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Cannot power off the USB device

co flag

I'm using Ubuntu 20.04 on Jetson Nano dev kit and a USB camera. The problem is that the camera isn't loaded to /dev/video0 if I reboot the pc. So I have to physically unplug and re-plug in to make it work properly again.

It seems like the system only knows something is on the USB port where the camera was connected to before reboot, but doesn't know what it is.

To avoid this issue the camera must turn off before the pc's boot up process.

lsusb shows nothing on the port. uhubctl shows "connect []" on the port, compared to nothing if nothing is connected

Screenshot 1

I attached what dmesg shows after booting up

Screenshot 2

So I've tried methods that were introduced as how to disable or power off the USB ports/devices such as using uhubctl, unbinding/binding, setting 0 for flags like /power/control, /power/pm_qos_no_power_off, /authorized, etc., under /sys/bus/usb/devices/<device_name>

But the light on the USB camera never turn off.

Please tell me if anyone has had same issue and solved it.

mvp avatar
id flag
mvp
uhubctl author here. Make sure you use version 2.4.0 or later. However, if your hardware doesn't support power switching, nothing else will be able to turn it off.
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