Hi Kirill,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on abelloni/rtc-next]
[also build test WARNING on v5.12-rc5 next-20210326]
[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/Kirill-Kapranov/rtc-abx80x-Enable-distributed-digital-calibration/20210329-053233
base:   https://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux.git rtc-next
config: arm-randconfig-r034-20210329 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 821547cabb5819ed42245376a9afcd11cdee5ddd)
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 arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        # https://github.com/0day-ci/linux/commit/3f6d456de4f347f0d2fd0af648b1ca21b1212d17
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Kirill-Kapranov/rtc-abx80x-Enable-distributed-digital-calibration/20210329-053233
        git checkout 3f6d456de4f347f0d2fd0af648b1ca21b1212d17
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm 

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/rtc/rtc-abx80x.c:533:6: warning: variable 'retval' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
           if (reg_sqw.val < 0)
               ^~~~~~~~~~~~~~~
   drivers/rtc/rtc-abx80x.c:561:9: note: uninitialized use occurs here
           return retval;
                  ^~~~~~
   drivers/rtc/rtc-abx80x.c:533:2: note: remove the 'if' if its condition is always false
           if (reg_sqw.val < 0)
           ^~~~~~~~~~~~~~~~~~~~
   drivers/rtc/rtc-abx80x.c:530:12: note: initialize the variable 'retval' to silence this warning
           int retval;
                     ^
                      = 0
   1 warning generated.


vim +533 drivers/rtc/rtc-abx80x.c

   526	
   527	static int sqw_set(struct i2c_client *client, const char *buf)
   528	{
   529		union abx8xx_reg_sqw reg_sqw;
   530		int retval;
   531	
   532		reg_sqw.val = i2c_smbus_read_byte_data(client, ABX8XX_REG_SQW);
 > 533		if (reg_sqw.val < 0)
   534			goto err;
   535	
   536		if (sysfs_streq(buf, "none")) {
   537			reg_sqw.sqwe = 0;
   538			dev_info(&client->dev, "sqw output disabled\n");
   539		} else {
   540			int idx = __sysfs_match_string(sqfs, SQFS_COUNT, buf);
   541	
   542			if (idx < 0)
   543				return idx;
   544	
   545			if (abx80x_is_rc_mode(client) && !valid_for_rc_mode[idx])
   546				dev_warn(&client->dev, "sqw frequency %s valid only in xt mode\n",
   547					sqfs[idx]);
   548	
   549			dev_info(&client->dev, "sqw output enabled @ %s\n", sqfs[idx]);
   550			reg_sqw.sqwe = 1;
   551			reg_sqw.sqws = idx;
   552		}
   553	
   554		retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_SQW, reg_sqw.val);
   555		if (retval < 0)
   556			goto err;
   557	
   558		return 0;
   559	err:
   560		dev_err(&client->dev, "Failed to set SQW\n");
   561		return retval;
   562	

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