dt-bindings: mfd: Add support for Airoha EN7581 GPIO System Controller

Add support for Airoha EN7581 GPIO System Controller which provide a
register map for controlling the GPIO, pinctrl and PWM of the SoC via
dedicated pinctrl and pwm child nodes.

Signed-off-by: Christian Marangi <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
Reviewed-by: Rob Herring (Arm) <[email protected]>
Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
Co-developed-by: Lorenzo Bianconi <[email protected]>
Signed-off-by: Lorenzo Bianconi <[email protected]>
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Linus Walleij <[email protected]>

Author: Ansuel

Documentation/devicetree/bindings/mfd/airoha,en7581-gpio-sysctl.yaml

@@ -0,0 +1,90 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/airoha,en7581-gpio-sysctl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Airoha EN7581 GPIO System Controller
+
+maintainers:
+  - Christian Marangi <[email protected]>
+  - Lorenzo Bianconi <[email protected]>
+
+description:
+  Airoha EN7581 SoC GPIO system controller which provided a register map
+  for controlling the GPIO, pins and PWM of the SoC.
+
+properties:
+  compatible:
+    items:
+      - const: airoha,en7581-gpio-sysctl
+      - const: syscon
+      - const: simple-mfd
+
+  reg:
+    maxItems: 1
+
+  pinctrl:
+    type: object
+    $ref: /schemas/pinctrl/airoha,en7581-pinctrl.yaml
+    description:
+      Child node definition for EN7581 Pin controller
+
+  pwm:
+    type: object
+    $ref: /schemas/pwm/airoha,en7581-pwm.yaml
+    description:
+      Child node definition for EN7581 PWM controller
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    system-controller@1fbf0200 {
+      compatible = "airoha,en7581-gpio-sysctl", "syscon", "simple-mfd";
+      reg = <0x1fbf0200 0xc0>;
+
+      pinctrl {
+        compatible = "airoha,en7581-pinctrl";
+
+        interrupt-parent = <&gic>;
+        interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>;
+
+        gpio-controller;
+        #gpio-cells = <2>;
+
+        interrupt-controller;
+        #interrupt-cells = <2>;
+
+        mmc-pins {
+          mux {
+            function = "emmc";
+            groups = "emmc";
+          };
+        };
+
+        mdio-pins {
+          mux {
+            function = "mdio";
+            groups = "mdio";
+          };
+
+          conf {
+            pins = "gpio2";
+            output-enable;
+          };
+        };
+      };
+
+      pwm {
+        compatible = "airoha,en7581-pwm";
+
+        #pwm-cells = <3>;
+      };
+    };