dt-bindings: serial: Convert MXS auart to json-schema

* Freescale MXS Application UART (AUART)

Required properties for all SoCs:

- compatible : Should be one of fallowing variants:

	"fsl,imx23-auart" - Freescale i.MX23

	"fsl,imx28-auart" - Freescale i.MX28

	"alphascale,asm9260-auart" - Alphascale ASM9260

- reg : Address and length of the register set for the device

- interrupts : Should contain the auart interrupt numbers

- dmas: DMA specifier, consisting of a phandle to DMA controller node

  and AUART DMA channel ID.

  Refer to dma.txt and fsl-mxs-dma.txt for details.

- dma-names: "rx" for RX channel, "tx" for TX channel.

Required properties for "alphascale,asm9260-auart":

- clocks : the clocks feeding the watchdog timer. See clock-bindings.txt

- clock-names : should be set to

	"mod" - source for tick counter.

	"ahb" - ahb gate.

Optional properties:

- uart-has-rtscts : Indicate the UART has RTS and CTS lines

  for hardware flow control,

	it also means you enable the DMA support for this UART.

- {rts,cts,dtr,dsr,rng,dcd}-gpios: specify a GPIO for RTS/CTS/DTR/DSR/RI/DCD

  line respectively. It will use specified PIO instead of the peripheral

  function pin for the USART feature.

  If unsure, don't specify this property.

Example:

auart0: serial@8006a000 {

	compatible = "fsl,imx28-auart", "fsl,imx23-auart";

	reg = <0x8006a000 0x2000>;

	interrupts = <112>;

	dmas = <&dma_apbx 8>, <&dma_apbx 9>;

	dma-names = "rx", "tx";

	cts-gpios = <&gpio1 15 GPIO_ACTIVE_LOW>;

	dsr-gpios = <&gpio1 16 GPIO_ACTIVE_LOW>;

	dcd-gpios = <&gpio1 17 GPIO_ACTIVE_LOW>;

};

Note: Each auart port should have an alias correctly numbered in "aliases"

node.

Example:

aliases {

	serial0 = &auart0;

	serial1 = &auart1;

	serial2 = &auart2;

	serial3 = &auart3;

	serial4 = &auart4;

};

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

%YAML 1.2

---

$id: http://devicetree.org/schemas/serial/fsl-mxs-auart.yaml#

$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Freescale MXS Application UART (AUART)

maintainers:

  - Fabio Estevam <fabio.estevam@nxp.com>

allOf:

  - $ref: "serial.yaml"

properties:

  compatible:

    enum:

      - fsl,imx23-auart

      - fsl,imx28-auart

      - alphascale,asm9260-auart

  reg:

    maxItems: 1

  interrupts:

    maxItems: 1

  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

  clocks:

    items:

      - description: mod clock

      - description: ahb clock

    minItems: 1

  clock-names:

    items:

      - const: mod

      - const: ahb

    minItems: 1

  uart-has-rtscts: true

  rts-gpios: true

  cts-gpios: true

  dtr-gpios: true

  dsr-gpios: true

  rng-gpios: true

  dcd-gpios: true

if:

  properties:

    compatible:

      contains:

        enum:

          - alphascale,asm9260-auart

then:

  required:

    - clocks

    - clock-names

required:

  - compatible

  - reg

  - interrupts

  - dmas

  - dma-names

unevaluatedProperties: false

examples:

  - |

    aliases {

        serial0 = &auart0;

    };

    auart0: serial@8006a000 {

        compatible = "fsl,imx28-auart";

        reg = <0x8006a000 0x2000>;

        interrupts = <112>;

        dmas = <&dma_apbx 8>, <&dma_apbx 9>;

        dma-names = "rx", "tx";

        clocks = <&clks 45>;

    };