* Marvell Xenon MMC controller
This file documents the properties used by the sdhci-xenon drivers.

Required properties:
- compatible: Should be "marvell,armada-3700-sdhci".
- reg: Base register offset for the SDHCI registers and pad control registers.
- status: Enable or disable this node

Optional properties:
- bus-width: Number of data lines, can be <1>, <4>, or <8>.  The default
  will be <1> if the property is absent.
- vqmmc-supply: The signal voltage supplier for SDIO if needed. For example,
  on port0 it needs a gpio regulator to supply signal voltage.
- marvell,pad-type: The property indicates the pad tye for sdio port, for example,
  the port1 is emmc and the pad type is fixed with voltage of 1.8V.

Example:
sdhci0: sdhci@d0000 {
       compatible = "marvell,armada-3700-sdhci",
       reg = <0xd0000 0x300
              0x1e808 0x4>;
       bus-width = <4>;
       vqmmc-supply = <&vcc_sd_reg0>;
       status = "disabled";
};

sdhci1: sdhci@d8000 {
       compatible = "marvell,armada-3700-sdhci",
       reg = <0xd8000 0x300
              0x17808 0x4>;
       bus-width = <8>;
       marvell,pad-type = "fixed-1-8v";
       status = "disabled";
};

The vqmmc-supply example on sdio port0:
vcc_sd_reg0: regulator@0 {
       compatible = "regulator-gpio";
       regulator-name = "vcc_sd0";
       regulator-min-microvolt = <1800000>;
       regulator-max-microvolt = <3300000>;
       regulator-type = "voltage";
       states = <1800000 0x1
                 3300000 0x0>;
       gpios = <&gpio1 23 GPIO_ACTIVE_HIGH>;
};
