Add support for the maxlinear,rmii-refclk-out boolean property on port
nodes to configure the RMII reference clock to be an output rather than
an input.

This property is only applicable for non-RGMII ports and allows the
switch to provide the reference clock for RMII-connected PHYs instead
of requiring an external clock source.

This corresponds to the driver changes that read this Device Tree
property to configure the RMII clock direction.

Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
 Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
index 8ccbc8942eb3..ab3ee4ecd938 100644
--- a/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
+++ b/Documentation/devicetree/bindings/net/dsa/lantiq,gswip.yaml
@@ -31,6 +31,11 @@ patternProperties:
               The delay lines adjust the MII clock vs. data timing.
               If this property is not present the delay is determined by
               the interface mode.
+          maxlinear,rmii-refclk-out:
+            type: boolean
+            description:
+              Configure the RMII reference clock to be a clock output
+              rather than an input. Only applicable for RMII mode.
 
 maintainers:
   - Hauke Mehrtens <hauke@hauke-m.de>
-- 
2.51.1