Modem Manager Error

Hello,

I’m with a problem when trying to connect a USB modem following these steps here:

Everything is OK until I try to start a new connection.
I have the interface wwan0 visible using ifconfig, but I get the error when trying to use the command to connect to the modem not sure why and cannot find much information about this problem in the manpage of modem manager.

torizon@verdin-imx8mm-14756371:~$ mmcli -m 0 --simple-connect="apn=emnify"
error: couldn't connect the modem: 'GDBus.Error:org.freedesktop.ModemManager1.Error.Core.NotFound: No valid data port found to launch connection
torizon@verdin-imx8mm-14756371:~$ mmcli -m 0 --simple-connect="apn=em"
error: couldn't connect the modem: 'GDBus.Error:org.freedesktop.ModemManager1.Error.Core.NotFound: No valid data port found to launch connection'
lsusb
Bus 001 Device 004: ID 0424:2740 Microchip Technology, Inc. (formerly SMSC) Hub Controller
Bus 001 Device 005: ID 2c7c:0121 Quectel Wireless Solutions Co., Ltd. EC21 LTE modem
Bus 001 Device 003: ID 067b:23a3 Prolific Technology, Inc. USB-Serial Controller
Bus 001 Device 002: ID 0424:2744 Microchip Technology, Inc. (formerly SMSC) Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Check if the necessary kernel modules for your USB modem are loaded. For Quectel modems, the qmi_wwan USB serial driver might be required. You can check loaded modules with lsmod and load a module with modprobe <module_name> .
Use mmcli -L to list modems recognized by ModemManager and ensure your modem is detected and not in a low-power or uninitialized state.
The Quectel models, can use either QMI or MBIM protocols for data connections. Use lsusb -v to inspect if the modem presents QMI or MBIM interfaces to the system. You may need specific drivers or utilities for these protocols, such as libqmi or libmbim .
Please also check this article:

Hello @alex.tx , thanks for the fast reply

Apparently all the modules seem ok

lsmod

Module                  Size  Used by
...
qmi_wwan               36864  0
...
cdc_wdm                28672  2 qmi_wwan
usbnet                 53248  1 qmi_wwan
usb_wwan               24576  1 option
...

Using mmcli -L it detects corrrectly the modem, and the modem seems to be initialized.
/org/freedesktop/ModemManager1/Modem/15 [QUALCOMM INCORPORATED] QUECTEL Mobile Broadband Module

mmcli -m 15 also the modem seems connected and not in low power

  ----------------------------------
  System   |                 device: /sys/devices/platform/soc@0/32c00000.bus/32e50000.usb/ci_hdrc.1/usb1/1-1/1-1.2
           |                drivers: qmi_wwan, option
           |                 plugin: quectel
           |           primary port: cdc-wdm0
           |                  ports: cdc-wdm0 (qmi), ttyUSB0 (qcdm), ttyUSB2 (at), ttyUSB3 (at),
           |                         wwan0 (net)
  ----------------------------------
  Status   |                   lock: sim-pin2
           |         unlock retries: sim-pin (3), sim-puk (10), sim-pin2 (3), sim-puk2 (10)
           |                  state: searching
           |            power state: on
           |         signal quality: 0% (cached)
  ----------------------------------

libqmi or libmbim also are installed, because I’ve done some tests with Quectel-CM which uses both libraries (GitHub - kmilo17pet/quectel-cm: Quectel Connect Manager tool)
This is a quectel application, is working correctly and with that application I can connect the modem perfectly without errors and can ping google from that interface with ping -I wwan0 8.8.8.8.
Only get the error when using the ModemManager mmcli, so I’m guessing this could be a bad usage or miss configuration from my side but I’ve followed the steps above regarding modem support.

Number of interfaces is 5 with lsusb -v

Bus 001 Device 009: ID 2c7c:0121 Quectel Wireless Solutions Co., Ltd. EC21 LTE modem
Device Descriptor:
...
  idVendor           0x2c7c Quectel Wireless Solutions Co., Ltd.
  idProduct          0x0121 EC21 LTE modem
...
  Configuration Descriptor:
   ...
    bNumInterfaces          5
    ...