Hi Dmitry,

I love your patch! Yet something to improve:

[auto build test ERROR on pm/linux-next]
[also build test ERROR on linux/master linus/master v5.11-rc4 next-20210115]
[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/Dmitry-Osipenko/OPP-API-fixes-and-improvements/20210118-090646
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
config: x86_64-rhel (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/6bab64a141641bb0f56524763ef836d21bdfd73d
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Dmitry-Osipenko/OPP-API-fixes-and-improvements/20210118-090646
        git checkout 6bab64a141641bb0f56524763ef836d21bdfd73d
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

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/opp/core.c: In function 'dev_pm_opp_sync_regulators':
>> drivers/opp/core.c:2548:9: error: implicit declaration of function 'regulator_sync_voltage'; did you mean 'regulator_set_voltage'? [-Werror=implicit-function-declaration]
    2548 |   ret = regulator_sync_voltage(reg);
         |         ^~~~~~~~~~~~~~~~~~~~~~
         |         regulator_set_voltage
   cc1: some warnings being treated as errors


vim +2548 drivers/opp/core.c

  2516	
  2517	/**
  2518	 * dev_pm_opp_sync_regulators() - Sync state of voltage regulators
  2519	 * @dev:	device for which we do this operation
  2520	 *
  2521	 * Sync voltage state of the OPP table regulators.
  2522	 *
  2523	 * Return: 0 on success or a negative error value.
  2524	 */
  2525	int dev_pm_opp_sync_regulators(struct device *dev)
  2526	{
  2527		struct opp_table *opp_table;
  2528		struct regulator *reg;
  2529		int i, ret = 0;
  2530	
  2531		/* Device may not have OPP table */
  2532		opp_table = _find_opp_table(dev);
  2533		if (IS_ERR(opp_table))
  2534			return 0;
  2535	
  2536		/* Regulator may not be required for the device */
  2537		if (!opp_table->regulators)
  2538			goto put_table;
  2539	
  2540		mutex_lock(&opp_table->lock);
  2541	
  2542		/* Nothing to sync if voltage wasn't changed */
  2543		if (!opp_table->enabled)
  2544			goto unlock;
  2545	
  2546		for (i = 0; i < opp_table->regulator_count; i++) {
  2547			reg = opp_table->regulators[i];
> 2548			ret = regulator_sync_voltage(reg);

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