I'm using the linux 4.14.123 kernel and once built and started in my hardware, it seem to not find the devices on the USB.
When I compare the /sys entries to the USB devices, on the working kernel, 4.4.14, and the non working 4.14.123, the /sys seem to be finding the OF configuration data, for example.
4.14.123
/sys/devices/platform/soc@ffe00000/ffe22000.usb/fsl-ehci.0/usb1
4.4.14
/sys/devices/platform/soc@ffe00000/ffe22000.usb/fsl-ehci.0/usb1
In the case of the 4.4.14 kernel, the various devices on the USB bus are found and so the entries follow.
On the 4.14.123 kernel, the are just the entries associated with the internal host controller, and nothing beyond that.