dt-bindings: mmc: Convert imx esdhc to json-schema

* Freescale Enhanced Secure Digital Host Controller (eSDHC) for i.MX

The Enhanced Secure Digital Host Controller on Freescale i.MX family

provides an interface for MMC, SD, and SDIO types of memory cards.

This file documents differences between the core properties described

by mmc.txt and the properties used by the sdhci-esdhc-imx driver.

Required properties:

- compatible : Should be "fsl,<chip>-esdhc", the supported chips include

	       "fsl,imx25-esdhc"

	       "fsl,imx35-esdhc"

	       "fsl,imx51-esdhc"

	       "fsl,imx53-esdhc"

	       "fsl,imx6q-usdhc"

	       "fsl,imx6sl-usdhc"

	       "fsl,imx6sx-usdhc"

	       "fsl,imx6ull-usdhc"

	       "fsl,imx7d-usdhc"

	       "fsl,imx7ulp-usdhc"

	       "fsl,imx8mq-usdhc"

	       "fsl,imx8mm-usdhc"

	       "fsl,imx8mn-usdhc"

	       "fsl,imx8mp-usdhc"

	       "fsl,imx8qm-usdhc"

	       "fsl,imx8qxp-usdhc"

Optional properties:

- fsl,wp-controller : Indicate to use controller internal write protection

- fsl,delay-line : Specify the number of delay cells for override mode.

  This is used to set the clock delay for DLL(Delay Line) on override mode

  to select a proper data sampling window in case the clock quality is not good

  due to signal path is too long on the board. Please refer to eSDHC/uSDHC

  chapter, DLL (Delay Line) section in RM for details.

- voltage-ranges : Specify the voltage range in case there are software

  transparent level shifters on the outputs of the controller. Two cells are

  required, first cell specifies minimum slot voltage (mV), second cell

  specifies maximum slot voltage (mV). Several ranges could be specified.

- fsl,tuning-start-tap: Specify the start dealy cell point when send first CMD19

  in tuning procedure.

- fsl,tuning-step: Specify the increasing delay cell steps in tuning procedure.

  The uSDHC use one delay cell as default increasing step to do tuning process.

  This property allows user to change the tuning step to more than one delay

  cells which is useful for some special boards or cards when the default

  tuning step can't find the proper delay window within limited tuning retries.

- fsl,strobe-dll-delay-target: Specify the strobe dll control slave delay target.

  This delay target programming host controller loopback read clock, and this

  property allows user to change the delay target for the strobe input read clock.

  If not use this property, driver default set the delay target to value 7.

  Only eMMC HS400 mode need to take care of this property.

Examples:

esdhc@70004000 {

	compatible = "fsl,imx51-esdhc";

	reg = <0x70004000 0x4000>;

	interrupts = <1>;

	fsl,wp-controller;

};

esdhc@70008000 {

	compatible = "fsl,imx51-esdhc";

	reg = <0x70008000 0x4000>;

	interrupts = <2>;

	cd-gpios = <&gpio1 6 0>; /* GPIO1_6 */

	wp-gpios = <&gpio1 5 0>; /* GPIO1_5 */

};

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

%YAML 1.2

---

$id: http://devicetree.org/schemas/mmc/fsl-imx-esdhc.yaml#

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

title: Freescale Enhanced Secure Digital Host Controller (eSDHC) for i.MX

maintainers:

  - Shawn Guo <shawn.guo@linaro.org>

allOf:

  - $ref: "mmc-controller.yaml"

description: |

  The Enhanced Secure Digital Host Controller on Freescale i.MX family

  provides an interface for MMC, SD, and SDIO types of memory cards.

  This file documents differences between the core properties described

  by mmc.txt and the properties used by the sdhci-esdhc-imx driver.

properties:

  compatible:

    enum:

      - fsl,imx25-esdhc

      - fsl,imx35-esdhc

      - fsl,imx51-esdhc

      - fsl,imx53-esdhc

      - fsl,imx6q-usdhc

      - fsl,imx6sl-usdhc

      - fsl,imx6sx-usdhc

      - fsl,imx6ull-usdhc

      - fsl,imx7d-usdhc

      - fsl,imx7ulp-usdhc

      - fsl,imx8mq-usdhc

      - fsl,imx8mm-usdhc

      - fsl,imx8mn-usdhc

      - fsl,imx8mp-usdhc

      - fsl,imx8qm-usdhc

      - fsl,imx8qxp-usdhc

  reg:

    maxItems: 1

  interrupts:

    maxItems: 1

  fsl,wp-controller:

    description: |

      boolean, if present, indicate to use controller internal write protection.

    type: boolean

  fsl,delay-line:

    $ref: /schemas/types.yaml#/definitions/uint32

    description: |

      Specify the number of delay cells for override mode.

      This is used to set the clock delay for DLL(Delay Line) on override mode

      to select a proper data sampling window in case the clock quality is not good

      due to signal path is too long on the board. Please refer to eSDHC/uSDHC

      chapter, DLL (Delay Line) section in RM for details.

    default: 0

  voltage-ranges:

    $ref: '/schemas/types.yaml#/definitions/uint32-matrix'

    description: |

      Specify the voltage range in case there are software transparent level

      shifters on the outputs of the controller. Two cells are required, first

      cell specifies minimum slot voltage (mV), second cell specifies maximum

      slot voltage (mV).

    items:

      items:

        - description: value for minimum slot voltage

        - description: value for maximum slot voltage

    maxItems: 1

  fsl,tuning-start-tap:

    $ref: /schemas/types.yaml#/definitions/uint32

    description: |

      Specify the start delay cell point when send first CMD19 in tuning procedure.

    default: 0

  fsl,tuning-step:

    $ref: /schemas/types.yaml#/definitions/uint32

    description: |

      Specify the increasing delay cell steps in tuning procedure.

      The uSDHC use one delay cell as default increasing step to do tuning process.

      This property allows user to change the tuning step to more than one delay

      cells which is useful for some special boards or cards when the default

      tuning step can't find the proper delay window within limited tuning retries.

    default: 0

  fsl,strobe-dll-delay-target:

    $ref: /schemas/types.yaml#/definitions/uint32

    description: |

      Specify the strobe dll control slave delay target.

      This delay target programming host controller loopback read clock, and this

      property allows user to change the delay target for the strobe input read clock.

      If not use this property, driver default set the delay target to value 7.

      Only eMMC HS400 mode need to take care of this property.

    default: 0

required:

  - compatible

  - reg

  - interrupts

unevaluatedProperties: false

examples:

  - |

    mmc@70004000 {

        compatible = "fsl,imx51-esdhc";

        reg = <0x70004000 0x4000>;

        interrupts = <1>;

        fsl,wp-controller;

    };

    mmc@70008000 {

        compatible = "fsl,imx51-esdhc";

        reg = <0x70008000 0x4000>;

        interrupts = <2>;

        cd-gpios = <&gpio1 6 0>; /* GPIO1_6 */

        wp-gpios = <&gpio1 5 0>; /* GPIO1_5 */

    };