Re: [PATCH] of_mdio: select fixed phy support unconditionally

[Randy Dunlap]

On 06/24/16 02:24, Arnd Bergmann wrote:
> Calling the fixed-phy functions when CONFIG_FIXED_PHY=m as a previous
> change tried cannot work if the caller is in built-in code:
> 
> drivers/of/built-in.o: In function `of_phy_register_fixed_link':
> of_reserved_mem.c:(.text+0x85e0): undefined reference to `fixed_phy_register'
> 
> Making of_mdio depend on 'FIXED_PHY || !FIXED_PHY' would solve this
> dependency by enforcing that OF_MDIO itself becomes a loadable module
> when FIXED_PHY=y, but that creates a different dependency as it
> breaks any built-in ethernet driver that uses of_mdio.
> 
> Making FIXED_PHY a bool option also cannot work, since it depends on
> PHYLIB, which again is tristate.
> 
> This version now uses 'select FIXED_PHY' to ensure that the fixed-phy
> portion of of_mdio is not optional. The main downside of this is
> a small increase in code size for cases that do not need fixed phy
> support, but it should avoid all of the link-time problems.
> 
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Fixes: d1bd330a229f ("of_mdio: Enable fixed PHY support if driver is a module")

Fixes the build errors that I was seeing.  Thanks.

Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>


> ---
>  drivers/of/Kconfig      | 1 +
>  drivers/of/of_mdio.c    | 2 --
>  include/linux/of_mdio.h | 8 ++------
>  3 files changed, 3 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
> index b3bec3aaa45d..bc07ad30c9bf 100644
> --- a/drivers/of/Kconfig
> +++ b/drivers/of/Kconfig
> @@ -74,6 +74,7 @@ config OF_NET
>  config OF_MDIO
>  	def_tristate PHYLIB
>  	depends on PHYLIB
> +	select FIXED_PHY
>  	help
>  	  OpenFirmware MDIO bus (Ethernet PHY) accessors
>  
> diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
> index de68707a99c7..e2b50bc12f23 100644
> --- a/drivers/of/of_mdio.c
> +++ b/drivers/of/of_mdio.c
> @@ -361,7 +361,6 @@ struct phy_device *of_phy_attach(struct net_device *dev,
>  }
>  EXPORT_SYMBOL(of_phy_attach);
>  
> -#if IS_ENABLED(CONFIG_FIXED_PHY)
>  /*
>   * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
>   * support two DT bindings:
> @@ -451,4 +450,3 @@ int of_phy_register_fixed_link(struct device_node *np)
>  	return -ENODEV;
>  }
>  EXPORT_SYMBOL(of_phy_register_fixed_link);
> -#endif
> diff --git a/include/linux/of_mdio.h b/include/linux/of_mdio.h
> index 6c8cb9aa4c00..4b04587d0441 100644
> --- a/include/linux/of_mdio.h
> +++ b/include/linux/of_mdio.h
> @@ -25,6 +25,8 @@ struct phy_device *of_phy_attach(struct net_device *dev,
>  
>  extern struct mii_bus *of_mdio_find_bus(struct device_node *mdio_np);
>  extern int of_mdio_parse_addr(struct device *dev, const struct device_node *np);
> +extern int of_phy_register_fixed_link(struct device_node *np);
> +extern bool of_phy_is_fixed_link(struct device_node *np);
>  
>  #else /* CONFIG_OF */
>  static inline int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
> @@ -67,12 +69,6 @@ static inline int of_mdio_parse_addr(struct device *dev,
>  {
>  	return -ENOSYS;
>  }
> -#endif /* CONFIG_OF */
> -
> -#if defined(CONFIG_OF) && IS_ENABLED(CONFIG_FIXED_PHY)
> -extern int of_phy_register_fixed_link(struct device_node *np);
> -extern bool of_phy_is_fixed_link(struct device_node *np);
> -#else
>  static inline int of_phy_register_fixed_link(struct device_node *np)
>  {
>  	return -ENOSYS;
> 


-- 
~Randy