xref: /openbmc/linux/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.yaml (revision 9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e)
172f47aecSJisheng Zhang# SPDX-License-Identifier: GPL-2.0
272f47aecSJisheng Zhang%YAML 1.2
372f47aecSJisheng Zhang---
472f47aecSJisheng Zhang$id: http://devicetree.org/schemas/mmc/mmc-pwrseq-simple.yaml#
572f47aecSJisheng Zhang$schema: http://devicetree.org/meta-schemas/core.yaml#
672f47aecSJisheng Zhang
784e85359SKrzysztof Kozlowskititle: Simple MMC power sequence provider
872f47aecSJisheng Zhang
972f47aecSJisheng Zhangmaintainers:
1072f47aecSJisheng Zhang  - Ulf Hansson <ulf.hansson@linaro.org>
1172f47aecSJisheng Zhang
1272f47aecSJisheng Zhangdescription:
1372f47aecSJisheng Zhang  The purpose of the simple MMC power sequence provider is to supports a set
1472f47aecSJisheng Zhang  of common properties between various SOC designs. It thus enables us to use
1572f47aecSJisheng Zhang  the same provider for several SOC designs.
1672f47aecSJisheng Zhang
1772f47aecSJisheng Zhangproperties:
1872f47aecSJisheng Zhang  compatible:
1972f47aecSJisheng Zhang    const: mmc-pwrseq-simple
2072f47aecSJisheng Zhang
2172f47aecSJisheng Zhang  reset-gpios:
2272f47aecSJisheng Zhang    minItems: 1
239381118fSKrzysztof Kozlowski    # Put some limit to avoid false warnings
249381118fSKrzysztof Kozlowski    maxItems: 32
2572f47aecSJisheng Zhang    description:
2672f47aecSJisheng Zhang      contains a list of GPIO specifiers. The reset GPIOs are asserted
2772f47aecSJisheng Zhang      at initialization and prior we start the power up procedure of the card.
2872f47aecSJisheng Zhang      They will be de-asserted right after the power has been provided to the
2972f47aecSJisheng Zhang      card.
3072f47aecSJisheng Zhang
3172f47aecSJisheng Zhang  clocks:
3272f47aecSJisheng Zhang    minItems: 1
3372f47aecSJisheng Zhang    description: Handle for the entry in clock-names.
3472f47aecSJisheng Zhang
3572f47aecSJisheng Zhang  clock-names:
3672f47aecSJisheng Zhang    items:
3772f47aecSJisheng Zhang      - const: ext_clock
3872f47aecSJisheng Zhang    description: External clock provided to the card.
3972f47aecSJisheng Zhang
4072f47aecSJisheng Zhang  post-power-on-delay-ms:
4172f47aecSJisheng Zhang    description:
4272f47aecSJisheng Zhang      Delay in ms after powering the card and de-asserting the
4372f47aecSJisheng Zhang      reset-gpios (if any).
4472f47aecSJisheng Zhang
4572f47aecSJisheng Zhang  power-off-delay-us:
4672f47aecSJisheng Zhang    description:
4772f47aecSJisheng Zhang      Delay in us after asserting the reset-gpios (if any)
4872f47aecSJisheng Zhang      during power off of the card.
4972f47aecSJisheng Zhang
5072f47aecSJisheng Zhangrequired:
5172f47aecSJisheng Zhang  - compatible
5272f47aecSJisheng Zhang
535be478f9SRob HerringadditionalProperties: false
545be478f9SRob Herring
5572f47aecSJisheng Zhangexamples:
5672f47aecSJisheng Zhang  - |
5772f47aecSJisheng Zhang    #include <dt-bindings/gpio/gpio.h>
58*bb065c6fSKrzysztof Kozlowski    pwrseq {
5972f47aecSJisheng Zhang      compatible = "mmc-pwrseq-simple";
6072f47aecSJisheng Zhang      reset-gpios = <&gpio1 12 GPIO_ACTIVE_LOW>;
6172f47aecSJisheng Zhang      clocks = <&clk_32768_ck>;
6272f47aecSJisheng Zhang      clock-names = "ext_clock";
6372f47aecSJisheng Zhang    };
6472f47aecSJisheng Zhang...
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