Hello, Looks like Peter Chen has submitted a patch that associates the USB device with the device-tree node. This is nice; we could use it to propagate the MAC address from firmware with minimal changes now, something that Arnd Bergmann suggested back in 2011 [2].
[1] USB: core: let USB device know device node https://patchwork.ozlabs.org/patch/572621/ [2] Re: RFC: Platform data for onboard USB assets https://lkml.org/lkml/2011/3/17/416 Tested to work fine on the B+ board with Peter's patch and a trivial change to u-boot so that the board code sets $ethaddr in addition to $usbethaddr for the dt fixup code. Lubo