Documentation: atmel-quadspi: add binding file for Atmel QSPI driver

This patch documents the DT bindings for the driver of the Atmel QSPI
controller embedded inside sama5d2x SoCs.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

diff --git a/Documentation/devicetree/bindings/mtd/atmel-quadspi.txt b/Documentation/devicetree/bindings/mtd/atmel-quadspi.txt
new file mode 100644 (file)
index 0000000..4898070
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/atmel-quadspi.txt
@@ -0,0 +1,32 @@
+* Atmel Quad Serial Peripheral Interface (QSPI)
+
+Required properties:
+- compatible:     Should be "atmel,sama5d2-qspi".
+- reg:            Should contain the locations and lengths of the base registers
+                  and the mapped memory.
+- reg-names:      Should contain the resource reg names:
+                  - qspi_base: configuration register address space
+                  - qspi_mmap: memory mapped address space
+- interrupts:     Should contain the interrupt for the device.
+- clocks:         The phandle of the clock needed by the QSPI controller.
+- #address-cells: Should be <1>.
+- #size-cells:    Should be <0>.
+
+Example:
+
+spi@f0020000 {
+       compatible = "atmel,sama5d2-qspi";
+       reg = <0xf0020000 0x100>, <0xd0000000 0x8000000>;
+       reg-names = "qspi_base", "qspi_mmap";
+       interrupts = <52 IRQ_TYPE_LEVEL_HIGH 7>;
+       clocks = <&spi0_clk>;
+       #address-cells = <1>;
+       #size-cells = <0>;
+       pinctrl-names = "default";
+       pinctrl-0 = <&pinctrl_spi0_default>;
+       status = "okay";
+
+       m25p80@0 {
+               ...
+       };
+};