Hi Jonathan, I love your patch! Perhaps something to improve: [auto build test WARNING on net-next/master] url: https://github.com/0day-ci/linux/commits/Jonathan-Lemon/ptp-ocp-Expose-various-resources-on-the-timecard/20210731-041447 base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git bc830525615df6b6b1793ac23750f32695903fd0 config: arm64-allyesconfig (attached as .config) compiler: aarch64-linux-gcc (GCC) 10.3.0 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/efb2c928bce8e0a5d32a5c3478398206e9aa26ff git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Jonathan-Lemon/ptp-ocp-Expose-various-resources-on-the-timecard/20210731-041447 git checkout efb2c928bce8e0a5d32a5c3478398206e9aa26ff # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): drivers/ptp/ptp_ocp.c: In function 'ptp_ocp_init': >> drivers/ptp/ptp_ocp.c:1600:6: warning: variable 'err' set but not used [-Wunused-but-set-variable] 1600 | int err; | ^~~ vim +/err +1600 drivers/ptp/ptp_ocp.c efb2c928bce8e0 Jonathan Lemon 2021-07-30 1596 a7e1abad13f3f0 Jonathan Lemon 2020-12-03 1597 static int __init a7e1abad13f3f0 Jonathan Lemon 2020-12-03 1598 ptp_ocp_init(void) a7e1abad13f3f0 Jonathan Lemon 2020-12-03 1599 { a7e1abad13f3f0 Jonathan Lemon 2020-12-03 @1600 int err; a7e1abad13f3f0 Jonathan Lemon 2020-12-03 1601 efb2c928bce8e0 Jonathan Lemon 2021-07-30 1602 err = bus_register_notifier(&i2c_bus_type, &ptp_ocp_i2c_notifier); efb2c928bce8e0 Jonathan Lemon 2021-07-30 1603 return pci_register_driver(&ptp_ocp_driver); a7e1abad13f3f0 Jonathan Lemon 2020-12-03 1604 } a7e1abad13f3f0 Jonathan Lemon 2020-12-03 1605 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org