> > --- > > Documentation/devicetree/bindings/net/ethernet-phy.yaml | 8 ++++++++ > > 1 file changed, 8 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml > > index 8fb2a6ee7e5b..349ae72ebf42 100644 > > --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml > > +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml > > @@ -93,6 +93,14 @@ properties: > > the turn around line low at end of the control phase of the > > MDIO transaction. > > > > + brr-mode: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: > > + If set, indicates the network cable interface is alternative one as > > + defined in the BroadR-Reach link mode specification under 1BR-100 and > > + 1BR-10 names. The driver needs to configure the PHY to operate in > > + BroadR-Reach mode. > > I find this second sentence unclear. Does the driver need to do > configure the phy because this mode is not enabled by default or because > the device will not work outside of this mode. BroadR-Reach uses one pair. Standard 10/100Mbps ethernet needs 2 pair, and 1G needs 4 pair. So any attempt to use standard 10/100/1G is going to fail, the socket/plug and cable just don't work for anything other than BroadR-Reach. As far as i understand it, the PHY could be strapped into BroadR-Reach mode, but there is no guarantee it is, so we should also program it to BroadR-Reach mode if this property is present. Andrew
