Hi Sean, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on net-next/master] url: https://github.com/0day-ci/linux/commits/Sean-Anderson/net-phylink-Add-he... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git bb8cecf8ba127abca8ccd102207a59c55fdae515 config: hexagon-randconfig-r045-20211118 (attached as .config) 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 # https://github.com/0day-ci/linux/commit/1af77aa70fbd03602e8db3d621fdaf4e8... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Sean-Anderson/net-phylink-Add-helpers-for-c22-registers-without-MDIO/20211119-002726 git checkout 1af77aa70fbd03602e8db3d621fdaf4e8a301e98 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=hexagon If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): if (adv != -EINVAL) { ~~~ ^ ~~~~~~~ 1 warning generated. vim +2952 drivers/net/phy/phylink.c 2930 2931 /** 2932 * phylink_mii_c22_pcs_config() - configure clause 22 PCS 2933 * @pcs: a pointer to a &struct mdio_device. 2934 * @mode: link autonegotiation mode 2935 * @interface: the PHY interface mode being configured 2936 * @advertising: the ethtool advertisement mask 2937 * 2938 * Configure a Clause 22 PCS PHY with the appropriate negotiation 2939 * parameters for the @mode, @interface and @advertising parameters. 2940 * Returns negative error number on failure, zero if the advertisement 2941 * has not changed, or positive if there is a change. 2942 */ 2943 int phylink_mii_c22_pcs_config(struct mdio_device *pcs, unsigned int mode, 2944 phy_interface_t interface, 2945 const unsigned long *advertising) 2946 { 2947 bool changed = 0; 2948 u16 adv, bmcr; 2949 int ret; 2950 2951 adv = phylink_mii_c22_pcs_encode_advertisement(interface, advertising); 2953 ret = mdiobus_modify_changed(pcs->bus, pcs->addr, 2954 MII_ADVERTISE, 0xffff, adv); 2955 if (ret < 0) 2956 return ret; 2957 changed = ret; 2958 } 2959 2960 /* Ensure ISOLATE bit is disabled */ 2961 if (mode == MLO_AN_INBAND && 2962 linkmode_test_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, advertising)) 2963 bmcr = BMCR_ANENABLE; 2964 else 2965 bmcr = 0; 2966 2967 ret = mdiodev_modify(pcs, MII_BMCR, BMCR_ANENABLE | BMCR_ISOLATE, bmcr); 2968 if (ret < 0) 2969 return ret; 2970 2971 return changed; 2972 } 2973 EXPORT_SYMBOL_GPL(phylink_mii_c22_pcs_config); 2974 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org