dt-bindings: microchip,eic: Add bindings for the Microchip EIC

Add DT bindings for Microchip External Interrupt Controller.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210927063657.2157676-2-claudiu.beznea@microchip.com

Documentation/devicetree/bindings/interrupt-controller/microchip,eic.yaml

@@ -0,0 +1,73 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/microchip,eic.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip External Interrupt Controller
+
+maintainers:
+  - Claudiu Beznea <claudiu.beznea@microchip.com>
+
+description:
+  This interrupt controller is found in Microchip SoCs (SAMA7G5) and provides
+  support for handling up to 2 external interrupt lines.
+
+properties:
+  compatible:
+    enum:
+      - microchip,sama7g5-eic
+
+  reg:
+    maxItems: 1
+
+  interrupt-controller: true
+
+  '#interrupt-cells':
+    const: 2
+    description:
+      The first cell is the input IRQ number (between 0 and 1), the second cell
+      is the trigger type as defined in interrupt.txt present in this directory.
+
+  interrupts:
+    description: |
+      Contains the GIC SPI IRQs mapped to the external interrupt lines. They
+      should be specified sequentially from output 0 to output 1.
+    minItems: 2
+    maxItems: 2
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: pclk
+
+required:
+  - compatible
+  - reg
+  - interrupt-controller
+  - '#interrupt-cells'
+  - interrupts
+  - clocks
+  - clock-names
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/at91.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    eic: interrupt-controller@e1628000 {
+      compatible = "microchip,sama7g5-eic";
+      reg = <0xe1628000 0x100>;
+      interrupt-parent = <&gic>;
+      interrupt-controller;
+      #interrupt-cells = <2>;
+      interrupts = <GIC_SPI 153 IRQ_TYPE_LEVEL_HIGH>,
+                   <GIC_SPI 154 IRQ_TYPE_LEVEL_HIGH>;
+      clocks = <&pmc PMC_TYPE_PERIPHERAL 37>;
+      clock-names = "pclk";
+    };
+
+...