dt: power: Add docs for generic SYSCON poweroff driver.

Add documentation for generic SYSCON poweroff driver.

Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

diff --git a/Documentation/devicetree/bindings/power/reset/syscon-poweroff.txt b/Documentation/devicetree/bindings/power/reset/syscon-poweroff.txt
new file mode 100644 (file)
index 0000000..1e2546f
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+++ b/Documentation/devicetree/bindings/power/reset/syscon-poweroff.txt
@@ -0,0 +1,23 @@
+Generic SYSCON mapped register poweroff driver
+
+This is a generic poweroff driver using syscon to map the poweroff register.
+The poweroff is generally performed with a write to the poweroff register
+defined by the register map pointed by syscon reference plus the offset
+with the mask defined in the poweroff node.
+
+Required properties:
+- compatible: should contain "syscon-poweroff"
+- regmap: this is phandle to the register map node
+- offset: offset in the register map for the poweroff register (in bytes)
+- mask: the poweroff value written to the poweroff register (32 bit access)
+
+Default will be little endian mode, 32 bit access only.
+
+Examples:
+
+       poweroff {
+          compatible = "syscon-poweroff";
+          regmap = <&regmapnode>;
+          offset = <0x0>;
+          mask = <0x7a>;
+       };