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diff --git a/Documentation/devicetree/bindings/i2c/opencores,i2c-ocores.yaml b/Documentation/devicetree/bindings/i2c/opencores,i2c-ocores.yaml
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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/opencores,i2c-ocores.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: OpenCores I2C controller
+
+maintainers:
+  - Peter Korsgaard <peter@korsgaard.com>
+  - Andrew Lunn <andrew@lunn.ch>
+
+allOf:
+  - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - sifive,fu740-c000-i2c # Opencore based IP block FU740-C000 SoC
+              - sifive,fu540-c000-i2c # Opencore based IP block FU540-C000 SoC
+          - const: sifive,i2c0
+      - enum:
+          - opencores,i2c-ocores
+          - aeroflexgaisler,i2cmst
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-frequency:
+    description: |
+      clock-frequency property is meant to control the bus frequency for i2c bus
+      drivers, but it was incorrectly used to specify i2c controller input clock
+      frequency. So the following rules are set to fix this situation:
+      - if clock-frequency is present and neither opencores,ip-clock-frequency nor
+        clocks are, then clock-frequency specifies i2c controller clock frequency.
+        This is to keep backwards compatibility with setups using old DTB. i2c bus
+        frequency is fixed at 100 KHz.
+      - if clocks is present it specifies i2c controller clock. clock-frequency
+        property specifies i2c bus frequency.
+      - if opencores,ip-clock-frequency is present it specifies i2c controller
+        clock frequency. clock-frequency property specifies i2c bus frequency.
+    default: 100000
+
+  reg-io-width:
+    description: |
+      io register width in bytes
+    enum: [1, 2, 4]
+
+  reg-shift:
+    description: |
+      device register offsets are shifted by this value
+    default: 0
+
+  regstep:
+    description: |
+      deprecated, use reg-shift above
+    deprecated: true
+
+  opencores,ip-clock-frequency:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: |
+      Frequency of the controller clock in Hz. Mutually exclusive with clocks.
+      See the note above.
+
+required:
+  - compatible
+  - reg
+  - "#address-cells"
+  - "#size-cells"
+
+oneOf:
+  - required:
+      - opencores,ip-clock-frequency
+  - required:
+      - clocks
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    i2c@a0000000 {
+      compatible = "opencores,i2c-ocores";
+      reg = <0xa0000000 0x8>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+      interrupts = <10>;
+      opencores,ip-clock-frequency = <20000000>;
+
+      reg-shift = <0>;	/* 8 bit registers */
+      reg-io-width = <1>;	/* 8 bit read/write */
+    };
+
+    i2c@b0000000 {
+      compatible = "opencores,i2c-ocores";
+      reg = <0xa0000000 0x8>;
+      #address-cells = <1>;
+      #size-cells = <0>;
+      interrupts = <10>;
+      clocks = <&osc>;
+      clock-frequency = <400000>; /* i2c bus frequency 400 KHz */
+
+      reg-shift = <0>;	/* 8 bit registers */
+      reg-io-width = <1>;	/* 8 bit read/write */
+    };
+...