dt-bindings: mfd: Add max77759 binding

The Maxim MAX77759 is a companion PMIC for USB Type-C applications and
includes Battery Charger, Fuel Gauge, temperature sensors, USB Type-C
Port Controller (TCPC), NVMEM, and a GPIO expander.

This describes the top-level device.

Signed-off-by: André Draszik <andre.draszik@linaro.org>
Reviewed-by: "Rob Herring (Arm)" <robh@kernel.org>
Link: https://lore.kernel.org/r/20250325-max77759-mfd-v6-3-c0870ca662ba@linaro.org
Signed-off-by: Lee Jones <lee@kernel.org>

Documentation/devicetree/bindings/mfd/maxim,max77759.yaml

@@ -0,0 +1,99 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/maxim,max77759.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Maxim Integrated MAX77759 PMIC for USB Type-C applications
+
+maintainers:
+  - André Draszik <andre.draszik@linaro.org>
+
+description: |
+  This is a part of device tree bindings for the MAX77759 companion Power
+  Management IC for USB Type-C applications.
+
+  The MAX77759 includes Battery Charger, Fuel Gauge, temperature sensors, USB
+  Type-C Port Controller (TCPC), NVMEM, and a GPIO expander.
+
+properties:
+  compatible:
+    const: maxim,max77759
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-controller: true
+
+  "#interrupt-cells":
+    const: 2
+
+  reg:
+    maxItems: 1
+
+  gpio:
+    $ref: /schemas/gpio/maxim,max77759-gpio.yaml
+
+  nvmem-0:
+    $ref: /schemas/nvmem/maxim,max77759-nvmem.yaml
+
+required:
+  - compatible
+  - interrupts
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        pmic@66 {
+            compatible = "maxim,max77759";
+            reg = <0x66>;
+            interrupts-extended = <&gpa8 3 IRQ_TYPE_LEVEL_LOW>;
+
+            interrupt-controller;
+            #interrupt-cells = <2>;
+
+            gpio {
+                compatible = "maxim,max77759-gpio";
+
+                gpio-controller;
+                #gpio-cells = <2>;
+
+                interrupt-controller;
+                #interrupt-cells = <2>;
+            };
+
+            nvmem-0 {
+                compatible = "maxim,max77759-nvmem";
+
+                nvmem-layout {
+                    compatible = "fixed-layout";
+                    #address-cells = <1>;
+                    #size-cells = <1>;
+
+                    reboot-mode@0 {
+                        reg = <0x0 0x4>;
+                    };
+
+                    boot-reason@4 {
+                        reg = <0x4 0x4>;
+                    };
+
+                    shutdown-user-flag@8 {
+                        reg = <0x8 0x1>;
+                    };
+
+                    rsoc@10 {
+                        reg = <0xa 0x2>;
+                    };
+                };
+            };
+        };
+    };