[PATCH 1/3] dt-bindings: leds: add Realtek RTL9301 port LEDs

[Ross Cawston <ross@r-sc.ca>]

Add a binding for RTL9300 switch port LEDs under software control. The
node is a child of the switch and gives the offset of the software LED
control registers; each LED child names its switch port and its place
among the port's LEDs.

Signed-off-by: Ross Cawston <ross@r-sc.ca>
---
 .../leds/realtek,rtl9301-port-leds.yaml       | 84 +++++++++++++++++++
 1 file changed, 84 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/realtek,rtl9301-port-leds.yaml

diff --git a/Documentation/devicetree/bindings/leds/realtek,rtl9301-port-leds.yaml b/Documentation/devicetree/bindings/leds/realtek,rtl9301-port-leds.yaml
new file mode 100644
index 00000000000..8d6b3552526
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/realtek,rtl9301-port-leds.yaml
@@ -0,0 +1,84 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/realtek,rtl9301-port-leds.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Realtek RTL9300 switch port LEDs under software control
+
+maintainers:
+  - Ross Cawston <ross@r-sc.ca>
+
+description: |
+  The RTL9300 switch drives up to four LEDs per port over its LED interface,
+  serial or scanned, each normally showing a hardware function chosen by the
+  LED set of the port. The LEDs listed here are taken over by software instead
+  and switched on and off as LED class devices, for port LEDs that have no
+  hardware function such as the PoE status LED of a PoE switch. The node is a
+  child of the switch, whose registers it uses.
+
+properties:
+  compatible:
+    const: realtek,rtl9301-port-leds
+
+  reg:
+    description: The software LED control registers, from SW_LED_LOAD to the
+      end of LED_PORT_SW_CTRL, as an offset into the switch registers.
+    maxItems: 1
+
+  "#address-cells":
+    const: 2
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^led@[0-9a-f]+,[0-3]$":
+    $ref: /schemas/leds/common.yaml#
+    unevaluatedProperties: false
+
+    properties:
+      reg:
+        items:
+          - items:
+              - description: Switch port
+                maximum: 27
+              - description: LED of the port, numbered as in the port's
+                  LED set
+                maximum: 3
+
+    required:
+      - reg
+
+required:
+  - compatible
+  - reg
+  - "#address-cells"
+  - "#size-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/leds/common.h>
+
+    led-controller@cc48 {
+        compatible = "realtek,rtl9301-port-leds";
+        reg = <0xcc48 0x84>;
+        #address-cells = <2>;
+        #size-cells = <0>;
+
+        led@0,2 {
+            reg = <0 2>;
+            color = <LED_COLOR_ID_GREEN>;
+            function = "poe";
+            function-enumerator = <1>;
+        };
+
+        led@8,2 {
+            reg = <8 2>;
+            color = <LED_COLOR_ID_GREEN>;
+            function = "poe";
+            function-enumerator = <2>;
+        };
+    };
-- 
2.55.0.windows.5