Subject: Re: Is my patch interesting for contribution: FixedPHY support for Microchip LAN743x ?

From: Andrew Lunn <[email-masked]>
Date: Sat, 21 Mar 2020 01:43:55 +0100

On Fri, Mar 20, 2020 at 02:18:14PM +0100, Roelof Berg wrote:
> Dear Kernel-Heros,
> 
> for our custom PCB I added FixedPHY support to the Microchip lan743x driver. This allows running a combination of lan7431 (MAC) and Microchip ksz9893 (switch) via a direct MII connection, i.e. without any PHYs in between. The .config determines wether (and how) FixedPHY is used, and the patch has 100%ly no (side-)effect in the default setting.
> 
> Is such a patch interesting for the community ?
> 
> Pro:
> + Supports lan7431<->kaz9893, a cost effective way of doing: PCIe<->2x-RJ45
> + Tested
> + Can be a grep-template for others with the same issue, i.e. adding FixedPHY to their driver
> 
> Con:
> - Maybe a more general approach would be better, that allows connecting any driver to a FixedPhy ? Insread of every driver doing its own thing ?

Hi Roelof

You are welcome to post it.

So far, it has been a case of each MAC driver having its own
implementation. However, if you port the MAC driver to use phylink,
not phylib, phylink will handle the fixed PHY without any additional
code.

	Andrew