Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / devicetree / bindings / mtd / gpio-control-nand.txt

diff --git a/kernel/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt b/kernel/Documentation/devicetree/bindings/mtd/gpio-control-nand.txt
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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 {
+       ...
+       };
+};