Re: [PATCH net-next 8/8] net: dsa: mt7530: implement port_change_conduit op

[Daniel Golle <daniel@makrotopia.org>]

On Fri, Jun 12, 2026 at 07:36:35AM +0000, Chester A. Unal wrote:
> On 10/06/2026 20:56, Daniel Golle wrote:
> > Allow changing the CPU port affinity of user ports at runtime via
> > the IFLA_DSA_CONDUIT netlink attribute. This updates the port matrix
> > to forward to the new CPU port instead of the old one.
> > 
> > Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> 
> Fabulous!
> 
> Acked-by: Chester A. Unal <chester.a.unal@arinc9.com>
> 
> > ---
> >   drivers/net/dsa/mt7530.c | 29 +++++++++++++++++++++++++++++
> >   1 file changed, 29 insertions(+)
> > 
> > diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
> > index c96420c291d5..2f3e734b9f53 100644
> > --- a/drivers/net/dsa/mt7530.c
> > +++ b/drivers/net/dsa/mt7530.c
> > @@ -3206,6 +3206,34 @@ static int mt753x_set_mac_eee(struct dsa_switch *ds, int port,
> >   	return 0;
> >   }
> > +static int
> > +mt753x_port_change_conduit(struct dsa_switch *ds, int port,
> > +			   struct net_device *conduit,
> > +			   struct netlink_ext_ack *extack)
> > +{
> > +	struct dsa_port *new_cpu_dp = conduit->dsa_ptr;
> > +	struct dsa_port *dp = dsa_to_port(ds, port);
> > +	struct mt7530_priv *priv = ds->priv;
> > +
> > +	if (priv->id != ID_MT7531)
> > +		return -EOPNOTSUPP;
> 
> Why do we limit this to MT7531 only?

I could test it only on MT7531 (BPi R64), and that's also where it
makes most sense imho: On MT7530 we got PHY muxing, on the MMIO
switches we physically got only a single CPU port.