[PATCH net-next] net: phy: make mdio consumer / device layer a separate module

[PATCH net-next] net: phy: make mdio consumer / device layer a separate module

[Heiner Kallweit]

After having factored out the provider part from mdio_bus.c, we can
make the mdio consumer / device layer a separate module. This also
allows to remove Kconfig symbol MDIO_DEVICE.
The module init / exit functions from mdio_bus.c no longer have to be
called from phy_device.c. The link order defined in
drivers/net/phy/Makefile ensures that init / exit functions are called
in the right order.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/mdio/Kconfig     | 16 ++--------------
 drivers/net/phy/Kconfig      |  2 +-
 drivers/net/phy/Makefile     | 18 +++++-------------
 drivers/net/phy/mdio_bus.c   | 14 ++++++--------
 drivers/net/phy/phy_device.c | 11 ++---------
 include/linux/phy.h          |  3 ---
 6 files changed, 16 insertions(+), 48 deletions(-)

diff --git a/drivers/net/mdio/Kconfig b/drivers/net/mdio/Kconfig
index d3219ca19..7db40aaa0 100644
--- a/drivers/net/mdio/Kconfig
+++ b/drivers/net/mdio/Kconfig
@@ -3,21 +3,10 @@
 # MDIO Layer Configuration
 #
 
-menuconfig MDIO_DEVICE
-	tristate "MDIO bus device drivers"
-	help
-	  MDIO devices and driver infrastructure code.
-
-if MDIO_DEVICE
-
 config MDIO_BUS
-	tristate
-	default m if PHYLIB=m
-	default MDIO_DEVICE
+	tristate "MDIO bus consumer layer"
 	help
-	  This internal symbol is used for link time dependencies and it
-	  reflects whether the mdio_bus/mdio_device code is built as a
-	  loadable module or built-in.
+	  MDIO bus consumer layer
 
 if PHYLIB
 
@@ -291,4 +280,3 @@ config MDIO_BUS_MUX_MMIOREG
 
 
 endif
-endif
diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index 677d56e06..127a9fd0f 100644
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -14,7 +14,7 @@ config PHYLINK
 
 menuconfig PHYLIB
 	tristate "PHY Device support and infrastructure"
-	select MDIO_DEVICE
+	select MDIO_BUS
 	help
 	  Ethernet controllers are usually attached to PHY
 	  devices.  This option provides infrastructure for
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index 59ac3a9a3..7de69320a 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -6,27 +6,19 @@ libphy-y			:= phy.o phy-c45.o phy-core.o phy_device.o \
 				   phy_package.o phy_caps.o mdio_bus_provider.o
 mdio-bus-y			+= mdio_bus.o mdio_device.o
 
-ifdef CONFIG_MDIO_DEVICE
-obj-y				+= mdio-boardinfo.o
-endif
-
-# PHYLIB implies MDIO_DEVICE, in that case, we have a bunch of circular
-# dependencies that does not make it possible to split mdio-bus objects into a
-# dedicated loadable module, so we bundle them all together into libphy.ko
 ifdef CONFIG_PHYLIB
-libphy-y			+= $(mdio-bus-y)
-# the stubs are built-in whenever PHYLIB is built-in or module
-obj-y				+= stubs.o
-else
-obj-$(CONFIG_MDIO_DEVICE)	+= mdio-bus.o
+# built-in whenever PHYLIB is built-in or module
+obj-y				+= stubs.o mdio-boardinfo.o
 endif
-obj-$(CONFIG_PHYLIB)		+= mdio_devres.o
+
 libphy-$(CONFIG_SWPHY)		+= swphy.o
 libphy-$(CONFIG_LED_TRIGGER_PHY)	+= phy_led_triggers.o
 libphy-$(CONFIG_OPEN_ALLIANCE_HELPERS) += open_alliance_helpers.o
 
+obj-$(CONFIG_MDIO_BUS)		+= mdio-bus.o
 obj-$(CONFIG_PHYLINK)		+= phylink.o
 obj-$(CONFIG_PHYLIB)		+= libphy.o
+obj-$(CONFIG_PHYLIB)		+= mdio_devres.o
 
 obj-$(CONFIG_NETWORK_PHY_TIMESTAMPING) += mii_timestamper.o
 
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index f5ccbe33a..a6bcb0fee 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -988,7 +988,7 @@ const struct bus_type mdio_bus_type = {
 };
 EXPORT_SYMBOL(mdio_bus_type);
 
