hal_input and USB

I have been trying to connect my Arduino controlled pendant to LinuxCNC using hal_input via the USB Arduino interface, with little success.
The documentation shows  loadusr hal_input inputspec where the input spec is the details of the relevant USB interface gathered from /proc/bus/input/devices.
My Arduino connects to the USB and I can see it with lsusb.  However it is not present in /proc/bus/input/devices, but is present in /sys/kernel/debug/usb/devices.

If I run hal from the terminal and then try to load hal_input it complains it cannot find the Arduino and gives me a list of the devices in /proc/bus/input/devices.

Am I missing something?

I am running LinuxCNC version 2.9 on Debian Buster.

Did you try adding permissions and adding your user name to the "dialout" group?
This is something i had to deal with any time i used an arduino with Linux.

Thanks tommylight. There is indeed a problem with the permissions, but I don't think that is the root of the matter. Doing halrun from the command line as sudo gets past the permissions but I am still getting the issue I reported above. Running as a normal user indicates there is a permissions problem.
I found this ' wiki.debian.org/HowToIdentifyADevice/USB '.
The last section seems to indicate that there has been a change to how usb is accessed. This seems to fit in with what I have found. My Ubuntu desktop also seems to have the same arrangement.
Obviously I need to fix the permissions but there seems to be something else amiss here.
Don