Hi Aswath, I love your patch! Perhaps something to improve: [auto build test WARNING on mkl-can-next/testing] [also build test WARNING on linux/master robh/for-next linus/master v5.12-rc7 next-20210414] [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/Aswath-Govindraju/CAN-TRANSCEIVER-Add-support-for-CAN-transceivers/20210414-220857 base: https://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next.git testing config: arm64-randconfig-r012-20210415 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 6a18cc23efad410db48a3ccfc233d215de7d4cb9) 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 arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/0day-ci/linux/commit/f0bb46b67a1f6116c84a7691e05f5059377e4640 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Aswath-Govindraju/CAN-TRANSCEIVER-Add-support-for-CAN-transceivers/20210414-220857 git checkout f0bb46b67a1f6116c84a7691e05f5059377e4640 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> drivers/phy/phy-can-transceiver.c:79:5: warning: no previous prototype for function 'can_transceiver_phy_probe' [-Wmissing-prototypes] int can_transceiver_phy_probe(struct platform_device *pdev) ^ drivers/phy/phy-can-transceiver.c:79:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int can_transceiver_phy_probe(struct platform_device *pdev) ^ static 1 warning generated. vim +/can_transceiver_phy_probe +79 drivers/phy/phy-can-transceiver.c 78 > 79 int can_transceiver_phy_probe(struct platform_device *pdev) 80 { 81 struct phy_provider *phy_provider; 82 struct device *dev = &pdev->dev; 83 struct can_transceiver_phy *can_transceiver_phy; 84 const struct can_transceiver_data *drvdata; 85 const struct of_device_id *match; 86 struct phy *phy; 87 struct gpio_desc *standby_gpio; 88 struct gpio_desc *enable_gpio; 89 u32 max_bitrate = 0; 90 91 can_transceiver_phy = devm_kzalloc(dev, sizeof(struct can_transceiver_phy), GFP_KERNEL); 92 if (!can_transceiver_phy) 93 return -ENOMEM; 94 95 match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node); 96 drvdata = match->data; 97 98 phy = devm_phy_create(dev, dev->of_node, 99 &can_transceiver_phy_ops); 100 if (IS_ERR(phy)) { 101 dev_err(dev, "failed to create can transceiver phy\n"); 102 return PTR_ERR(phy); 103 } 104 105 device_property_read_u32(dev, "max-bitrate", &max_bitrate); 106 if (!max_bitrate) 107 dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n"); 108 phy->attrs.max_link_rate = max_bitrate; 109 110 can_transceiver_phy->generic_phy = phy; 111 112 if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) { 113 standby_gpio = devm_gpiod_get(dev, "standby", GPIOD_OUT_HIGH); 114 if (IS_ERR(standby_gpio)) 115 return PTR_ERR(standby_gpio); 116 can_transceiver_phy->standby_gpio = standby_gpio; 117 } 118 119 if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) { 120 enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW); 121 if (IS_ERR(enable_gpio)) 122 return PTR_ERR(enable_gpio); 123 can_transceiver_phy->enable_gpio = enable_gpio; 124 } 125 126 phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy); 127 128 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); 129 130 return PTR_ERR_OR_ZERO(phy_provider); 131 } 132 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org