Hi JC,

I love your patch! Yet something to improve:

[auto build test ERROR on tegra/for-next]
[also build test ERROR on robh/for-next usb/usb-testing char-misc/char-misc-testing staging/staging-testing driver-core/driver-core-testing v5.10-rc1 next-20201026]
[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/JC-Kuo/Tegra-XHCI-controller-ELPG-support/20201016-211159
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux.git for-next
config: arm-defconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0
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
        # https://github.com/0day-ci/linux/commit/656fb4e32b5058dde63d15949b5ad35fbe573d4c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review JC-Kuo/Tegra-XHCI-controller-ELPG-support/20201016-211159
        git checkout 656fb4e32b5058dde63d15949b5ad35fbe573d4c
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm 

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: "xhci_get_rhub" [drivers/usb/host/xhci-tegra.ko] undefined!

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