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Select submenus for USB 3.0 controller : Device Drivers > USB support > USB support >. Select <*> for “DesignWare USB3 DRD Core Support“ and select “Gadget Only mode“ for “Deware USB3 DRD Core Support““DWC3 Mode Selection“. Note that for USB gadget precomposed configurations, there is only 1 UDC configured as a gadget. Here selecting “Gadget Only mode“ for “DesignWare USB3 DRD Core Support“ “DWC3 Mode Selection“ will configure USB3 as the serial gadget and selecting “Dual Role mode“ for “DesignWare USB3 DRD Core Support“ “DWC3 Mode Selection“ will configure USB2 as the serial gadget due to the USB2 and USB3 device drivers probed sequence.
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