Serial not functioning in BalenaOS, ch341-uart (module usbserial not found)

Product support balenaOS
39

cool, so it looks like the device has been found by the operating system and USB serial has been configured. can you communicate with the GPS over /dev/ttyUSB0?

41

No, that’s the weird part. It doesn’t mount to any /dev path which led me down a rabbit hole (and eventually to this thread). I read that it’s possible to fix this by manually initiating an attachment through modprobe usbserial vendor=0x067b product=0x2303 . Source: https://www.fir3net.com/UNIX/Linux/how-do-i-connect-to-a-serial-device-using-a-usb-to-serial-convertor-in-linux.html

But I get the message “usbserial” does not exist.

42

Yeah, you get this because the usbserial module is compiled in to the kernel. It’s definitely detecting your device. Do you mean you can’t see new devices in /dev on the host OS or inside your service container?

44

@jimsynz I can’t detect it on the host OS (and therefore the service container). I agree that it’s definitely detecting the USB - it’s just that I don’t get the “now attached to /dev/ttyUSB0” message which is super frustrating :frowning: You can see that message in @matthewcroughan’s expected dmesg output above.

I’ll try to do some more digging online.

46

Here are the udev rules getting triggered:

KERNEL[57.697712] add      /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2 (usb)
KERNEL[57.763549] add      /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2/3-1.2:1.0 (usb)
KERNEL[57.764108] bind     /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2 (usb)
UDEV  [57.791567] add      /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2 (usb)
UDEV  [57.799216] add      /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2 (usb)
UDEV  [57.802103] add      /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2/3-1.2:1.0 (usb)
UDEV  [57.803500] add      /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2/3-1.2:1.0 (usb)
UDEV  [57.806846] bind     /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2 (usb)
UDEV  [57.811178] bind     /devices/platform/soc/soc:usb3-0/12000000.dwc3/xhci-hcd.3.auto/usb3/3-1/3-1.2 (usb)
47

What is the output of the following command in the host OS?

zcat /proc/config.gz | grep -i USB_SERIAL_PL

48

in fact, would like to see more generic output as well

zcat /proc/config.gz | grep -i USB_SERIA

49

Hi @zubairlk, thanks for joining in.

In the service container:
# CONFIG_USB_SERIAL is not set

I’m having issues getting to the host OS right now so I’ll post that when I can get a terminal session.

50

Same thing in host: # CONFIG_USB_SERIAL is not set

51

There is a PR in meta-balena for these drivers for all devices

Step 1 will be meta-balena release
Step 2 will be an odroid-xu4 release
Can’t say much about time-frames…

52

Ok no worries, I’ll check in on the PR / releases every so often. Just glad I wasn’t going crazy.

Thanks!

55

Hi @transportation

Just wanted to let you know that the fix related to CONFIG_USB_SERIAL that has been discussed in this thread has been applied in our meta-balena repository, and I’ve created an internal note for our team to notify you when the new release for ODroid XU4 containing this fix is available in production.

Kind regards
Alida

58

Awesome, thank you @AlidaOdendaal!