Hi Tony, I love your patch! Perhaps something to improve: [auto build test WARNING on char-misc/char-misc-testing] [also build test WARNING on robh/for-next soc/for-next linus/master v5.16-rc5 next-20211215] [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/Tony-Huang/Add-iop-driver-for-Sunplus-SP7021/20211216-093835 base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git af40d16042d674442db8cf5fd654fabcd45fea44 config: hexagon-randconfig-r011-20211216 (https://download.01.org/0day-ci/archive/20211217/202112170208.xrabSwww-lkp@xxxxxxxxx/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project dd245bab9fbb364faa1581e4f92ba3119a872fba) 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/916d31a2d28c9f0ad7d7073d7943b9cf656038f5 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Tony-Huang/Add-iop-driver-for-Sunplus-SP7021/20211216-093835 git checkout 916d31a2d28c9f0ad7d7073d7943b9cf656038f5 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/misc/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/misc/sunplus_iop.c:475:34: warning: unused variable 'sp_iop_of_match' [-Wunused-const-variable] static const struct of_device_id sp_iop_of_match[] = { ^ 1 warning generated. vim +/sp_iop_of_match +475 drivers/misc/sunplus_iop.c 474 > 475 static const struct of_device_id sp_iop_of_match[] = { 476 { .compatible = "sunplus,sp7021-iop" }, 477 { /* sentinel */ }, 478 }; 479 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx