Re: [PATCH net-next] net: ethtool: allow MAC drivers to override ethtool get_ts_info

[Andrew Lunn <andrew@lunn.ch>]

On Sun, Jan 10, 2021 at 11:13:44AM +0000, Russell King wrote:
> Check whether the MAC driver has implemented the get_ts_info()
> method first, and call it if present.  If this method returns
> -EOPNOTSUPP, defer to the phylib or default implementation.
> 
> This allows network drivers such as mvpp2 to use their more accurate
> timestamping implementation than using a less accurate implementation
> in the PHY. Network drivers can opt to defer to phylib by returning
> -EOPNOTSUPP.
> 
> This change will be needed if the Marvell PHY drivers add support for
> PTP.
> 
> Note: this may cause a change for any drivers that use phylib and
> provide get_ts_info(). It is not obvious if any such cases exist.

Hi Russell

We can detect that condition through? Call both, then do a WARN() if
we are changing the order? Maybe we should do that for a couple of
cycles?

For netlink ethtool, we can also provide an additional attribute. A
MAC, or PHY indicator we can do in the core. A string for the name of
the driver would need a bigger change.

	Andrew