Hi Maxime,

kernel test robot noticed the following build errors:

[auto build test ERROR on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Maxime-Chevallier/net-phy-phy_port-Correctly-recompute-the-port-s-linkmodes/20260127-215318
base:   net-next/main
patch link:    https://lore.kernel.org/r/20260127134202.8208-14-maxime.chevallier%40bootlin.com
patch subject: [PATCH net-next 13/13] net: ethtool: Introduce ethtool command to list ports
config: um-defconfig (https://download.01.org/0day-ci/archive/20260128/202601280753.G8XBwank-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 9b8addffa70cee5b2acc5454712d9cf78ce45710)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260128/202601280753.G8XBwank-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 [off-list ref]
| Closes: https://lore.kernel.org/oe-kbuild-all/202601280753.G8XBwank-lkp@intel.com/ (local)

All errors (new ones prefixed by >>):

   In file included from net/core/dev.c:165:

quoted

include/linux/phy_link_topology.h:110:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]

     110 | phy_link_topo_get_port(struct net_device *dev, u32 port_id)
         | ^
         | int

quoted

include/linux/phy_link_topology.h:112:9: error: incompatible pointer to integer conversion returning 'void *' from a function with result type 'int' [-Wint-conversion]

     112 |         return NULL;
         |                ^~~~
   include/linux/stddef.h:8:14: note: expanded from macro 'NULL'
       8 | #define NULL ((void *)0)
         |              ^~~~~~~~~~~
   In file included from net/core/dev.c:165:
   include/linux/phy_link_topology.h:110:1: warning: no previous prototype for function 'phy_link_topo_get_port' [-Wmissing-prototypes]
     110 | phy_link_topo_get_port(struct net_device *dev, u32 port_id)
         | ^
   include/linux/phy_link_topology.h:110:23: note: declare 'static' if the function is not intended to be used outside of this translation unit
     110 | phy_link_topo_get_port(struct net_device *dev, u32 port_id)
         |                       ^
         |                       static 
   1 warning and 2 errors generated.
--
   In file included from net/ethtool/port.c:11:

quoted

include/linux/phy_link_topology.h:110:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]

     110 | phy_link_topo_get_port(struct net_device *dev, u32 port_id)
         | ^
         | int

quoted

include/linux/phy_link_topology.h:112:9: error: incompatible pointer to integer conversion returning 'void *' from a function with result type 'int' [-Wint-conversion]

     112 |         return NULL;
         |                ^~~~
   include/linux/stddef.h:8:14: note: expanded from macro 'NULL'
       8 | #define NULL ((void *)0)
         |              ^~~~~~~~~~~
   In file included from net/ethtool/port.c:11:
   include/linux/phy_link_topology.h:110:1: warning: no previous prototype for function 'phy_link_topo_get_port' [-Wmissing-prototypes]
     110 | phy_link_topo_get_port(struct net_device *dev, u32 port_id)
         | ^
   include/linux/phy_link_topology.h:110:23: note: declare 'static' if the function is not intended to be used outside of this translation unit
     110 | phy_link_topo_get_port(struct net_device *dev, u32 port_id)
         |                       ^
         |                       static 

quoted

net/ethtool/port.c:70:7: error: incompatible integer to pointer conversion assigning to 'struct phy_port *' from 'int' [-Wint-conversion]

      70 |         port = phy_link_topo_get_port(req_info->dev, request->port_id);
         |              ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   1 warning and 3 errors generated.


vim +/int +110 include/linux/phy_link_topology.h

624ef6af11779e Maxime Chevallier 2026-01-27  109  
624ef6af11779e Maxime Chevallier 2026-01-27 @110  phy_link_topo_get_port(struct net_device *dev, u32 port_id)
624ef6af11779e Maxime Chevallier 2026-01-27  111  {
624ef6af11779e Maxime Chevallier 2026-01-27 @112  	return NULL;
624ef6af11779e Maxime Chevallier 2026-01-27  113  }
38496878690920 Maxime Chevallier 2024-08-21  114  #endif
38496878690920 Maxime Chevallier 2024-08-21  115  

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