[PATCH net-next 2/3] net: pcs: pcs-mtk-lynxi: implement pcs_inband_caps() method

[Daniel Golle]

On Sun, Dec 08, 2024 at 09:13:11AM +0000, Russell King (Oracle) wrote:
> On Sun, Dec 08, 2024 at 03:01:38AM +0000, Daniel Golle wrote:
> > On Thu, Dec 05, 2024 at 09:42:29AM +0000, Russell King (Oracle) wrote:
> > > Report the PCS in-band capabilities to phylink for the LynxI PCS.
> > > 
> > > Signed-off-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>
> > > ---
> > >  drivers/net/pcs/pcs-mtk-lynxi.c | 16 ++++++++++++++++
> > >  1 file changed, 16 insertions(+)
> > > 
> > > diff --git a/drivers/net/pcs/pcs-mtk-lynxi.c b/drivers/net/pcs/pcs-mtk-lynxi.c
> > > index 4f63abe638c4..7de804535229 100644
> > > --- a/drivers/net/pcs/pcs-mtk-lynxi.c
> > > +++ b/drivers/net/pcs/pcs-mtk-lynxi.c
> > > @@ -88,6 +88,21 @@ static struct mtk_pcs_lynxi *pcs_to_mtk_pcs_lynxi(struct phylink_pcs *pcs)
> > >  	return container_of(pcs, struct mtk_pcs_lynxi, pcs);
> > >  }
> > >  
> > > +static unsigned int mtk_pcs_lynxi_inband_caps(struct phylink_pcs *pcs,
> > > +					      phy_interface_t interface)
> > > +{
> > > +	switch (interface) {
> > > +	case PHY_INTERFACE_MODE_1000BASEX:
> > > +	case PHY_INTERFACE_MODE_2500BASEX:
> > > +	case PHY_INTERFACE_MODE_SGMII:
> > > +	case PHY_INTERFACE_MODE_QSGMII:
> > 
> > QSGMII is not supported by this PCS.
> 
> Well...
> - lynx_pcs_get_state(), lynx_pcs_config(), and lynx_pcs_link_up()
>   include QSGMII in their case statements.
> - lynx_pcs_config_giga() refers to QSGMII in a comment, grouping it
>   with SGMII configuration.

These functions are in pcs-lynx.c and not in pcs-mtk-lynxi.c.
There is no reference to QSGMII anywhere in pcs-mtk-lynxi.c, what made
you assume it would be supported?

> 
> I think if the hardware doesn't support QSGMII, these references to it
> should be removed?
> 
> I also think that adding a .pcs_validate() method would be a good idea
> to reject interface modes that the PCS does not support.

I can add the pcs_validate function and send the patch doing that to be
included in net-next.