Hi Matthias,

I love your patch! Yet something to improve:

[auto build test ERROR on driver-core/driver-core-testing]
[also build test ERROR on linus/master v5.12 next-20210428]
[cannot apply to usb/usb-testing robh/for-next char-misc/char-misc-testing]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Matthias-Kaehlcke/USB-misc-Add-onboard_usb_hub-driver/20210429-024426
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git acd3d28594536e9096c1ea76c5867d8a68babef6
config: x86_64-randconfig-a003-20210428 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 87fc97169e7901dfe56ca0da0d92da0c02d2ef48)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/3910d7e75c8f52afa953dbac4dc3bd4469749da8
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Matthias-Kaehlcke/USB-misc-Add-onboard_usb_hub-driver/20210429-024426
        git checkout 3910d7e75c8f52afa953dbac4dc3bd4469749da8
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "of_is_onboard_usb_hub" [drivers/usb/host/xhci-plat-hcd.ko] undefined!

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org