[PATCH net-next 2/2] dt-bindings: net: microchip,ksz: document microchip,rmii-clk-internal

From: Ante Knezic
Date: Mon Oct 16 2023 - 03:54:09 EST


On Thu, 12 Oct 2023 16:18:09 +0100, Conor Dooley wrote:
> On Thu, Oct 12, 2023 at 12:55:56PM +0200, Ante Knezic wrote:
> > Add documentation for selecting reference rmii clock on KSZ88X3 devices
> >
> > Signed-off-by: Ante Knezic <ante.knezic@xxxxxxxxxxx>
> > ---
> > .../devicetree/bindings/net/dsa/microchip,ksz.yaml | 19 +++++++++++++++++++
> > 1 file changed, 19 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
> > index 41014f5c01c4..eaa347b04db1 100644
> > --- a/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
> > +++ b/Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml
> > @@ -72,6 +72,25 @@ properties:
> > interrupts:
> > maxItems: 1
> >
> > + microchip,rmii-clk-internal:
> > + $ref: /schemas/types.yaml#/definitions/flag
> > + description:
> > + Set if the RMII reference clock is provided internally. Otherwise
> > + reference clock should be provided externally.
>
> I regret not asking this on the previous iteration - how come you need a
> custom property? In the externally provided case would there not be a
> clocks property pointing to the RMII reference clock, that would be
> absent when provided by the itnernal reference?
>
> Cheers,
> Conor.

In both cases (external and internal), the KSZ88X3 is actually providing the
RMII reference clock. Difference is only will the clock be routed as external
copper track (pin REFCLKO -> pin REFCLKI), or will it be routed internally.
So, this should not affect the clock relation between the uC and the switch
device?
This property has no effect if KSZ88X3 is not providing the reference clock.
Maybe I should provide more info in the commit message of both patches as well?