diff --git a/Documentation/devicetree/bindings/mfd/stmfx.txt b/Documentation/devicetree/bindings/mfd/stmfx.txt
deleted file mode 100644
index f0c2f7fcf5c7..000000000000
--- a/Documentation/devicetree/bindings/mfd/stmfx.txt
+++ /dev/null
@@ -1,28 +0,0 @@
-STMicroelectonics Multi-Function eXpander (STMFX) Core bindings
-
-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.
-
-Required properties:
-- compatible: should be "st,stmfx-0300".
-- reg: I2C slave address of the device.
-- interrupts: interrupt specifier triggered by MFX_IRQ_OUT signal.
-  Please refer to ../interrupt-controller/interrupt.txt
-
-Optional properties:
-- drive-open-drain: configure MFX_IRQ_OUT as open drain.
-- vdd-supply: phandle of the regulator supplying STMFX.
-
-Example:
-
-	stmfx: stmfx@42 {
-		compatible = "st,stmfx-0300";
-		reg = <0x42>;
-		interrupts = <8 IRQ_TYPE_EDGE_RISING>;
-		interrupt-parent = <&gpioi>;
-		vdd-supply = <&v3v3>;
-	};
-
-Please refer to ../pinctrl/pinctrl-stmfx.txt for STMFX GPIO expander function bindings.
diff --git a/Documentation/devicetree/bindings/mfd/stmfx.yaml b/Documentation/devicetree/bindings/mfd/stmfx.yaml
new file mode 100644
index 000000000000..1af906fb876f
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/stmfx.yaml
@@ -0,0 +1,120 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/stmfx.yaml#
+$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
+
+    $ref: ../pinctrl/pincfg-node.yaml
+
+    properties:
+      compatible:
+        const: st,stmfx-0300-pinctrl
+
+      "#gpio-cells":
+        const: 2
+
+      "#interrupt-cells":
+        const: 2
+
+      gpio-controller: true
+
+      interrupt-controller: true
+
+      gpio-ranges:
+        description: if all STMFX pins[24:0] are available (no other STMFX function in use),
+                     you should use gpio-ranges = <&stmfx_pinctrl 0 0 24>;
+                     if agpio[3:0] are not available (STMFX Touchscreen function in use),
+                     you should use gpio-ranges = <&stmfx_pinctrl 0 0 16>, <&stmfx_pinctrl 20 20 4>;
+                     if agpio[7:4] are not available (STMFX IDD function in use),
+                     you should use gpio-ranges = <&stmfx_pinctrl 0 0 20>;
+        maxItems: 1
+
+    patternProperties:
+      "^[a-zA-Z][a-zA-Z0-9_]+$":
+        type: object
+        $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
+
+    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@0 {
+      #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 = "gpio0", "gpio1", "gpio2", "gpio3", "gpio4";
+            drive-push-pull;
+            bias-pull-up;
+          };
+        };
+      };
+    };
+...
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-stmfx.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-stmfx.txt
deleted file mode 100644
index c1b4c1819b84..000000000000
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-stmfx.txt
+++ /dev/null
@@ -1,116 +0,0 @@
-STMicroelectronics Multi-Function eXpander (STMFX) GPIO expander bindings
-
-ST Multi-Function eXpander (STMFX) offers up to 24 GPIOs expansion.
-Please refer to ../mfd/stmfx.txt for STMFX Core bindings.
-
-Required properties:
-- compatible: should be "st,stmfx-0300-pinctrl".
-- #gpio-cells: should be <2>, the first cell is the GPIO number and the second
-  cell is the gpio flags in accordance with <dt-bindings/gpio/gpio.h>.
-- gpio-controller: marks the device as a GPIO controller.
-- #interrupt-cells: should be <2>, the first cell is the GPIO number and the
-  second cell is the interrupt flags in accordance with
-  <dt-bindings/interrupt-controller/irq.h>.
-- interrupt-controller: marks the device as an interrupt controller.
-- gpio-ranges: specifies the mapping between gpio controller and pin
-  controller pins. Check "Concerning gpio-ranges property" below.
-Please refer to ../gpio/gpio.txt.
-
-Please refer to pinctrl-bindings.txt for pin configuration.
-
-Required properties for pin configuration sub-nodes:
-- pins: list of pins to which the configuration applies.
-
-Optional properties for pin configuration sub-nodes (pinconf-generic ones):
-- bias-disable: disable any bias on the pin.
-- bias-pull-up: the pin will be pulled up.
-- bias-pull-pin-default: use the pin-default pull state.
-- bias-pull-down: the pin will be pulled down.
-- drive-open-drain: the pin will be driven with open drain.
-- drive-push-pull: the pin will be driven actively high and low.
-- output-high: the pin will be configured as an output driving high level.
-- output-low: the pin will be configured as an output driving low level.
-
-Note that STMFX pins[15:0] are called "gpio[15:0]", and STMFX pins[23:16] are
-called "agpio[7:0]". Example, to refer to pin 18 of STMFX, use "agpio2".
-
-Concerning gpio-ranges property:
-- 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>;
-
-
-Example:
-
-	stmfx: stmfx@42 {
-		...
-
-		stmfx_pinctrl: stmfx-pin-controller {
-			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 = "gpio0", "gpio1", "gpio2", "gpio3", "gpio4";
-				drive-push-pull;
-				bias-pull-up;
-			};
-		};
-	};
-
-Example of STMFX GPIO consumers:
-
-	joystick {
-		compatible = "gpio-keys";
-		#address-cells = <1>;
-		#size-cells = <0>;
-		pinctrl-0 = <&joystick_pins>;
-		pinctrl-names = "default";
-		button-0 {
-			label = "JoySel";
-			linux,code = <KEY_ENTER>;
-			interrupt-parent = <&stmfx_pinctrl>;
-			interrupts = <0 IRQ_TYPE_EDGE_RISING>;
-		};
-		button-1 {
-			label = "JoyDown";
-			linux,code = <KEY_DOWN>;
-			interrupt-parent = <&stmfx_pinctrl>;
-			interrupts = <1 IRQ_TYPE_EDGE_RISING>;
-		};
-		button-2 {
-			label = "JoyLeft";
-			linux,code = <KEY_LEFT>;
-			interrupt-parent = <&stmfx_pinctrl>;
-			interrupts = <2 IRQ_TYPE_EDGE_RISING>;
-		};
-		button-3 {
-			label = "JoyRight";
-			linux,code = <KEY_RIGHT>;
-			interrupt-parent = <&stmfx_pinctrl>;
-			interrupts = <3 IRQ_TYPE_EDGE_RISING>;
-		};
-		button-4 {
-			label = "JoyUp";
-			linux,code = <KEY_UP>;
-			interrupt-parent = <&stmfx_pinctrl>;
-			interrupts = <4 IRQ_TYPE_EDGE_RISING>;
-		};
-	};
-
-	leds {
-		compatible = "gpio-leds";
-		orange {
-			gpios = <&stmfx_pinctrl 17 1>;
-		};
-
-		blue {
-			gpios = <&stmfx_pinctrl 19 1>;
-		};
-	}
