Hi Christian, I love your patch! Yet something to improve: [auto build test ERROR on net-next/master] url: https://github.com/0day-ci/linux/commits/Christian-Eggers/net-ptp-introdu... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 72308ecbf33b145641aba61071be31a85ebfd92c config: sh-allmodconfig (attached as .config) compiler: sh4-linux-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/c4e4cfcabe3201e2ece90cc9025894e4e... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Christian-Eggers/net-ptp-introduce-enum-ptp_msg_type/20201118-033828 git checkout c4e4cfcabe3201e2ece90cc9025894e4ed08f069 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All error/warnings (new ones prefixed by >>): 690 | static enum ptp_msg_type tag_to_msgtype(u8 tag) | ^~~~~~~~~~~~~~ drivers/ptp/ptp_ines.c:178:11: note: previous declaration of 'tag_to_msgtype' was here 178 | static u8 tag_to_msgtype(u8 tag); | ^~~~~~~~~~~~~~ drivers/ptp/ptp_ines.c:690:26: warning: 'tag_to_msgtype' defined but not used [-Wunused-function] 690 | static enum ptp_msg_type tag_to_msgtype(u8 tag) | ^~~~~~~~~~~~~~ vim +/tag_to_msgtype +690 drivers/ptp/ptp_ines.c 689 691 { 692 switch (tag) { 693 case MESSAGE_TYPE_SYNC: 694 return PTP_MSGTYPE_SYNC; 695 case MESSAGE_TYPE_P_DELAY_REQ: 696 return PTP_MSGTYPE_PDELAY_REQ; 697 case MESSAGE_TYPE_P_DELAY_RESP: 698 return PTP_MSGTYPE_PDELAY_RESP; 699 case MESSAGE_TYPE_DELAY_REQ: 700 return PTP_MSGTYPE_DELAY_REQ; 701 } 702 return 0xf; 703 } 704 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org