Can you switch the usb2-companion for the USB 3.0 port? Or is there a hardware requirement
on the Jetson modules (NX and Nano) that requires a specific USB 2.0 companion port?
I have a custom carrier board with only one USB Type A connector and one USB Type C connector.
I’m wanting to switch the “forced recovery” usb connection from the USB 2.0 Type A connector over to
the USB 3.0 Type C connector.
What if I switch the USB 2.0 ports (USB1 and USB0) on my custom carrier board?
So USB1 (SODIM D-/D+ Pins #115/#117) would no longer be the USB 3.0 companion port, but instead
connect to the USB Type A 2.0 host connector (no longer OTG). USB0 (SODIM D-/D+ pins #109/#111) will be
the new USB 3.0 companion port wired to the Type C connector (now becoming OTG).
Will this work? Can any usb 2.0 port be used as the 3.0 companion port?
Once I make the hardware change, the only device tree change I think I need is
in tegra194-p3668-common.dtsi, changing the nvidia,usb2-companion port to usb2-0 instead of usb2-1.
Hardware changes will involve moving usb2-0 to the Type C connector, becoming the new 3.0 companion port, and staying OTG in device tree. usb2-1 will be moved to the Type A connector and will stay set to “host” mode in device tree.
ports {
usb2-0 {
mode = “otg”;
status = “okay”;
};
usb2-1 {
mode = “host”;
status = “okay”;
};
usb2-2 {
mode = “host”;
vbus-supply = <&battery_reg>;
status = “okay”;
};
usb3-2 {
- nvidia,usb2-companion = <1>;
+ nvidia,usb2-companion = <0>;
status = “okay”;
};
};
Does this sound right?