dt-bindings: net: wireless: rt2800: add SOC Wifi

Add device-tree bindings for the RT2800 SOC wifi device found in older
Ralink/Mediatek devices.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20250722212856.11343-8-rosenp@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Documentation/devicetree/bindings/net/wireless/ralink,rt2880.yaml

@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/wireless/ralink,rt2880.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Ralink RT2880 wireless device
+
+maintainers:
+  - Stanislaw Gruszka <stf_xl@wp.pl>
+
+description: |
+  This node provides properties for configuring RT2880 SOC wifi devices.
+  The node is expected to be specified as a root node of the device.
+
+allOf:
+  - $ref: ieee80211.yaml#
+
+properties:
+  compatible:
+    enum:
+      - ralink,rt2880-wifi
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    wifi@110180000 {
+      compatible = "ralink,rt2880-wifi";
+      reg = <0x10180000 0x40000>;
+      clocks = <&sysc 16>;
+      interrupt-parent = <&cpuintc>;
+      interrupts = <6>;
+    };