dt-bindings: i2c: convert i2c-at91 to json-schema

Convert I2C binding for Atmel/Microchip SoCs to Device Tree Schema
format.
Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220310114553.184763-3-sergiu.moga@microchip.com

Documentation/devicetree/bindings/i2c/atmel,at91sam-i2c.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2022 Microchip Technology, Inc. and its subsidiaries
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/atmel,at91sam-i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: I2C for Atmel/Microchip platforms
+
+maintainers:
+  - Alexandre Belloni <alexandre.belloni@bootlin.com>
+
+properties:
+  compatible:
+    enum:
+      - atmel,at91rm9200-i2c
+      - atmel,at91sam9261-i2c
+      - atmel,at91sam9260-i2c
+      - atmel,at91sam9g20-i2c
+      - atmel,at91sam9g10-i2c
+      - atmel,at91sam9x5-i2c
+      - atmel,sama5d4-i2c
+      - atmel,sama5d2-i2c
+      - microchip,sam9x60-i2c
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+  clocks:
+    maxItems: 1
+
+  clock-frequency:
+    default: 100000
+
+  dmas:
+    items:
+      - description: TX DMA Channel Specifier
+      - description: RX DMA Channel Specifier
+
+  dma-names:
+    items:
+      - const: tx
+      - const: rx
+
+  atmel,fifo-size:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: |
+      Maximum number of data the RX and TX FIFOs can store for
+      FIFO capable I2C controllers.
+
+  scl-gpios: true
+
+  sda-gpios: true
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - "#address-cells"
+  - "#size-cells"
+  - clocks
+
+allOf:
+  - $ref: "i2c-controller.yaml"
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - atmel,sama5d4-i2c
+              - atmel,sama5d2-i2c
+              - microchip,sam9x60-i2c
+    then:
+      properties:
+        i2c-sda-hold-time-ns:
+          description:
+            TWD hold time
+          maxItems: 1
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/dma/at91.h>
+    #include <dt-bindings/gpio/gpio.h>
+
+    i2c0: i2c@fff84000 {
+        compatible = "atmel,at91sam9g20-i2c";
+        reg = <0xfff84000 0x100>;
+        interrupts = <12 IRQ_TYPE_LEVEL_HIGH 6>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+        clocks = <&twi0_clk>;
+        clock-frequency = <400000>;
+
+        eeprom@50 {
+            compatible = "atmel,24c512";
+            reg = <0x50>;
+            pagesize = <128>;
+        };
+    };
+
+    i2c1: i2c@f8034600 {
+        compatible = "atmel,sama5d2-i2c";
+        reg = <0xf8034600 0x100>;
+        interrupts = <19 IRQ_TYPE_LEVEL_HIGH 7>;
+        dmas = <&dma0
+            (AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1))
+            AT91_XDMAC_DT_PERID(11)>,
+               <&dma0
+            (AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1))
+            AT91_XDMAC_DT_PERID(12)>;
+        dma-names = "tx", "rx";
+        #address-cells = <1>;
+        #size-cells = <0>;
+        clocks = <&flx0>;
+        atmel,fifo-size = <16>;
+        i2c-sda-hold-time-ns = <336>;
+        pinctrl-names = "default", "gpio";
+        pinctrl-0 = <&pinctrl_i2c0>;
+        pinctrl-1 = <&pinctrl_i2c0_gpio>;
+        sda-gpios = <&pioA 30 GPIO_ACTIVE_HIGH>;
+        scl-gpios = <&pioA 31 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+
+        eeprom@54 {
+            compatible = "atmel,24c02";
+            reg = <0x54>;
+            pagesize = <16>;
+        };
+    };

Documentation/devicetree/bindings/i2c/i2c-at91.txt

-I2C for Atmel platforms
-
-Required properties :
-- compatible : Must be one of:
-	"atmel,at91rm9200-i2c",
-	"atmel,at91sam9261-i2c",
-	"atmel,at91sam9260-i2c",
-	"atmel,at91sam9g20-i2c",
-	"atmel,at91sam9g10-i2c",
-	"atmel,at91sam9x5-i2c",
-	"atmel,sama5d4-i2c",
-	"atmel,sama5d2-i2c",
-	"microchip,sam9x60-i2c".
-- reg: physical base address of the controller and length of memory mapped
-     region.
-- interrupts: interrupt number to the cpu.
-- #address-cells = <1>;
-- #size-cells = <0>;
-- clocks: phandles to input clocks.
-
-Optional properties:
-- clock-frequency: Desired I2C bus frequency in Hz, otherwise defaults to 100000
-- dmas: A list of two dma specifiers, one for each entry in dma-names.
-- dma-names: should contain "tx" and "rx".
-- atmel,fifo-size: maximum number of data the RX and TX FIFOs can store for FIFO
-  capable I2C controllers.
-- i2c-sda-hold-time-ns: TWD hold time, only available for:
-	"atmel,sama5d4-i2c",
-	"atmel,sama5d2-i2c",
-	"microchip,sam9x60-i2c".
-- scl-gpios: specify the gpio related to SCL pin
-- sda-gpios: specify the gpio related to SDA pin
-- pinctrl: add extra pinctrl to configure i2c pins to gpio function for i2c
-  bus recovery, call it "gpio" state
-- Child nodes conforming to i2c bus binding
-
-
-Examples :
-
-i2c0: i2c@fff84000 {
-	compatible = "atmel,at91sam9g20-i2c";
-	reg = <0xfff84000 0x100>;
-	interrupts = <12 4 6>;
-	#address-cells = <1>;
-	#size-cells = <0>;
-	clocks = <&twi0_clk>;
-	clock-frequency = <400000>;
-
-	24c512@50 {
-		compatible = "atmel,24c512";
-		reg = <0x50>;
-		pagesize = <128>;
-	}
-}
-
-i2c0: i2c@f8034600 {
-	compatible = "atmel,sama5d2-i2c";
-	reg = <0xf8034600 0x100>;
-	interrupts = <19 IRQ_TYPE_LEVEL_HIGH 7>;
-	dmas = <&dma0
-		(AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1))
-		AT91_XDMAC_DT_PERID(11)>,
-	       <&dma0
-		(AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1))
-		AT91_XDMAC_DT_PERID(12)>;
-	dma-names = "tx", "rx";
-	#address-cells = <1>;
-	#size-cells = <0>;
-	clocks = <&flx0>;
-	atmel,fifo-size = <16>;
-	i2c-sda-hold-time-ns = <336>;
-	pinctrl-names = "default", "gpio";
-	pinctrl-0 = <&pinctrl_i2c0>;
-	pinctrl-1 = <&pinctrl_i2c0_gpio>;
-	sda-gpios = <&pioA 30 GPIO_ACTIVE_HIGH>;
-	scl-gpios = <&pioA 31 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
-
-	wm8731: wm8731@1a {
-		compatible = "wm8731";
-		reg = <0x1a>;
-	};
-};