Hi Andy,

I love your patch! Yet something to improve:

[auto build test ERROR on staging/staging-testing]

url:    https://github.com/0day-ci/linux/commits/Andy-Shevchenko/staging-fieldbus-Use-pM-format-specifier-for-MAC-addresses/20200730-232835
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git d8a0f85d394a0cc5dec2b290ebcf8ed3cfdc1a70
config: sh-allmodconfig (attached as .config)
compiler: sh4-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
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh 

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

All error/warnings (new ones prefixed by >>):

   drivers/staging/fieldbus/anybuss/hms-profinet.c: In function 'profi_id_get':
>> drivers/staging/fieldbus/anybuss/hms-profinet.c:58:9: error: 'ETH_ALEN' undeclared (first use in this function)
      58 |  u8 mac[ETH_ALEN];
         |         ^~~~~~~~
   drivers/staging/fieldbus/anybuss/hms-profinet.c:58:9: note: each undeclared identifier is reported only once for each function it appears in
   drivers/staging/fieldbus/anybuss/hms-profinet.c:58:5: warning: unused variable 'mac' [-Wunused-variable]
      58 |  u8 mac[ETH_ALEN];
         |     ^~~
>> drivers/staging/fieldbus/anybuss/hms-profinet.c:65:1: warning: control reaches end of non-void function [-Wreturn-type]
      65 | }
         | ^

vim +/ETH_ALEN +58 drivers/staging/fieldbus/anybuss/hms-profinet.c

    53	
    54	static int profi_id_get(struct fieldbus_dev *fbdev, char *buf,
    55				size_t max_size)
    56	{
    57		struct profi_priv *priv = container_of(fbdev, struct profi_priv, fbdev);
  > 58		u8 mac[ETH_ALEN];
    59		int ret;
    60	
    61		ret = anybuss_recv_msg(priv->client, 0x0010, &mac, sizeof(mac));
    62		if (ret < 0)
    63			return ret;
    64		return snprintf(buf, max_size, "%pM\n", mac);
  > 65	}
    66	

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0-DAY CI Kernel Test Service, Intel Corporation
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