Programmatically switch USB ports off and on on AGX Xavier and 3rd party carrier board

[andrea]

I’m trying to programmatically switch UBS ports off and on on an AGX Xavier module mounted on a 3rd party carrier board.

I tried this approach Switch on and off usb ports programmatically on AGX - #5 by DaneLLL to no avail.

Does it depend on the carrier board design? Is there any other solution?

[WayneWWW]

Yes, it is related to board design. If their port is using system power, then it may not be able to switch on/off.

[andrea]

@WayneWWW, thanks. Is there any way to test if that’s the case? Unfortunately the carrier board’s manufacturer is not very responsive and doesn’t provide any details.

[WayneWWW]

Generally I would convert vendor’s dtb back and check which regulator they are using for vbus-supply.

If this vbus-supply is a dummy one, which is generally “battery_reg”, then it is not able to be toggled with Dane’s method above.

[andrea]

@WayneWWW from what I understand from the attached .dts file, the regulator used for the USB ports I need to reset is vdd-usb-3v3. I tried to use Dane’s method above, but it seems that I can’t disable that regulator, i.e., even if I put disabled inside the state file, nothing happens and the state file always says enabled. Am I missing something?
output.dts (355.4 KB)

[WayneWWW]

Hi andrea,

I am a little confused. Why vdd-usb-3v3? Your dts tells me you have 3 ports use 0x1e and 1 port uses 0xda

0x1e is vdd-ac-bat and 0xda is vdd-5v-sata. 0x1e is always-on power source which cannot be disabled.

		usb2-0 {
			status = "okay";
			vbus-supply = <0x1e>;
			mode = "host";
		};

		usb2-1 {
			status = "okay";
			vbus-supply = <0x1e>;
			mode = "host";
		};

		usb2-2 {
			status = "okay";
			vbus-supply = <0x1e>;
			mode = "host";
		};

		usb2-3 {
			status = "okay";
			vbus-supply = <0xda>;
			mode = "host";
		};

[andrea]

@WayneWWW ok, I guess I can’t read the dts properly. Thanks for checking it out!