mtd: nand: add sunxi NFC dt bindings doc

Add the sunxi NAND Flash Controller dt bindings documentation.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

diff --git a/Documentation/devicetree/bindings/mtd/sunxi-nand.txt b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt
new file mode 100644 (file)
index 0000000..0273adb
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+++ b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt
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+Allwinner NAND Flash Controller (NFC)
+
+Required properties:
+- compatible : "allwinner,sun4i-a10-nand".
+- reg : shall contain registers location and length for data and reg.
+- interrupts : shall define the nand controller interrupt.
+- #address-cells: shall be set to 1. Encode the nand CS.
+- #size-cells : shall be set to 0.
+- clocks : shall reference nand controller clocks.
+- clock-names : nand controller internal clock names. Shall contain :
+    * "ahb" : AHB gating clock
+    * "mod" : nand controller clock
+
+Optional children nodes:
+Children nodes represent the available nand chips.
+
+Optional properties:
+- allwinner,rb : shall contain the native Ready/Busy ids.
+ or
+- rb-gpios : shall contain the gpios used as R/B pins.
+- nand-ecc-mode : one of the supported ECC modes ("hw", "hw_syndrome", "soft",
+  "soft_bch" or "none")
+
+see Documentation/devicetree/mtd/nand.txt for generic bindings.
+
+
+Examples:
+nfc: nand@01c03000 {
+       compatible = "allwinner,sun4i-a10-nand";
+       reg = <0x01c03000 0x1000>;
+       interrupts = <0 37 1>;
+       clocks = <&ahb_gates 13>, <&nand_clk>;
+       clock-names = "ahb", "mod";
+       #address-cells = <1>;
+       #size-cells = <0>;
+       pinctrl-names = "default";
+       pinctrl-0 = <&nand_pins_a &nand_cs0_pins_a &nand_rb0_pins_a>;
+       status = "okay";
+
+       nand@0 {
+               reg = <0>;
+               allwinner,rb = <0>;
+               nand-ecc-mode = "soft_bch";
+       };
+};