usb-otg mode

Hello u-booters!

I have bought a TV box (with Android). I want to install Linux on this box. Inserting sd card with Linux image did nothing.

As I did not want to break the box, I spend several days compiling u-boot with usbtty to get some insight to the TV box.
Starting the TV box with my compiled spl.bin "sunxi-fel uboot u-boot-sunxi-with-spl.bin" did not show me any usbtty on my host device and I couldn't see a thing.

Then, I discovered that I can open the TV box without breaking it. I welded USB UART to the console pins and bingo! I get console messages and can intercut with the u-boot console.

Apparently, booting the box with "sunxi-fel uboot u-boot-sunxi-with-spl.bin" Starts the box in normal usb mode. (not otg). So, the usb detach from the host machine
And the console over usbtty does not reach it.

Can we program the u-boot to start the USB in usb-otg mode?

Thank you,

Michael