USB power control on Jetson Xavier NX + carrier board reComputer J202 V1.0

Robotics & Edge Computing Jetson Systems Jetson Xavier NX
1

Hello everyone,

I have a Jetson Xavier NX Developer Kit running JetPack 5.1.1 (L4T 35.3.1), paired with the Seeed Studio reComputer J202 V1.0 carrier board.
This board uses a VIA Labs VL822-Q7 USB hub, which according to its datasheet supports Per-Port Power Switching (PPPS).

When I run lsusb -v, the hub descriptor shows the following:

Hub Descriptor:

  • bLength 9*

  • bDescriptorType 41*

  • nNbrPorts 4*

  • wHubCharacteristic 0x00e9*

  • Per-port power switching*

  • Per-port overcurrent protection*

Essentially, the hub supports power switching across ports.
However, in practice, I can’t seem to turn off the power on any of the USB ports.
I tried using uhubctl, but it had no effect.

Has anyone encountered this issue before with the VL822 on Jetson?
Is there a way to disable or restart the USB ports on this hub?
The problem may be with the firmware or version of uhubctl.

Thank you!

3

Hi,
The carrier board is from 3rdparty. We would suggest consult with the vendor and see if it is possible.

On Xavier NX developer kit, a user has shared an approach:
GitHub - obraun-sl/usb_power_cycle: Simple tool to perform a USB power cycle on Jetson Nano/NX devkit
Not sure if it works on the board and you may give it a try.

4

Do you happen to have a schematic for the original Jetson Xavier board? As I understand it, it has Realtek on it, but my board has Via Lab.
I tried to find the original schematic, but could only find the datasheet.

I would be very grateful

5

Hi,
Please check the links at download center:
Jetson Download Center | NVIDIA Developer

6

Thank you very much. I will try to figure out how to solve the problem.