Hi Yassine, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on chanwoo-extcon/extcon-next] [also build test WARNING on robh/for-next v5.14-rc3 next-20210730] [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/Yassine-Oudjana/extcon-usbc-tusb320-Initial-TUSB320L-support/20210801-180933 base: https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/extcon.git extcon-next config: s390-randconfig-r014-20210801 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 4f71f59bf3d9914188a11d0c41bedbb339d36ff5) 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 # install s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # https://github.com/0day-ci/linux/commit/35cd3dbcb16777ecb2e3d96327b1e2d89eafc874 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Yassine-Oudjana/extcon-usbc-tusb320-Initial-TUSB320L-support/20210801-180933 git checkout 35cd3dbcb16777ecb2e3d96327b1e2d89eafc874 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=s390 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): In file included from drivers/extcon/extcon-usbc-tusb320.c:10: In file included from include/linux/i2c.h:18: In file included from include/linux/regulator/consumer.h:35: In file included from include/linux/suspend.h:5: In file included from include/linux/swap.h:9: In file included from include/linux/memcontrol.h:22: In file included from include/linux/writeback.h:14: In file included from include/linux/blk-cgroup.h:23: In file included from include/linux/blkdev.h:25: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:464:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __raw_readb(PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:477:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:36:59: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x)) ^ include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16' #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) ^ In file included from drivers/extcon/extcon-usbc-tusb320.c:10: In file included from include/linux/i2c.h:18: In file included from include/linux/regulator/consumer.h:35: In file included from include/linux/suspend.h:5: In file included from include/linux/swap.h:9: In file included from include/linux/memcontrol.h:22: In file included from include/linux/writeback.h:14: In file included from include/linux/blk-cgroup.h:23: In file included from include/linux/blkdev.h:25: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:490:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32' #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) ^ In file included from drivers/extcon/extcon-usbc-tusb320.c:10: In file included from include/linux/i2c.h:18: In file included from include/linux/regulator/consumer.h:35: In file included from include/linux/suspend.h:5: In file included from include/linux/swap.h:9: In file included from include/linux/memcontrol.h:22: In file included from include/linux/writeback.h:14: In file included from include/linux/blk-cgroup.h:23: In file included from include/linux/blkdev.h:25: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:501:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writeb(value, PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:511:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:521:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ >> drivers/extcon/extcon-usbc-tusb320.c:57:27: warning: unused variable 'tusb_modes' [-Wunused-const-variable] static const char * const tusb_modes[] = { ^ 13 warnings generated. vim +/tusb_modes +57 drivers/extcon/extcon-usbc-tusb320.c 56 > 57 static const char * const tusb_modes[] = { 58 [TUSB320_MODE_PORT] = "maintain mode set by PORT pin", 59 [TUSB320_MODE_UFP] = "upstream facing port", 60 [TUSB320_MODE_DFP] = "downstream facing port", 61 [TUSB320_MODE_DRP] = "dual role port", 62 }; 63 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org