Access module connected to CM4

[saeedjohar]

Hello,

We have LTE modules connected to the CM4 over USB. Is it possible to access the LTE module to get the IMEI of the module during provisioning?

Thanks

[maxnet]

Not out-of-the-box.

Would need to recompile the Linux kernel used with the kernel module that your LTE module uses (probably a matter of adding CONFIG_USB_ACM=y to the config).
And a couple lines of shell script to send AT+GSN or a similar AT command (depending on exact LTE module) to it, and read back the IMEI.

And some more changes if you want to use that IMEI anywhere in the system (e.g. if you want it in the database or on a label, etc.)

[saeedjohar]

Okay then, I will look into Kernel modification and recompiling the kernel of the provisioner.
For the time being, I have a script that runs once when the device boots up for the first time and sends the mentioned data to a local server.

[maxnet]

Added support for a couple common serial devices to the kernel configuration of scriptexecutor ( raspberrypi/scriptexecutor@8047f15 ) bundled in the latest cmprovision.
You may want to try if your device is now recognized as well.

Closing this for now.

[saeedjohar]

Hello @maxnet,

Thank you for updating here.
I have successfully tested this with CM4 IO carrier board but failed to load the USB on our two custom boards.
The difference between these boards are; one of the custom boards uses LAN9514 as USB hub while the other uses TUSB4020BI.

Do I need to alter anything on the scriptexecutor?

Thank you

[maxnet]

Don't think the USB HUB itself should matter, as I think they all speak the USB HUB class protocol thing.
But if something else is broken, e.g. the lines used for USB OTG negotiation, you may need another line in /var/lib/cmprovision/scriptexecute/config.txt
E.g. instead of "dtoverlay=dwc2" (USB OTG), force host mode with: "dtoverlay=dwc2,dr_mode=host"
Or remove line and use the XHCI alternative with "otg_mode=1"

[saeedjohar]

Adding dr_mode=host did the trick.

Thank you