dt-bindings: i2c: Convert i2c-jz4780.txt to YAML

Convert the i2c-jz4780.txt file to ingenic,i2c.yaml.

Two things were changed in the process:
- the clock-frequency property can now only be set to the two values
  that can be set by the hardware;
- the dmas and dma-names properties are now required.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
[robh: add ref to i2c-controller.yaml]
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml

@@ -0,0 +1,88 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/ingenic,i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Ingenic SoCs I2C controller devicetree bindings
+
+maintainers:
+  - Paul Cercueil <paul@crapouillou.net>
+
+allOf:
+  - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+  $nodename:
+    pattern: "^i2c@[0-9a-f]+$"
+
+  compatible:
+    enum:
+      - ingenic,jz4780-i2c
+      - ingenic,x1000-i2c
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-frequency:
+    enum: [ 100000, 400000 ]
+
+  dmas:
+    items:
+      - description: DMA controller phandle and request line for RX
+      - description: DMA controller phandle and request line for TX
+
+  dma-names:
+    items:
+      - const: rx
+      - const: tx
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-frequency
+  - dmas
+  - dma-names
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/jz4780-cgu.h>
+    #include <dt-bindings/dma/jz4780-dma.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+    i2c@10054000 {
+      compatible = "ingenic,jz4780-i2c";
+      #address-cells = <1>;
+      #size-cells = <0>;
+      reg = <0x10054000 0x1000>;
+
+      interrupt-parent = <&intc>;
+      interrupts = <56>;
+
+      clocks = <&cgu JZ4780_CLK_SMB4>;
+      pinctrl-names = "default";
+      pinctrl-0 = <&pins_i2c4_data>;
+
+      dmas = <&dma JZ4780_DMA_SMB4_RX 0xffffffff>,
+             <&dma JZ4780_DMA_SMB4_TX 0xffffffff>;
+      dma-names = "rx", "tx";
+
+      clock-frequency = <400000>;
+
+      rtc@51 {
+        compatible = "nxp,pcf8563";
+        reg = <0x51>;
+
+        interrupt-parent = <&gpf>;
+        interrupts = <30 IRQ_TYPE_LEVEL_LOW>;
+      };
+    };