclue agent, this looks to ignore wifi provided information :
/usr/libexec/geoclue-2.0/demos/where-am-i -a 8 send me :
New location:
Latitude: 50.xxxxxx° (i hashed it !)
Longitude: 2.xxxxxxxx° (i hashed it !)
Accuracy: 20000.000000 meters (here I see that my position is not accurate as I want)
Speed: 0.000000 meters/second
Heading: 90.000000°
Timestamp: Sun 25 Apr 2021 10:52:40 PM CEST (1619383960 seconds since the Epoch)
I imagine that there is a issue with getting accurate position.
So going to mmcli, I'm running :
sudo mmcli --location-set-enable-signal -m 0
and next checking it with :
sudo mmcli --location-status -m 0
------------------------
Location | capabilities: 3gpp-lac-ci
| signals: yes
Running again /usr/libexec/geoclue-2.0/demos/where-am-i -a 8 I see that geoclue is trying to deal with mmcli :
Every 2.0s: sudo mmcli --location-status -m 023:08:51 2021
------------------------
Location | capabilities: 3gpp-lac-ci
| enabled: 3gpp-lac-ci
| signals: yes
But I don't receive any valuable data. My modem looks providing 3gpp-lac-ci protocols but gps-nmea and gps-raw (required for getting GPS data) are missing.
But my Modem is 3G capable. It is a Ericsson Lenovo H5321 gw, attached to the OS by those :
ls /dev/ttyACM*
/dev/ttyACM0 /dev/ttyACM1 /dev/ttyACM2
Sending AT*E2GPSCTL=1,5,1 and AT*E2GPSNPD initialize the GPS and start sending the GPS data :
Evermore, gpsd is able to get GPS data and evaluate location from this card with accuracy of some cm 
I'm running out of ideas ...
My setup is : Ubuntu Mate 20.04 on a Thinkpad x131e with a Lenovo Thinkpad UMTS-Module - Ericsson H5321GW
Do someone have some ideas how make geoclue to get data from gpsd or even better, to make mmcli to use my modem GPS correctly ?
Thanks in advance !