Hi Darren,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on iio/togreg]
[also build test WARNING on linux/master linus/master v5.9-rc1 next-20200818]
[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/Darren-Schachter/iio-pulse-Support-PWM-capture-with-TI-AM3358-eCAP-module/20200818-233934
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
config: nios2-allyesconfig (attached as .config)
compiler: nios2-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
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=nios2

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   drivers/iio/pulse/pulse_tiecap.c: In function 'ecap_attr_prescalar_store':
>> drivers/iio/pulse/pulse_tiecap.c:193:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable]
     193 |  int ret;
         |      ^~~

# https://github.com/0day-ci/linux/commit/b454a1487cd33fe1b8962f9e6b5b0ca35b373ece
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Darren-Schachter/iio-pulse-Support-PWM-capture-with-TI-AM3358-eCAP-module/20200818-233934
git checkout b454a1487cd33fe1b8962f9e6b5b0ca35b373ece
vim +/ret +193 drivers/iio/pulse/pulse_tiecap.c

   187 
   188  static ssize_t ecap_attr_prescalar_store(struct device *dev,
   189                                          struct device_attribute *attr,
   190                                          const char *buf,
   191                                          size_t len)
   192  {
 > 193          int ret;
   194          long val;
   195          struct ecap_state *state = dev_to_ecap_state(dev); 

   196 
   197          if (test_bit(ECAP_ENABLED, &state->flags))
   198                  return -EINVAL;
   199 
   200          ret = kstrtol(buf, 16, &val);
   201          if (val > 0x05 && val != 0x1E && val != 0x1F)
   202                  return -EINVAL;
   203 
   204          mutex_lock(&state->lock);
   205          state->flags &= ~(0x1F << ECAP_PRESCALAR_OFFSET); // clear bits
   206          state->flags |= (val << ECAP_PRESCALAR_OFFSET);
   207          mutex_unlock(&state->lock);
   208 
   209          return len;
   210  }
   211 

---
0-DAY CI Kernel Test Service, Intel Corporation
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