From: Rafał Miłecki <rafal@milecki.pl>

Some network devices (e.g. access points) come with BCM54210E PHY that
requires being set into master mode to work properly.

Add binding for BCM54210E as found in Luxul AP devices (600d:84a6) and
the "brcm,master-mode" property.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
 .../devicetree/bindings/net/brcm,bcm54xx.yaml | 37 +++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/brcm,bcm54xx.yaml

diff --git a/Documentation/devicetree/bindings/net/brcm,bcm54xx.yaml b/Documentation/devicetree/bindings/net/brcm,bcm54xx.yaml
new file mode 100644
index 000000000000..3ad226efe21d
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/brcm,bcm54xx.yaml
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/brcm,bcm54xx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom Ethernet PHYs
+
+maintainers:
+  - Rafał Miłecki <rafal@milecki.pl>
+
+allOf:
+  - $ref: ethernet-phy.yaml#
+
+properties:
+  compatible:
+    enum:
+      - ethernet-phy-id600d.84a6
+
+  brcm,master-mode:
+    description: PHY requires setting into master mode
+    type: boolean
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    mdio {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        ethernet-phy@0 {
+            compatible = "ethernet-phy-id600d.84a6";
+            reg = <0>;
+            brcm,master-mode;
+        };
+    };
-- 
2.51.0