Can't connect using ModemManager when modem is in QMI mode

[Bushman, Jeff]

I have attached the modem manager debug logs. Search for "simple connect". One odd thing I noticed was a log message about "reseting expected kernel data format to 802.3 in data interface 'wwan0'" which is not correct. The interface has always worked as raw-ip.

Here is the list of commands I sent:

  436  mmcli -L
  437  mmcli -m 0
  438  mmcli -m 0 --enable
  439  mmcli -m 0 --simple-connect='apn=broadband'
  441  mmcli -m 0 --3gpp-profile-manager-list
  442  mmcli -m 0
  443  mmcli -b 0
  444  mmcli -b 1
  445  mmcli -m 0 --reset
  446  mmcli -L
  448  mmcli -L
  449  mmcli -m 1
  450  mmcli -m 1 --enable
  451  mmcli -m 1
  452  mmcli -b 2
  454  mmcli -m 1 --bearer 2 --connect
  455  mmcli -m 1 --diable
  456  mmcli -m 1 --disable
  457  mmcli -L
  458  mmcli -m 1
  459  mmcli -m 1 --simple-status
  461  mmcli -m 1 --simple-connect='apn=broadband'
  462  mmcli -m 1
  463  mmcli -b 3
  464  mmcli -b 4

-----Original Message-----
From: Aleksander Morgado <aleksander at aleksander.es> 
Sent: Wednesday, December 1, 2021 2:15 AM
To: Bushman, Jeff <jbushman at ciena.com>
Cc: modemmanager-devel at lists.freedesktop.org
Subject: [**EXTERNAL**] Re: Can't connect using ModemManager when modem is in QMI mode

Hey Jeff,

> I'm running a Sierra Wireless MC7455 modem with SWI9X30C_02.32.11.00 r8042 CARMD-EV-FRMWR2 firmware. Using ModemManager 1.18.2 on Ubuntu 20.04.
>
> I can get the modem to connect using mmcli -m 0 --simple-connect=. when the modem is in MBIM mode.
> I can get the modem to connect using qmicli and qmi-network when the modem is in QMI mode.
>
> But when I use mmcli with ModemManager, --simple-connect fails with
>
>     error: couldn't connect the modem: 'GDBus.Error:org.freedesktop.ModemManager1.Error.Core.Cancelled: operation cancelled'
>

Oh, that is very strange.

> What is strange is that the modem seems to create a default bearer channel when it is enabled. Using simple-connect seems to create a second bearer channel which is rejected. But using -connect on the default bearer channel also fails.
>

The default bearer when enabled is the "initial EPS default bearer".
In ModemManager, this is an informative bearer object exclusively, you cannot use it to trigger a connection. When simple connect creates the new bearer, that's the one that should end up connected.

>
> Using simple connect results in two bearers.
>
> root at de-01:~# mmcli -m 1 --simple-connect='apn=broadband'
> error: couldn't connect the modem: 'GDBus.Error:org.freedesktop.ModemManager1.Error.Core.Cancelled: operation cancelled'

This is what we need to understand. Could you gather MM daemon debug logs while you attempt this simple-connect operation?
https://urldefense.com/v3/__https://modemmanager.org/docs/modemmanager/debugging/__;!!OSsGDw!fV-_YRbufvcelVcBcO6H9MctlLi6mh-ziJtAiZybF9Oa6JEUZxuRyetlFPigVA$ [modemmanager[.]org]

--
Aleksander
https://urldefense.com/v3/__https://aleksander.es__;!!OSsGDw!fV-_YRbufvcelVcBcO6H9MctlLi6mh-ziJtAiZybF9Oa6JEUZxuRyevjzE6OBQ$ [aleksander[.]es]
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: mm-debug-log_simple-connect-cancelled.txt
URL: <https://lists.freedesktop.org/archives/modemmanager-devel/attachments/20211201/dbf39d34/attachment-0001.txt>