how to mount debugfs -- where is it?

I’m trying to generate a USB test pattern, following the procedure outlined in this document
7115.UsbgeneralpageLinuxCore - Texas Instruments Wiki.pdf (360.7 KB)

It doesn’t seem to work.

Where do I find the debugfs that I"m supposed to mount? and, do I need to mount this fs in order to run the usb patterns?

I understand too that the different testmodes are under the /usb/ directory ,but, I still can’t seem to run these.

Thank you,

Our images have debugfs mounted by default.

The real issue your probably facing, both interfaces are actually active…

One being the usb-host port, the other being the usb-gadget…

You can disable usb-gadget via:

sudo systemctl disable bb-usb-gadgets.service

and reboot…

BUT based on your previous posts you are using usb-serial gadget, hence above will disable that…

So make sure to grab an external usb-serial converter. : Beagleboard:BeagleBone Black Serial -

thank you. If I want to latet reenable usb-gadget, how would I do that?

Also, do I need menuconfig? because I can’t seem to make it…

thank you

To re-enable:

sudo systemctl enable bb-usb-gadgets.service

If you want menuconfig, you don’t need it… Grab this git branch from this project that builds our shipping kernel. (do it on x86, it’s clones, so will take a few GB’s…)

git clone -b ti-linux-5.10.y
cd ./ti-linux-kernel-dev/


ok, thanks. I was finally able to get something working!
I needed to be in root and not in debian. After doing

sudo su

the command
echo "test packet" > /sys/kernel/debug/usb/musb-hdrc.1/testmode


Thank you for you help!