# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/mmc/mmc-pwrseq-emmc.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Simple eMMC hardware reset provider

maintainers:
  - Ulf Hansson <ulf.hansson@linaro.org>

description:
  The purpose of this driver is to perform standard eMMC hw reset
  procedure, as described by Jedec 4.4 specification. This procedure is
  performed just after MMC core enabled power to the given mmc host (to
  fix possible issues if bootloader has left eMMC card in initialized or
  unknown state), and before performing complete system reboot (also in
  case of emergency reboot call). The latter is needed on boards, which
  doesn't have hardware reset logic connected to emmc card and (limited or
  broken) ROM bootloaders are unable to read second stage from the emmc
  card if the card is left in unknown or already initialized state.

properties:
  compatible:
    const: mmc-pwrseq-emmc

  reset-gpios:
    minItems: 1
    description:
      contains a GPIO specifier. The reset GPIO is asserted
      and then deasserted to perform eMMC card reset. To perform
      reset procedure as described in Jedec 4.4 specification, the
      gpio line should be defined as GPIO_ACTIVE_LOW.

required:
  - compatible
  - reset-gpios

additionalProperties: false

examples:
  - |
    #include <dt-bindings/gpio/gpio.h>
    pwrseq {
      compatible = "mmc-pwrseq-emmc";
      reset-gpios = <&gpio1 12 GPIO_ACTIVE_LOW>;
    };
...
