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diff --git a/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml b/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml
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+++ b/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml
@@ -0,0 +1,133 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/st,stm32-uart.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+maintainers:
+  - Erwan Le Ray <erwan.leray@foss.st.com>
+
+title: STMicroelectronics STM32 USART bindings
+
+properties:
+  compatible:
+    enum:
+      - st,stm32-uart
+      - st,stm32f7-uart
+      - st,stm32h7-uart
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  label:
+    description: label associated with this uart
+
+  st,hw-flow-ctrl:
+    description: enable hardware flow control (deprecated)
+    $ref: /schemas/types.yaml#/definitions/flag
+
+  uart-has-rtscts: true
+
+  rx-tx-swap: true
+
+  dmas:
+    minItems: 1
+    maxItems: 2
+
+  dma-names:
+    items:
+      enum: [ rx, tx ]
+    minItems: 1
+    maxItems: 2
+
+# cts-gpios and rts-gpios properties can be used instead of 'uart-has-rtscts'
+# or 'st,hw-flow-ctrl' (deprecated) for making use of any gpio pins for flow
+# control instead of dedicated pins.
+#
+# It should be noted that both cts-gpios/rts-gpios and 'uart-has-rtscts' or
+# 'st,hw-flow-ctrl' (deprecated) properties cannot co-exist in a design.
+  cts-gpios: true
+  rts-gpios: true
+
+  wakeup-source: true
+
+  rs485-rts-delay: true
+  rs485-rts-active-low: true
+  linux,rs485-enabled-at-boot-time: true
+  rs485-rx-during-tx: true
+
+  rx-threshold:
+    description:
+      If value is set to 1, RX FIFO threshold is disabled.
+    enum: [1, 2, 4, 8, 12, 14, 16]
+    default: 8
+
+  tx-threshold:
+    description:
+      If value is set to 1, TX FIFO threshold is disabled.
+    enum: [1, 2, 4, 8, 12, 14, 16]
+    default: 8
+
+allOf:
+  - $ref: rs485.yaml#
+  - $ref: serial.yaml#
+  - if:
+      required:
+        - st,hw-flow-ctrl
+    then:
+      properties:
+        cts-gpios: false
+        rts-gpios: false
+  - if:
+      properties:
+        compatible:
+          const: st,stm32-uart
+    then:
+      properties:
+        rx-tx-swap: false
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - st,stm32-uart
+              - st,stm32f7-uart
+    then:
+      properties:
+        rx-threshold: false
+        tx-threshold: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/stm32mp1-clks.h>
+    usart1: serial@40011000 {
+      compatible = "st,stm32h7-uart";
+      reg = <0x40011000 0x400>;
+      interrupts = <37>;
+      clocks = <&rcc 0 164>;
+      dmas = <&dma2 2 4 0x414 0x0>,
+             <&dma2 7 4 0x414 0x0>;
+      dma-names = "rx", "tx";
+      rx-threshold = <4>;
+      tx-threshold = <4>;
+      rs485-rts-active-low;
+    };
+
+...