dt: Move device tree documentation out of powerpc directory

The device tree is used by more than just PowerPC.  Make the documentation
directory available to all.

v2: reorganized files while moving to create arch and driver specific
    directories.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/spi/fsl-spi.txt b/Documentation/devicetree/bindings/spi/fsl-spi.txt
new file mode 100644
index 000000000000..777abd7399d5
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/fsl-spi.txt
@@ -0,0 +1,53 @@
+* SPI (Serial Peripheral Interface)
+
+Required properties:
+- cell-index : QE SPI subblock index.
+		0: QE subblock SPI1
+		1: QE subblock SPI2
+- compatible : should be "fsl,spi".
+- mode : the SPI operation mode, it can be "cpu" or "cpu-qe".
+- reg : Offset and length of the register set for the device
+- interrupts : <a b> where a is the interrupt number and b is a
+  field that represents an encoding of the sense and level
+  information for the interrupt.  This should be encoded based on
+  the information in section 2) depending on the type of interrupt
+  controller you have.
+- interrupt-parent : the phandle for the interrupt controller that
+  services interrupts for this device.
+
+Optional properties:
+- gpios : specifies the gpio pins to be used for chipselects.
+  The gpios will be referred to as reg = <index> in the SPI child nodes.
+  If unspecified, a single SPI device without a chip select can be used.
+
+Example:
+	spi@4c0 {
+		cell-index = <0>;
+		compatible = "fsl,spi";
+		reg = <4c0 40>;
+		interrupts = <82 0>;
+		interrupt-parent = <700>;
+		mode = "cpu";
+		gpios = <&gpio 18 1	// device reg=<0>
+			 &gpio 19 1>;	// device reg=<1>
+	};
+
+
+* eSPI (Enhanced Serial Peripheral Interface)
+
+Required properties:
+- compatible : should be "fsl,mpc8536-espi".
+- reg : Offset and length of the register set for the device.
+- interrupts : should contain eSPI interrupt, the device has one interrupt.
+- fsl,espi-num-chipselects : the number of the chipselect signals.
+
+Example:
+	spi@110000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "fsl,mpc8536-espi";
+		reg = <0x110000 0x1000>;
+		interrupts = <53 0x2>;
+		interrupt-parent = <&mpic>;
+		fsl,espi-num-chipselects = <4>;
+	};