USB protocol emulate Android

[hkfuertes]

Hello, first of all thank you for this amazing job!
I have a question more than an issue, forgive me if this is not the right channel. I wanted to give it a try to build the project aawireless (https://github.com/Snirpo/aawireless/tree/develop) and I manage to have them both built, aasdk and aawireless. Now the hard part is to combine everything into a RPI image.

I'm still studying the code, but for what I have found, on high level, the mechanism is very simple. TCP (via bluetooth wifi hotspot) to phone, passthrough to the USB connection, what I read from the socket is what I write to the usb and viceversa.

Basically is what the project is already doing (and also https://github.com/north3221/AAGateWayWiFi/blob/main/app/src/main/java/com/north3221/aagateway/HackerService.java).

My big conceptual question is... how can I emulate and android device? what is Android Auto HeadUnit expecting? a serial device? I can put my rpi into gadget mode, and emulate a serial device, thats not an issue... but will it work with this code:

    void App::onUSBDeviceConnected(aasdk::usb::DeviceHandle deviceHandle) {
        usbConnection = connectionFactory.create(deviceHandle);
        tryStartProxy();
    }
//...
    ConnectionFactory::create(aasdk::usb::DeviceHandle deviceHandle) {
        auto aoapDevice(aasdk::usb::AOAPDevice::create(usbWrapper, ioService, deviceHandle));
        auto transport(std::make_shared<aasdk::transport::USBTransport>(ioService, std::move(aoapDevice)));
        return create(std::move(transport));
    }

What is this deviceHandle raw usb? a serial usb?

Sorry for the abstract question, and again, thank you very much for your time!

[hkfuertes]

Oh... I just tested it with my wired phone, and this code is for the head unit itself, not for the device....