On Fri, Sep 06, 2024 at 04:49:05PM +0200, Oleksij Rempel wrote: > Add two new properties, `forced-master` and `forced-slave`, to the > ethernet-phy binding. These properties are intended for Single Pair > Ethernet (1000/100/10Base-T1) PHYs, where each PHY and product may have > a predefined link role (master or slave). Typically, these roles are set > by hardware strap pins, but in some cases, device tree configuration is > necessary. > > Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> > --- > .../devicetree/bindings/net/ethernet-phy.yaml | 22 +++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml > index d9b62741a2259..af7a1eb6ceff6 100644 > --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml > +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml > @@ -158,6 +158,28 @@ properties: > Mark the corresponding energy efficient ethernet mode as > broken and request the ethernet to stop advertising it. > > + forced-master: > + $ref: /schemas/types.yaml#/definitions/flag > + description: > + If set, forces the PHY to operate as a master. This is used in Single Pair > + Ethernet (1000/100/10Base-T1) where each PHY and product has a predefined > + link role (master or slave). This property is board-specific, as the role > + is usually configured by strap pins but can be set through the device tree > + if needed. > + This property is mutually exclusive with 'forced-slave'; only one of them > + should be used. DT reviewers tend to complain about such mutually exclusive properties. What you are effectively adding is support for the ethtool: ethtool -s [master-slave preferred-master|preferred-slave|forced-master|forced-slave] 10Base-T1 often does not have autoneg, so preferred-master & preferred-slave make non sense in this context, but i wounder if somebody will want these later. An Ethernet switch is generally preferred-master for example, but the client is preferred-slave. Maybe make the property a string with supported values 'forced-master' and 'forced-slave', leaving it open for the other two to be added later. I've not seen the implementation yet, but i don't think there is much driver specific here. We already have phydev->master_slave_set, it just needs to be set from this property. Can it be done in phylib core somewhere? Andrew
