[PATCH 1/1] net: phy: meson-gxl: Add generic dummy stubs for MMD register access

[Chris Healy]

On Sun, Jan 29, 2023 at 8:52 AM Andrew Lunn <andrew at lunn.ch> wrote:
>
> On Sat, Jan 28, 2023 at 06:26:15PM -0800, Chris Healy wrote:
> > From: Chris Healy <healych at amazon.com>
> >
> > The Meson G12A Internal PHY does not support standard IEEE MMD extended
> > register access, therefore add generic dummy stubs to fail the read and
> > write MMD calls. This is necessary to prevent the core PHY code from
> > erroneously believing that EEE is supported by this PHY even though this
> > PHY does not support EEE, as MMD register access returns all FFFFs.
>
> Hi Chris
>
> This change in itself makes sense. But i wounder if we should also
> change phy_init_eee(). It reads the EEE Ability register. The 2018
> version of the standard indicates the top two bits are reserved and
> should be zero. We also don't have any PHY which supports 100GBase-R
> through to 100Base-TX. So a read of 0xffff suggests the PHY does not
> support EEE and returning -EPROTONOSUPPORT would be good.
>
This seems like a good change to make in phy_init_eee().  I should be
able to do this.  Can this be done in a subsequent patch or does this
need to be present to land this meson specific PHY patch?

>         Andrew