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+GPIO assisted NAND flash
+
+The GPIO assisted NAND flash uses a memory mapped interface to
+read/write the NAND commands and data and GPIO pins for the control
+signals.
+
+Required properties:
+- compatible : "gpio-control-nand"
+- reg : should specify localbus chip select and size used for the chip. The
+ resource describes the data bus connected to the NAND flash and all accesses
+ are made in native endianness.
+- #address-cells, #size-cells : Must be present if the device has sub-nodes
+ representing partitions.
+- gpios : Specifies the GPIO pins to control the NAND device. The order of
+ GPIO references is: RDY, nCE, ALE, CLE, and an optional nWP.
+
+Optional properties:
+- bank-width : Width (in bytes) of the device. If not present, the width
+ defaults to 1 byte.
+- chip-delay : chip dependent delay for transferring data from array to
+ read registers (tR). If not present then a default of 20us is used.
+- gpio-control-nand,io-sync-reg : A 64-bit physical address for a read
+ location used to guard against bus reordering with regards to accesses to
+ the GPIO's and the NAND flash data bus. If present, then after changing
+ GPIO state and before and after command byte writes, this register will be
+ read to ensure that the GPIO accesses have completed.
+
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
+
+Examples:
+
+gpio-nand@1,0 {
+ compatible = "gpio-control-nand";
+ reg = <1 0x0000 0x2>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ gpios = <&banka 1 0>, /* RDY */
+ <&banka 2 0>, /* nCE */
+ <&banka 3 0>, /* ALE */
+ <&banka 4 0>, /* CLE */
+ <0>; /* nWP */
+
+ partition@0 {
+ ...
+ };
+};