Re: [PATCH net-next] net: phy: Add c45_phy_ids sysfs entry

[Andrew Lunn <andrew@lunn.ch>]

> +What:		/sys/class/mdio_bus/<bus>/<device>/c45_phy_ids
> +Date:		May 2025
> +KernelVersion:	6.16
> +Contact:	netdev@vger.kernel.org
> +Description:
> +		This attribute contains the 32-bit PHY Identifier as reported
> +		by the device during bus enumeration, encoded in hexadecimal.
> +		These C45 IDs are used to match the device with the appropriate
> +		driver.

https://docs.kernel.org/filesystems/sysfs.html#attributes

  Attributes should be ASCII text files, preferably with only one
  value per file. It is noted that it may not be efficient to contain
  only one value per file, so it is socially acceptable to express an
  array of values of the same type.

These are static values, so efficiency is not an issue.

It might be better to have a directory
/sys/class/mdio_bus/<bus>/<device>/c45_phy_ids and then for each MMD
create a file. I would also suggest using is_visible() == 0 for those
with an ID == 0.

	Andrew