Re: [PATCH 2/4] backlight: add max25014atg backlight

[kernel test robot <lkp@intel.com>]

Hi Maud,

kernel test robot noticed the following build warnings:

[auto build test WARNING on d7af19298454ed155f5cf67201a70f5cf836c842]

url:    https://github.com/intel-lab-lkp/linux/commits/Maud-Spierings-via-B4-Relay/dt-bindings-backlight-Add-max25014-bindings/20250725-191221
base:   d7af19298454ed155f5cf67201a70f5cf836c842
patch link:    https://lore.kernel.org/r/20250725-max25014-v1-2-0e8cce92078e%40gocontroll.com
patch subject: [PATCH 2/4] backlight: add max25014atg backlight
config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20250727/202507270543.G0TT6f25-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250727/202507270543.G0TT6f25-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507270543.G0TT6f25-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/video/backlight/max25014.c:86:4: warning: variable 'res' is uninitialized when used here [-Wuninitialized]
      86 |                         res |= 1 << i;
         |                         ^~~
   drivers/video/backlight/max25014.c:82:13: note: initialize the variable 'res' to silence this warning
      82 |         uint8_t res, i;
         |                    ^
         |                     = '\0'
   1 warning generated.


vim +/res +86 drivers/video/backlight/max25014.c

    73	
    74	/**
    75	 * @brief get the bit mask for the DISABLE register.
    76	 *
    77	 * @param strings the led string configuration array.
    78	 * @return uint8_t bits to set in the register.
    79	 */
    80	static uint8_t strings_mask(struct max25014 *maxim)
    81	{
    82		uint8_t res, i;
    83	
    84		for (i = 0; i < 4; i++) {
    85			if (maxim->pdata->strings[i] == 0)
  > 86				res |= 1 << i;
    87		}
    88		return res;
    89	}
    90	

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