dt-bindings: arm: mediatek: document WED binding for MT7622

Document the binding for the Wireless Ethernet Dispatch core on the MT7622
SoC, which is used for Ethernet->WLAN offloading
Add related info in mediatek-net bindings.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7622-wed.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/arm/mediatek/mediatek,mt7622-wed.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: MediaTek Wireless Ethernet Dispatch Controller for MT7622
+
+maintainers:
+  - Lorenzo Bianconi <lorenzo@kernel.org>
+  - Felix Fietkau <nbd@nbd.name>
+
+description:
+  The mediatek wireless ethernet dispatch controller can be configured to
+  intercept and handle access to the WLAN DMA queues and PCIe interrupts
+  and implement hardware flow offloading from ethernet to WLAN.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - mediatek,mt7622-wed
+      - const: syscon
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+    soc {
+      #address-cells = <2>;
+      #size-cells = <2>;
+      wed0: wed@1020a000 {
+        compatible = "mediatek,mt7622-wed","syscon";
+        reg = <0 0x1020a000 0 0x1000>;
+        interrupts = <GIC_SPI 214 IRQ_TYPE_LEVEL_LOW>;
+      };
+    };

Documentation/devicetree/bindings/net/mediatek-net.txt

@@ -46,6 +46,8 @@ Optional properties:
 - mediatek,cci-control: phandle to the cache coherent interconnect node
 - mediatek,hifsys: phandle to the mediatek hifsys controller used to provide
 	various clocks and reset to the system.
+- mediatek,wed: a list of phandles to wireless ethernet dispatch nodes for
+	MT7622 SoC.
 
 * Ethernet MAC node