Re: [PATCH v2 4/4] net: phy: realtek: add RTL8224 polarity support

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

Hi Damien,

kernel test robot noticed the following build warnings:

[auto build test WARNING on 983d014aafb14ee5e4915465bf8948e8f3a723b5]

url:    https://github.com/intel-lab-lkp/linux/commits/Damien-Dejean/net-phy-realtek-add-RTL8224-pair-order-support/20260122-000009
base:   983d014aafb14ee5e4915465bf8948e8f3a723b5
patch link:    https://lore.kernel.org/r/20260121151506.813783-4-dam.dejean%40gmail.com
patch subject: [PATCH v2 4/4] net: phy: realtek: add RTL8224 polarity support
config: x86_64-defconfig (https://download.01.org/0day-ci/archive/20260123/202601230608.52Hf4Qza-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260123/202601230608.52Hf4Qza-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/202601230608.52Hf4Qza-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In function 'rtl8224_mdi_config_polarity',
       inlined from 'rtl8224_config_init' at drivers/net/phy/realtek/realtek_main.c:1761:9:
>> drivers/net/phy/realtek/realtek_main.c:1739:12: warning: 'polarity' is used uninitialized [-Wuninitialized]
    1739 |         if (polarity & ~0xf)
         |            ^
   drivers/net/phy/realtek/realtek_main.c:1727:13: note: 'polarity' was declared here
    1727 |         u32 polarity, val;
         |             ^~~~~~~~


vim +/polarity +1739 drivers/net/phy/realtek/realtek_main.c

  1722	
  1723	static int rtl8224_mdi_config_polarity(struct phy_device *phydev)
  1724	{
  1725		struct device_node *np = phydev->mdio.dev.of_node;
  1726		u8 port_offset = phydev->mdio.addr & 3;
  1727		u32 polarity, val;
  1728		int ret;
  1729	
  1730		ret = of_property_read_u32(np, "realtek,mdi-cfg-polarity", &polarity);
  1731	
  1732		/* Do nothing if the property is not present */
  1733		if (ret == -EINVAL)
  1734			return 0;
  1735	
  1736		if (!ret)
  1737			return ret;
  1738	
> 1739		if (polarity & ~0xf)
  1740			return -EINVAL;
  1741	
  1742		val = __phy_package_read_mmd(phydev, 0, MDIO_MMD_VEND1,
  1743					     RTL8224_VND1_MDI_POLARITY_SWAP);
  1744		if (val < 0)
  1745			return val;
  1746	
  1747		val &= ~(0xf << port_offset);
  1748		val |= polarity << port_offset;
  1749		return __phy_package_write_mmd(phydev, 0, MDIO_MMD_VEND1,
  1750					       RTL8224_VND1_MDI_POLARITY_SWAP, val);
  1751	}
  1752	

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