Hi "Nuno, I love your patch! Yet something to improve: [auto build test ERROR on jic23-iio/togreg] [also build test ERROR on robh/for-next linus/master v5.16 next-20220115] [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/Nuno-S/Add-support-for-LTC2688/2... base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg config: arm64-allmodconfig (https://download.01.org/0day-ci/archive/20220115/202201152138.RqRoWKHf-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 650fc40b6d8d9a5869b4fca525d5f237b0ee2803) 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 arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/0day-ci/linux/commit/d91bcc420e0c6077053e559f676fa4ae7... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Nuno-S/Add-support-for-LTC2688/20220115-172930 git checkout d91bcc420e0c6077053e559f676fa4ae76114ba5 # 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=arm64 SHELL=/bin/bash drivers/iio/dac/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): LTC2688_CHAN_EXT_INFO("toggle_en", LTC2688_CMD_TOGGLE_DITHER_EN, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/iio/dac/ltc2688.c:590:11: note: expanded from macro 'LTC2688_CHAN_EXT_INFO' .write = (_write), \ ^~~~~~~~ drivers/iio/dac/ltc2688.c:619:2: error: incompatible function pointer types initializing 'ssize_t (*)(struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'long (*)(struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') with an expression of type 'int (struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'int (struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') [-Werror,-Wincompatible-function-pointer-types] LTC2688_CHAN_EXT_INFO("toggle_en", LTC2688_CMD_TOGGLE_DITHER_EN, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/iio/dac/ltc2688.c:590:11: note: expanded from macro 'LTC2688_CHAN_EXT_INFO' .write = (_write), \ ^~~~~~~~ drivers/iio/dac/ltc2688.c:639:2: error: incompatible function pointer types initializing 'ssize_t (*)(struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'long (*)(struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') with an expression of type 'int (struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'int (struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') [-Werror,-Wincompatible-function-pointer-types] LTC2688_CHAN_EXT_INFO("dither_frequency", 0, IIO_SEPARATE, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/iio/dac/ltc2688.c:590:11: note: expanded from macro 'LTC2688_CHAN_EXT_INFO' .write = (_write), \ ^~~~~~~~ drivers/iio/dac/ltc2688.c:641:2: error: incompatible function pointer types initializing 'ssize_t (*)(struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'long (*)(struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') with an expression of type 'int (struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'int (struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') [-Werror,-Wincompatible-function-pointer-types] LTC2688_CHAN_EXT_INFO("dither_frequency_available", ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/iio/dac/ltc2688.c:590:11: note: expanded from macro 'LTC2688_CHAN_EXT_INFO' .write = (_write), \ ^~~~~~~~ drivers/iio/dac/ltc2688.c:647:2: error: incompatible function pointer types initializing 'ssize_t (*)(struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'long (*)(struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') with an expression of type 'int (struct iio_dev *, uintptr_t, const struct iio_chan_spec *, const char *, size_t)' (aka 'int (struct iio_dev *, unsigned long, const struct iio_chan_spec *, const char *, unsigned long)') [-Werror,-Wincompatible-function-pointer-types] LTC2688_CHAN_EXT_INFO("dither_en", LTC2688_CMD_TOGGLE_DITHER_EN, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/iio/dac/ltc2688.c:590:11: note: expanded from macro 'LTC2688_CHAN_EXT_INFO' .write = (_write), \ ^~~~~~~~ 5 errors generated. vim +604 drivers/iio/dac/ltc2688.c 594 595 /* 596 * For toggle mode we only expose the symbol attr (sw_toggle) in case a TGPx is 597 * not provided in dts. 598 */ 599 static const struct iio_chan_spec_ext_info ltc2688_toggle_sym_ext_info[] = { 600 LTC2688_CHAN_EXT_INFO("raw0", LTC2688_INPUT_A, IIO_SEPARATE, 601 ltc2688_dac_input_read, ltc2688_dac_input_write), 602 LTC2688_CHAN_EXT_INFO("raw1", LTC2688_INPUT_B, IIO_SEPARATE, 603 ltc2688_dac_input_read, ltc2688_dac_input_write), 605 IIO_SEPARATE, ltc2688_reg_bool_get, 606 ltc2688_dither_toggle_set), 607 LTC2688_CHAN_EXT_INFO("powerdown", LTC2688_CMD_POWERDOWN, IIO_SEPARATE, 608 ltc2688_reg_bool_get, ltc2688_reg_bool_set), 609 LTC2688_CHAN_EXT_INFO("symbol", LTC2688_CMD_SW_TOGGLE, IIO_SEPARATE, 610 ltc2688_reg_bool_get, ltc2688_reg_bool_set), 611 {} 612 }; 613 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org