Upgrade from 1.18 to 1.21.1 causes change in behavior

Aleksander Morgado aleksandermj at chromium.org
Mon Nov 28 10:27:32 UTC 2022


Hey,

>
> I am working with an mPCI Telit LE910C4 modem connected to a Linux System on a Chip running Ubunut 20.04.
>
> With 1.18 ModemManager installed I noticed that serial ports were being listed as ignored except for a GPS port was available through a tty, this meant I couldnt issue AT commands. I also needed bit error rate from the mmlib-glib API so I decided to build ModemManager 1,21.
>
> Upon upgrading the modem no longer recognizes as a qmi device, but the AT command tty terminals are available. I was hoping for some advice on how to investigate this behavior. I did not build libqmi from source because whenever I try to compile on the device compilation freezes (overnight) on compiling certain *.o files. However, I am able to get the modem connected.
>
> Any advice on how to debug why the modem is no longer being recognized as a qmi device?

I'm a bit confused, you built MM 1.21 but you didn't build the
corresponding libqmi? If so, it looks like you built MM without QMI
support, and that is the reason why your device isn't recognized as a
QMI device.

-- 
Aleksander


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