-int __init mdio_bus_init(void)
+static int __init mdio_bus_init(void)
 {
 	int ret;
 
@@ -1002,16 +1002,14 @@ int __init mdio_bus_init(void)
 	return ret;
 }
 
-#if IS_ENABLED(CONFIG_PHYLIB)
-void mdio_bus_exit(void)
+static void __exit mdio_bus_exit(void)
 {
 	class_unregister(&mdio_bus_class);
 	bus_unregister(&mdio_bus_type);
 }
-EXPORT_SYMBOL_GPL(mdio_bus_exit);
-#else
-module_init(mdio_bus_init);
-/* no module_exit, intentional */
+
+subsys_initcall(mdio_bus_init);
+module_exit(mdio_bus_exit);
+
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("MDIO bus/device layer");
-#endif
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index f85c172c4..c06a1ff9b 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -3557,19 +3557,15 @@ static int __init phy_init(void)
 	phylib_register_stubs();
 	rtnl_unlock();
 
-	rc = mdio_bus_init();
-	if (rc)
-		goto err_ethtool_phy_ops;
-
 	rc = phy_caps_init();
 	if (rc)
-		goto err_mdio_bus;
+		goto err_ethtool_phy_ops;
 
 	features_init();
 
 	rc = phy_driver_register(&genphy_c45_driver, THIS_MODULE);
 	if (rc)
-		goto err_mdio_bus;
+		goto err_ethtool_phy_ops;
 
 	rc = phy_driver_register(&genphy_driver, THIS_MODULE);
 	if (rc)
@@ -3579,8 +3575,6 @@ static int __init phy_init(void)
 
 err_c45:
 	phy_driver_unregister(&genphy_c45_driver);
-err_mdio_bus:
-	mdio_bus_exit();
 err_ethtool_phy_ops:
 	rtnl_lock();
 	phylib_unregister_stubs();
@@ -3594,7 +3588,6 @@ static void __exit phy_exit(void)
 {
 	phy_driver_unregister(&genphy_c45_driver);
 	phy_driver_unregister(&genphy_driver);
-	mdio_bus_exit();
 	rtnl_lock();
 	phylib_unregister_stubs();
 	ethtool_set_ethtool_phy_ops(NULL);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 7c29d346d..92a88b5ce 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -2033,9 +2033,6 @@ int phy_ethtool_set_link_ksettings(struct net_device *ndev,
 				   const struct ethtool_link_ksettings *cmd);
 int phy_ethtool_nway_reset(struct net_device *ndev);
 
-int __init mdio_bus_init(void);
-void mdio_bus_exit(void);
-
 int phy_ethtool_get_strings(struct phy_device *phydev, u8 *data);
 int phy_ethtool_get_sset_count(struct phy_device *phydev);
 int phy_ethtool_get_stats(struct phy_device *phydev,
-- 
2.49.0

Re: [PATCH net-next] net: phy: make mdio consumer / device layer a separate module

[Heiner Kallweit]

