dt-bindings: power: reset: add document for NVMEM based reboot-mode

Add the device tree bindings document for the NVMEM based reboot-mode
driver.

Signed-off-by: Nandor Han <nandor.han@vaisala.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

diff --git a/Documentation/devicetree/bindings/power/reset/nvmem-reboot-mode.txt b/Documentation/devicetree/bindings/power/reset/nvmem-reboot-mode.txt
new file mode 100644 (file)
index 0000000..752d612
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/nvmem-reboot-mode.txt
@@ -0,0 +1,26 @@
+NVMEM reboot mode driver
+
+This driver gets reboot mode magic value from reboot-mode driver
+and stores it in a NVMEM cell named "reboot-mode". Then the bootloader
+can read it and take different action according to the magic
+value stored.
+
+Required properties:
+- compatible: should be "nvmem-reboot-mode".
+- nvmem-cells: A phandle to the reboot mode provided by a nvmem device.
+- nvmem-cell-names: Should be "reboot-mode".
+
+The rest of the properties should follow the generic reboot-mode description
+found in reboot-mode.txt
+
+Example:
+       reboot-mode {
+               compatible = "nvmem-reboot-mode";
+               nvmem-cells = <&reboot_mode>;
+               nvmem-cell-names = "reboot-mode";
+
+               mode-normal     = <0xAAAA5501>;
+               mode-bootloader = <0xBBBB5500>;
+               mode-recovery   = <0xCCCC5502>;
+               mode-test       = <0xDDDD5503>;
+       };