Hi, I am using Jetson Nano with L4T32.7.5. I have 2 USB devices connected to the two USB jacks on Jetson Nano dev kit. There are two VIA Labs Inc USB hubs on the dev kit and one of them support “Per-port power switching” and another “Ganged power switching”.
I have learnt from the forum here that I can use the sudo uhubctl -a off command to power off the usb ports and sudo uhubctl -a on to power on back. I see in dmesg also the the USB device suspend messages comes. But there are two queries:
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The leds on the USB devices are still not off even they are suspended (as I can see in
dmesg). Is it because of point 2 mentioned in GitHub - mvp/uhubctl: uhubctl - USB hub per-port power control?
How can I confirm that if the above point is true/holds on my dev kit?
As I understand right now, the data connection is stopped but the power draw from USB ports isn’t! -
What can I do to cut off-on power draw on USB ports on the fly? Are there any other suggested methods? I can imagine a problem here about the improper device shutdown and might needs a shutdown call first on the driver level?
Thanks in advance.