On 15.05.2025 07:48, Heiner Kallweit wrote:
> After having factored out the provider part from mdio_bus.c, we can
> make the mdio consumer / device layer a separate module. This also
> allows to remove Kconfig symbol MDIO_DEVICE.
> The module init / exit functions from mdio_bus.c no longer have to be
> called from phy_device.c. The link order defined in
> drivers/net/phy/Makefile ensures that init / exit functions are called
> in the right order.
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
>  drivers/net/mdio/Kconfig     | 16 ++--------------
>  drivers/net/phy/Kconfig      |  2 +-
>  drivers/net/phy/Makefile     | 18 +++++-------------
>  drivers/net/phy/mdio_bus.c   | 14 ++++++--------
>  drivers/net/phy/phy_device.c | 11 ++---------
>  include/linux/phy.h          |  3 ---
>  6 files changed, 16 insertions(+), 48 deletions(-)
> 
> diff --git a/drivers/net/mdio/Kconfig b/drivers/net/mdio/Kconfig
> index d3219ca19..7db40aaa0 100644
> --- a/drivers/net/mdio/Kconfig
> +++ b/drivers/net/mdio/Kconfig
> @@ -3,21 +3,10 @@
>  # MDIO Layer Configuration
>  #
>  
> -menuconfig MDIO_DEVICE
> -	tristate "MDIO bus device drivers"
> -	help
> -	  MDIO devices and driver infrastructure code.
> -
> -if MDIO_DEVICE
> -
>  config MDIO_BUS
> -	tristate
> -	default m if PHYLIB=m
> -	default MDIO_DEVICE
> +	tristate "MDIO bus consumer layer"
>  	help
> -	  This internal symbol is used for link time dependencies and it
> -	  reflects whether the mdio_bus/mdio_device code is built as a
> -	  loadable module or built-in.
> +	  MDIO bus consumer layer
>  
>  if PHYLIB
>  
> @@ -291,4 +280,3 @@ config MDIO_BUS_MUX_MMIOREG
>  
>  
>  endif
> -endif
> diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
> index 677d56e06..127a9fd0f 100644
> --- a/drivers/net/phy/Kconfig
> +++ b/drivers/net/phy/Kconfig
> @@ -14,7 +14,7 @@ config PHYLINK
>  
>  menuconfig PHYLIB
>  	tristate "PHY Device support and infrastructure"
> -	select MDIO_DEVICE
> +	select MDIO_BUS
>  	help
>  	  Ethernet controllers are usually attached to PHY
>  	  devices.  This option provides infrastructure for
> diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
> index 59ac3a9a3..7de69320a 100644
> --- a/drivers/net/phy/Makefile
> +++ b/drivers/net/phy/Makefile
> @@ -6,27 +6,19 @@ libphy-y			:= phy.o phy-c45.o phy-core.o phy_device.o \
>  				   phy_package.o phy_caps.o mdio_bus_provider.o
>  mdio-bus-y			+= mdio_bus.o mdio_device.o
>  
> -ifdef CONFIG_MDIO_DEVICE
> -obj-y				+= mdio-boardinfo.o
> -endif
> -
> -# PHYLIB implies MDIO_DEVICE, in that case, we have a bunch of circular
> -# dependencies that does not make it possible to split mdio-bus objects into a
> -# dedicated loadable module, so we bundle them all together into libphy.ko
>  ifdef CONFIG_PHYLIB
> -libphy-y			+= $(mdio-bus-y)
> -# the stubs are built-in whenever PHYLIB is built-in or module
> -obj-y				+= stubs.o
> -else
> -obj-$(CONFIG_MDIO_DEVICE)	+= mdio-bus.o
> +# built-in whenever PHYLIB is built-in or module
> +obj-y				+= stubs.o mdio-boardinfo.o
>  endif
> -obj-$(CONFIG_PHYLIB)		+= mdio_devres.o
> +
>  libphy-$(CONFIG_SWPHY)		+= swphy.o
>  libphy-$(CONFIG_LED_TRIGGER_PHY)	+= phy_led_triggers.o
>  libphy-$(CONFIG_OPEN_ALLIANCE_HELPERS) += open_alliance_helpers.o
>  
> +obj-$(CONFIG_MDIO_BUS)		+= mdio-bus.o
>  obj-$(CONFIG_PHYLINK)		+= phylink.o
>  obj-$(CONFIG_PHYLIB)		+= libphy.o
> +obj-$(CONFIG_PHYLIB)		+= mdio_devres.o
>  
>  obj-$(CONFIG_NETWORK_PHY_TIMESTAMPING) += mii_timestamper.o
>  
> diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
> index f5ccbe33a..a6bcb0fee 100644
> --- a/drivers/net/phy/mdio_bus.c
> +++ b/drivers/net/phy/mdio_bus.c
> @@ -988,7 +988,7 @@ const struct bus_type mdio_bus_type = {
>  };
>  EXPORT_SYMBOL(mdio_bus_type);
>  
> -int __init mdio_bus_init(void)
> +static int __init mdio_bus_init(void)
>  {
>  	int ret;
>  
> @@ -1002,16 +1002,14 @@ int __init mdio_bus_init(void)
>  	return ret;
>  }
>  
> -#if IS_ENABLED(CONFIG_PHYLIB)
> -void mdio_bus_exit(void)
> +static void __exit mdio_bus_exit(void)
>  {
>  	class_unregister(&mdio_bus_class);
>  	bus_unregister(&mdio_bus_type);
>  }
> -EXPORT_SYMBOL_GPL(mdio_bus_exit);
> -#else
> -module_init(mdio_bus_init);
> -/* no module_exit, intentional */
> +
> +subsys_initcall(mdio_bus_init);
> +module_exit(mdio_bus_exit);
> +
>  MODULE_LICENSE("GPL");
>  MODULE_DESCRIPTION("MDIO bus/device layer");
> -#endif
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index f85c172c4..c06a1ff9b 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -3557,19 +3557,15 @@ static int __init phy_init(void)
>  	phylib_register_stubs();
>  	rtnl_unlock();
>  
> -	rc = mdio_bus_init();
> -	if (rc)
> -		goto err_ethtool_phy_ops;
> -
>  	rc = phy_caps_init();
>  	if (rc)
> -		goto err_mdio_bus;
> +		goto err_ethtool_phy_ops;
>  
>  	features_init();
>  
>  	rc = phy_driver_register(&genphy_c45_driver, THIS_MODULE);
>  	if (rc)
> -		goto err_mdio_bus;
> +		goto err_ethtool_phy_ops;
>  
>  	rc = phy_driver_register(&genphy_driver, THIS_MODULE);
>  	if (rc)
> @@ -3579,8 +3575,6 @@ static int __init phy_init(void)
>  
>  err_c45:
>  	phy_driver_unregister(&genphy_c45_driver);
> -err_mdio_bus:
> -	mdio_bus_exit();
>  err_ethtool_phy_ops:
>  	rtnl_lock();
>  	phylib_unregister_stubs();
> @@ -3594,7 +3588,6 @@ static void __exit phy_exit(void)
>  {
>  	phy_driver_unregister(&genphy_c45_driver);
>  	phy_driver_unregister(&genphy_driver);
> -	mdio_bus_exit();
>  	rtnl_lock();
>  	phylib_unregister_stubs();
>  	ethtool_set_ethtool_phy_ops(NULL);
> diff --git a/include/linux/phy.h b/include/linux/phy.h
> index 7c29d346d..92a88b5ce 100644
> --- a/include/linux/phy.h
> +++ b/include/linux/phy.h
> @@ -2033,9 +2033,6 @@ int phy_ethtool_set_link_ksettings(struct net_device *ndev,
>  				   const struct ethtool_link_ksettings *cmd);
>  int phy_ethtool_nway_reset(struct net_device *ndev);
>  
> -int __init mdio_bus_init(void);
> -void mdio_bus_exit(void);
> -
>  int phy_ethtool_get_strings(struct phy_device *phydev, u8 *data);
>  int phy_ethtool_get_sset_count(struct phy_device *phydev);
>  int phy_ethtool_get_stats(struct phy_device *phydev,

