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+* Atmel High Speed MultiMedia Card Interface
+
+This controller on atmel products 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 atmel-mci driver.
+
+1) MCI node
+
+Required properties:
+- compatible: should be "atmel,hsmci"
+- #address-cells: should be one. The cell is the slot id.
+- #size-cells: should be zero.
+- at least one slot node
+- clock-names: tuple listing input clock names.
+ Required elements: "mci_clk"
+- clocks: phandles to input clocks.
+
+The node contains child nodes for each slot that the platform uses
+
+Example MCI node:
+
+mmc0: mmc@f0008000 {
+ compatible = "atmel,hsmci";
+ reg = <0xf0008000 0x600>;
+ interrupts = <12 4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ clock-names = "mci_clk";
+ clocks = <&mci0_clk>;
+
+ [ child node definitions...]
+};
+
+2) slot nodes
+
+Required properties:
+- reg: should contain the slot id.
+- bus-width: number of data lines connected to the controller
+
+Optional properties:
+- cd-gpios: specify GPIOs for card detection
+- cd-inverted: invert the value of external card detect gpio line
+- wp-gpios: specify GPIOs for write protection
+
+Example slot node:
+
+slot@0 {
+ reg = <0>;
+ bus-width = <4>;
+ cd-gpios = <&pioD 15 0>
+ cd-inverted;
+};
+
+Example full MCI node:
+mmc0: mmc@f0008000 {
+ compatible = "atmel,hsmci";
+ reg = <0xf0008000 0x600>;
+ interrupts = <12 4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ slot@0 {
+ reg = <0>;
+ bus-width = <4>;
+ cd-gpios = <&pioD 15 0>
+ cd-inverted;
+ };
+ slot@1 {
+ reg = <1>;
+ bus-width = <4>;
+ };
+};