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Document the clock properties required by the atmel-mci driver. Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
74 lines
1.6 KiB
Plaintext
74 lines
1.6 KiB
Plaintext
* Atmel High Speed MultiMedia Card Interface
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This controller on atmel products provides an interface for MMC, SD and SDIO
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types of memory cards.
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This file documents differences between the core properties described
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by mmc.txt and the properties used by the atmel-mci driver.
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1) MCI node
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Required properties:
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- compatible: should be "atmel,hsmci"
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- #address-cells: should be one. The cell is the slot id.
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- #size-cells: should be zero.
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- at least one slot node
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- clock-names: tuple listing input clock names.
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Required elements: "mci_clk"
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- clocks: phandles to input clocks.
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The node contains child nodes for each slot that the platform uses
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Example MCI node:
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mmc0: mmc@f0008000 {
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compatible = "atmel,hsmci";
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reg = <0xf0008000 0x600>;
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interrupts = <12 4>;
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#address-cells = <1>;
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#size-cells = <0>;
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clock-names = "mci_clk";
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clocks = <&mci0_clk>;
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[ child node definitions...]
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};
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2) slot nodes
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Required properties:
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- reg: should contain the slot id.
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- bus-width: number of data lines connected to the controller
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Optional properties:
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- cd-gpios: specify GPIOs for card detection
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- cd-inverted: invert the value of external card detect gpio line
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- wp-gpios: specify GPIOs for write protection
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Example slot node:
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slot@0 {
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reg = <0>;
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bus-width = <4>;
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cd-gpios = <&pioD 15 0>
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cd-inverted;
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};
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Example full MCI node:
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mmc0: mmc@f0008000 {
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compatible = "atmel,hsmci";
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reg = <0xf0008000 0x600>;
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interrupts = <12 4>;
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#address-cells = <1>;
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#size-cells = <0>;
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slot@0 {
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reg = <0>;
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bus-width = <4>;
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cd-gpios = <&pioD 15 0>
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cd-inverted;
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};
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slot@1 {
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reg = <1>;
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bus-width = <4>;
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};
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};
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