dt-bindings: net: Add ADIN1140

The ADIN1140 is a single port 10BASE-T1S Ethernet controller that
includes both the MAC and a PHY in the same package.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Ciprian Regus <ciprian.regus@analog.com>
Link: https://patch.msgid.link/20260708-adin1140-driver-v5-1-4aca7b51a58b@analog.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Documentation/devicetree/bindings/net/adi,ad3306.yaml

@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/adi,ad3306.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ADI ADIN1140 10BASE-T1S MAC-PHY
+
+maintainers:
+  - Ciprian Regus <ciprian.regus@analog.com>
+
+description: |
+  The ADIN1140 (also called AD3306) is a low power single port
+  10BASE-T1S MAC-PHY. It integrates an Ethernet PHY with a MAC
+  and all the associated analog circuitry.
+  The device tries to implement the Open Alliance TC6 10BASE-T1x MAC-PHY
+  Serial Interface specification and is compliant with the
+  IEEE 802.3cg-2019 Ethernet standard for 10 Mbps single pair
+  Ethernet (SPE). The device has a 4-wire SPI interface for
+  communication between the MAC and host processor.
+
+allOf:
+  - $ref: /schemas/net/ethernet-controller.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - const: adi,adin1140
+          - const: adi,ad3306
+      - const: adi,ad3306
+
+  reg:
+    maxItems: 1
+
+  spi-max-frequency:
+    maximum: 25000000
+
+  interrupts:
+    maxItems: 1
+    description: Interrupt from the MAC-PHY for receive data available
+      and error conditions
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - spi-max-frequency
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        ethernet@0 {
+            compatible = "adi,ad3306";
+            reg = <0>;
+            spi-max-frequency = <23000000>;
+
+            interrupt-parent = <&gpio>;
+            interrupts = <6 IRQ_TYPE_LEVEL_LOW>;
+
+            local-mac-address = [ 00 11 22 33 44 55 ];
+        };
+    };