Hi Krzysztof,

I love your patch! Perhaps something to improve:

[auto build test WARNING on hwmon/hwmon-next]
[also build test WARNING on robh/for-next v5.14 next-20210907]
[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/Krzysztof-Adamski/Add-per-channel-properies-support-in-tmp421/20210907-214724
base:   https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next
config: mips-randconfig-c004-20210907 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 9c476172b93367d2cb88d7d3f4b1b5b456fa6020)
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 mips cross compiling tool for clang build
        # apt-get install binutils-mips-linux-gnu
        # https://github.com/0day-ci/linux/commit/50e1eb6bf222a2fb0df304033f2aaed075fd76b2
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Krzysztof-Adamski/Add-per-channel-properies-support-in-tmp421/20210907-214724
        git checkout 50e1eb6bf222a2fb0df304033f2aaed075fd76b2
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips 

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/hwmon/tmp421.c:295:6: warning: no previous prototype for function 'tmp421_probe_child_from_dt' [-Wmissing-prototypes]
   void tmp421_probe_child_from_dt(struct i2c_client *client,
        ^
   drivers/hwmon/tmp421.c:295:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void tmp421_probe_child_from_dt(struct i2c_client *client,
   ^
   static 
>> drivers/hwmon/tmp421.c:319:6: warning: no previous prototype for function 'tmp421_probe_from_dt' [-Wmissing-prototypes]
   void tmp421_probe_from_dt(struct i2c_client *client, struct tmp421_data *data)
        ^
   drivers/hwmon/tmp421.c:319:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void tmp421_probe_from_dt(struct i2c_client *client, struct tmp421_data *data)
   ^
   static 
   2 warnings generated.


vim +/tmp421_probe_child_from_dt +295 drivers/hwmon/tmp421.c

   294	
 > 295	void tmp421_probe_child_from_dt(struct i2c_client *client,
   296					struct device_node *child,
   297					struct tmp421_data *data)
   298	
   299	{
   300		struct device *dev = &client->dev;
   301		u32 i;
   302		int err;
   303	
   304		err = of_property_read_u32(child, "reg", &i);
   305		if (err) {
   306			dev_err(dev, "missing reg property of %pOFn\n", child);
   307			return;
   308		} else if (i > MAX_CHANNELS) {
   309			dev_err(dev, "invalid reg %d of %pOFn\n", i, child);
   310			return;
   311		}
   312	
   313		of_property_read_string(child, "label", &data->channel[i].label);
   314		if (data->channel[i].label)
   315			data->temp_config[i] |= HWMON_T_LABEL;
   316	
   317	}
   318	
 > 319	void tmp421_probe_from_dt(struct i2c_client *client, struct tmp421_data *data)
   320	{
   321		struct device *dev = &client->dev;
   322		const struct device_node *np = dev->of_node;
   323		struct device_node *child;
   324	
   325		for_each_child_of_node(np, child) {
   326			tmp421_probe_child_from_dt(client, child, data);
   327		}
   328	}
   329	

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