Jetson/TX2 USB

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The Jetson TX2 Developer Kit added an INA3221 power monitoring chip to the reference carrier board for monitoring the 5V supply. Previous or custom carriers without the chip may need to manually enable USB power in the device tree to gain connectivity.

Patched DTB

You can enable USB simply by updating a file on TX2. First, download and extract the File:Tegra186-tx2-usb-base.tar.gz to your Jetson.

Then, follow the directions from Setting the DTB to boot using this new device tree, tegra186-tx2-usb-base.dtb.

Patching the DTS

If you wish to patch and re-compile your own Device Tree Source (DTS), you can do it by enabling battery_reg option in the source.

First, change the supply with battery_reg using the .dtsi file located at:


Change vbus-3-supply from vdd_usb2_5v to battery_reg. The modifications are as follows:

  pinctrl@3520000 {
     vbus-0-supply = <&vdd_usb0_5v>; 
     vbus-1-supply = <&vdd_usb1_5v>;
     vbus-2-supply = <&battery_reg>;
     - vbus-3-supply = <&vdd_usb2_5v>; 
     + vbus-3-supply = <&battery_reg>; 
     vddio-hsic-supply = <&battery_reg>;
     avdd_usb-supply = <&spmic_sd3>;
     vclamp_usb-supply = <&spmic_sd2>;
     avdd_pll_erefeut-supply = <&spmic_sd2>;

Then, regenerate the DTB and flash with the correct DTB.

Discussion Thread


USB-Lane Mapping

USB lane mapping information is in TX2 adaptation guide. To change the configuration correctly, you need to notice if plugin-manager is working or not.

[    0.142498] node /plugin-manager/fragment-500-pcie-config match with board >=3310-1000-500
[    0.142936] node /plugin-manager/fragment-500-xusb-config match with board >=3310-1000-500
[    0.143213] node /plugin-manager/fragment-500-e3325-pcie match with board >=3310-1000-500

If above plugin-manager log is shown in your dmesg, which means your device has been overwritten again by plugin-manager. Thus, the result of pcie-usb mapping may not be what you want.
Please comment out above three fragment in hardware/nvidia/platform/t18x/common/kernel-dts/t18x-common-plugin-manager/tegra186-quill-p3310-1000-a00-plugin-manager.dtsi