Forgot to export mdio_device_bus_match.

--
pw-bot: cr

Re: [PATCH net-next] net: phy: make mdio consumer / device layer a separate module

[Jakub Kicinski]

On Thu, 15 May 2025 08:26:33 +0200 Heiner Kallweit wrote:
> >  int phy_ethtool_get_strings(struct phy_device *phydev, u8 *data);
> >  int phy_ethtool_get_sset_count(struct phy_device *phydev);
> >  int phy_ethtool_get_stats(struct phy_device *phydev,  
> 
> Forgot to export mdio_device_bus_match.

What happened to waiting 24h with the reposts..

Re: [PATCH net-next] net: phy: make mdio consumer / device layer a separate module

[Heiner Kallweit]

On 15.05.2025 15:32, Jakub Kicinski wrote:
> On Thu, 15 May 2025 08:26:33 +0200 Heiner Kallweit wrote:
>>>  int phy_ethtool_get_strings(struct phy_device *phydev, u8 *data);
>>>  int phy_ethtool_get_sset_count(struct phy_device *phydev);
>>>  int phy_ethtool_get_stats(struct phy_device *phydev,  
>>
>> Forgot to export mdio_device_bus_match.
> 
> What happened to waiting 24h with the reposts..

I wanted to provide a version for review which at least passes the
automated tests. But right, will wait also in this case.
Thanks for the hint.

Re: [PATCH net-next] net: phy: make mdio consumer / device layer a separate module

[kernel test robot]

Hi Heiner,

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/Heiner-Kallweit/net-phy-make-mdio-consumer-device-layer-a-separate-module/20250515-134852
base:   net-next/main
patch link:    https://lore.kernel.org/r/9a284c3d-73d4-402c-86ba-c82aabe9c44e%40gmail.com
patch subject: [PATCH net-next] net: phy: make mdio consumer / device layer a separate module
config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20250516/202505161753.e2B0R1Th-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250516/202505161753.e2B0R1Th-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/202505161753.e2B0R1Th-lkp@intel.com/

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "mdio_device_bus_match" [drivers/net/phy/libphy.ko] undefined!

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki