Re: [RESEND PATCH net-next v2] net: phylink: Add helpers for c22 registers without MDIO

[Sean Anderson]

On 11/18/21 4:07 PM, kernel test robot wrote:
> 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-helpers-for-c22-registers-without-MDIO/20211119-002726
> 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/1af77aa70fbd03602e8db3d621fdaf4e8a301e98
>          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@xxxxxxxxx>
>
> All warnings (new ones prefixed by >>):
>
> > > drivers/net/phy/phylink.c:2952:10: warning: result of comparison of constant -22 with expression of type 'u16' (aka 'unsigned short') is always true [-Wtautological-constant-out-of-range-compare]
>             if (adv != -EINVAL) {
>                 ~~~ ^  ~~~~~~~
>     1 warning generated.

Hmm, looks like this should be

	ret = phylink_mii_c22_pcs_encode_advertisement();
	if (ret > 0) {
		...
	}

and just eliminate adv

--Sean

> 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);
> > 2952		if (adv != -EINVAL) {
>    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@xxxxxxxxxxxx