Question about USB-C Polarity and Switch

#1

I have been using the Radxa Zero product, we USB3 devices. I realise the way I plug in the USB-C cable matters on Radxa zero. If i plug in one way, it shows as USB3 device, the other way shows USB2.

I looked a little further on the schematics and it has a FUSB340 USB3.1 switch, and connected to one of the GPIO pin of the CPU.

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May I know what is the intended usage of this? Do we have to manually control this GPIO pin in order to make the both polarity of plugging work as USB3? Thanks!

#2

We have written a script to automatically switch, but I forgot to integrate it into the system when I was busy. You can download it and try it out.

https://s3.setq.io/tmp/sh/usb_flip.py

#3

Originally was the driver to do this, but the driver in the mainline is not perfect, using a trick way.