Hi Daniel, I love your patch! Perhaps something to improve: [auto build test WARNING on media-tree/master] [also build test WARNING on v5.16-rc5] [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/Daniel-Scally/Introduce-ancillar... base: git://linuxtv.org/media_tree.git master config: i386-buildonly-randconfig-r003-20211213 (https://download.01.org/0day-ci/archive/20211214/202112141239.xdqTNOOD-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project b6a2ddb6c8ac29412b1361810972e15221fa021c) 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/627c8446267d301ed36953f7e4fa616ab... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Daniel-Scally/Introduce-ancillary-links/20211214-073020 git checkout 627c8446267d301ed36953f7e4fa616ab6cb771a # 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=i386 SHELL=/bin/bash drivers/media/mc/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): void media_remove_ancillary_link(struct media_link *link) ^ drivers/media/mc/mc-entity.c:1062:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void media_remove_ancillary_link(struct media_link *link) ^ static drivers/media/mc/mc-entity.c:17:27: warning: unused function 'intf_type' [-Wunused-function] static inline const char *intf_type(struct media_interface *intf) ^ 2 warnings generated. vim +/media_remove_ancillary_link +1062 drivers/media/mc/mc-entity.c 1061 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org