Hi,

I love your patch! Yet something to improve:

[auto build test ERROR on iio/togreg]
[also build test ERROR on linux/master linus/master v5.11-rc6 next-20210125]
[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/alexandru-tachici-analog-com/iio-adc-ad7124-allow-16-channels/20210204-171550
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
config: h8300-randconfig-r002-20210204 (attached as .config)
compiler: h8300-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/56f256624fcb4a920f590801074b827a00299646
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review alexandru-tachici-analog-com/iio-adc-ad7124-allow-16-channels/20210204-171550
        git checkout 56f256624fcb4a920f590801074b827a00299646
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=h8300 

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

All errors (new ones prefixed by >>):

   drivers/iio/adc/ad7124.c: In function 'ad7124_set_channel':
>> drivers/iio/adc/ad7124.c:261:17: error: 'AD_SD_SLOT_DISABLE' undeclared (first use in this function)
     261 |  if (channel == AD_SD_SLOT_DISABLE) {
         |                 ^~~~~~~~~~~~~~~~~~
   drivers/iio/adc/ad7124.c:261:17: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/iio/adc/ad7124.c:264:32: error: 'slot' undeclared (first use in this function); did you mean 'st'?
     264 |    if (st->channels[i].slot == slot)
         |                                ^~~~
         |                                st


vim +/AD_SD_SLOT_DISABLE +261 drivers/iio/adc/ad7124.c

   254	
   255	static int ad7124_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
   256	{
   257		struct ad7124_state *st = container_of(sd, struct ad7124_state, sd);
   258		unsigned int val;
   259		int i;
   260	
 > 261		if (channel == AD_SD_SLOT_DISABLE) {
   262			for (i = 0; i < AD7124_MAX_CHANNELS; i++) {
   263				/* disable channel associated with unused slot */
 > 264				if (st->channels[i].slot == slot)
   265					return ad_sd_write_reg(&st->sd, AD7124_CHANNEL(i), 2, 0);
   266			}
   267	
   268			return 0;
   269		}
   270	
   271		st->channels[channel].slot = slot;
   272		val = st->channels[channel].ain | AD7124_CHANNEL_EN(1) |
   273		      AD7124_CHANNEL_SETUP(st->channels[channel].cfg->nr);
   274	
   275		return ad_sd_write_reg(&st->sd, AD7124_CHANNEL(channel), 2, val);
   276	}
   277	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org