Hi Andrea, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on iio/togreg] [also build test WARNING on robh/for-next linus/master v5.14-rc1 next-20210715] [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/Andrea-Merello/Add-support-for-Bosch-BNO055-IMU/20210715-222018 base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg config: arc-allyesconfig (attached as .config) compiler: arceb-elf-gcc (GCC) 10.3.0 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/616d1b9a99ec2045cdf6cc827751660a48ccc5d2 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Andrea-Merello/Add-support-for-Bosch-BNO055-IMU/20210715-222018 git checkout 616d1b9a99ec2045cdf6cc827751660a48ccc5d2 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross ARCH=arc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> drivers/iio/imu/bno055/bno055.c:250:5: warning: no previous prototype for 'bno055_calibration_load' [-Wmissing-prototypes] 250 | int bno055_calibration_load(struct bno055_priv *priv, const struct firmware *fw) | ^~~~~~~~~~~~~~~~~~~~~~~ drivers/iio/imu/bno055/bno055.c: In function '_bno055_write_raw': >> drivers/iio/imu/bno055/bno055.c:770:3: warning: this statement may fall through [-Wimplicit-fallthrough=] 770 | switch (mask) { | ^~~~~~ drivers/iio/imu/bno055/bno055.c:774:2: note: here 774 | default: | ^~~~~~~ vim +/bno055_calibration_load +250 drivers/iio/imu/bno055/bno055.c d13cfdff130569 Andrea Merello 2021-07-15 248 d13cfdff130569 Andrea Merello 2021-07-15 249 /* must be called in configuration mode */ d13cfdff130569 Andrea Merello 2021-07-15 @250 int bno055_calibration_load(struct bno055_priv *priv, const struct firmware *fw) d13cfdff130569 Andrea Merello 2021-07-15 251 { d13cfdff130569 Andrea Merello 2021-07-15 252 int i; d13cfdff130569 Andrea Merello 2021-07-15 253 unsigned int tmp; d13cfdff130569 Andrea Merello 2021-07-15 254 u8 cal[BNO055_CALDATA_LEN]; d13cfdff130569 Andrea Merello 2021-07-15 255 int read, tot_read = 0; d13cfdff130569 Andrea Merello 2021-07-15 256 int ret = 0; d13cfdff130569 Andrea Merello 2021-07-15 257 char *buf = kmalloc(fw->size + 1, GFP_KERNEL); d13cfdff130569 Andrea Merello 2021-07-15 258 d13cfdff130569 Andrea Merello 2021-07-15 259 if (!buf) d13cfdff130569 Andrea Merello 2021-07-15 260 return -ENOMEM; d13cfdff130569 Andrea Merello 2021-07-15 261 d13cfdff130569 Andrea Merello 2021-07-15 262 memcpy(buf, fw->data, fw->size); d13cfdff130569 Andrea Merello 2021-07-15 263 buf[fw->size] = '\0'; d13cfdff130569 Andrea Merello 2021-07-15 264 for (i = 0; i < BNO055_CALDATA_LEN; i++) { d13cfdff130569 Andrea Merello 2021-07-15 265 ret = sscanf(buf + tot_read, "%x%n", d13cfdff130569 Andrea Merello 2021-07-15 266 &tmp, &read); d13cfdff130569 Andrea Merello 2021-07-15 267 if (ret != 1 || tmp > 0xff) { d13cfdff130569 Andrea Merello 2021-07-15 268 ret = -EINVAL; d13cfdff130569 Andrea Merello 2021-07-15 269 goto exit; d13cfdff130569 Andrea Merello 2021-07-15 270 } d13cfdff130569 Andrea Merello 2021-07-15 271 cal[i] = tmp; d13cfdff130569 Andrea Merello 2021-07-15 272 tot_read += read; d13cfdff130569 Andrea Merello 2021-07-15 273 } d13cfdff130569 Andrea Merello 2021-07-15 274 dev_dbg(priv->dev, "loading cal data: %*ph", BNO055_CALDATA_LEN, cal); d13cfdff130569 Andrea Merello 2021-07-15 275 ret = regmap_bulk_write(priv->regmap, BNO055_CALDATA_START, d13cfdff130569 Andrea Merello 2021-07-15 276 cal, BNO055_CALDATA_LEN); d13cfdff130569 Andrea Merello 2021-07-15 277 exit: d13cfdff130569 Andrea Merello 2021-07-15 278 kfree(buf); d13cfdff130569 Andrea Merello 2021-07-15 279 return ret; d13cfdff130569 Andrea Merello 2021-07-15 280 } d13cfdff130569 Andrea Merello 2021-07-15 281 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org