1 files changed, 122 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mfd/st,stmfx.yaml b/Documentation/devicetree/bindings/mfd/st,stmfx.yaml
new file mode 100644
index 000000000..888ab4b5d
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/st,stmfx.yaml
@@ -0,0 +1,122 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/st,stmfx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectonics Multi-Function eXpander (STMFX) bindings
+
+description: ST Multi-Function eXpander (STMFX) is a slave controller using I2C for
+               communication with the main MCU. Its main features are GPIO expansion,
+               main MCU IDD measurement (IDD is the amount of current that flows
+               through VDD) and resistive touchscreen controller.
+
+maintainers:
+  - Amelie Delaunay <amelie.delaunay@st.com>
+
+properties:
+  compatible:
+    const: st,stmfx-0300
+
+  reg:
+    enum: [ 0x42, 0x43 ]
+
+  interrupts:
+    maxItems: 1
+
+  drive-open-drain: true
+
+  vdd-supply:
+    maxItems: 1
+
+  pinctrl:
+    type: object
+
+    properties:
+      compatible:
+        const: st,stmfx-0300-pinctrl
+
+      "#gpio-cells":
+        const: 2
+
+      "#interrupt-cells":
+        const: 2
+
+      gpio-controller: true
+
+      interrupt-controller: true
+
+      gpio-ranges:
+        description: if all STMFX pins[24:0] are available (no other STMFX function in use),
+                     you should use gpio-ranges = <&stmfx_pinctrl 0 0 24>;
+                     if agpio[3:0] are not available (STMFX Touchscreen function in use),
+                     you should use gpio-ranges = <&stmfx_pinctrl 0 0 16>, <&stmfx_pinctrl 20 20 4>;
+                     if agpio[7:4] are not available (STMFX IDD function in use),
+                     you should use gpio-ranges = <&stmfx_pinctrl 0 0 20>;
+        maxItems: 1
+
+    patternProperties:
+      "^[a-zA-Z]*-pins$":
+        type: object
+
+        allOf:
+          - $ref: ../pinctrl/pinmux-node.yaml
+
+        properties:
+          pins: true
+          bias-disable: true
+          bias-pull-up: true
+          bias-pull-pin-default: true
+          bias-pull-down: true
+          drive-open-drain: true
+          drive-push-pull: true
+          output-high: true
+          output-low: true
+
+    additionalProperties: false
+
+    required:
+      - compatible
+      - "#gpio-cells"
+      - "#interrupt-cells"
+      - gpio-controller
+      - interrupt-controller
+      - gpio-ranges
+
+additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      stmfx@42 {
+        compatible = "st,stmfx-0300";
+        reg = <0x42>;
+        interrupts = <8 IRQ_TYPE_EDGE_RISING>;
+        interrupt-parent = <&gpioi>;
+        vdd-supply = <&v3v3>;
+
+        stmfx_pinctrl: pinctrl {
+          compatible = "st,stmfx-0300-pinctrl";
+          #gpio-cells = <2>;
+          #interrupt-cells = <2>;
+          gpio-controller;
+          interrupt-controller;
+          gpio-ranges = <&stmfx_pinctrl 0 0 24>;
+
+          joystick_pins: joystick-pins {
+            pins = "gpio0", "gpio1", "gpio2", "gpio3", "gpio4";
+            drive-push-pull;
+            bias-pull-up;
+          };
+        };
+      };
+    };
+...