[PATCH 1/3] dt-bindings: mfd: Document the RTC present on MAX77620

[Thierry Reding <thierry.reding@gmail.com>]

From: Thierry Reding <treding@nvidia.com>

The RTC present on MAX77620 can be used to generate an alarm at a given
time, which in turn can be used as a wakeup source for the system if it
is properly wired up.

Document how to enable the RTC to act as a wakeup source.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
 .../devicetree/bindings/mfd/max77620.txt          | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/max77620.txt b/Documentation/devicetree/bindings/mfd/max77620.txt
index 5a642a51d58e..f05005b0993e 100644
--- a/Documentation/devicetree/bindings/mfd/max77620.txt
+++ b/Documentation/devicetree/bindings/mfd/max77620.txt
@@ -125,6 +125,17 @@ MAX77663 supports 20, 40, 80, 160, 320, 640, 1280 and 2540 microseconds.
 			control) then, GPIO1/nRST_IO goes LOW.
 			this property is valid for max20024 only.
 
+Realtime Clock
+--------------
+The MAX77620 family of power management ICs contain a realtime clock block
+that can be used to keep track of time even when the system is powered off.
+
+The realtime clock can also be programmed to trigger alerts, which can be
+used to wake the system up from sleep. In order to configure the RTC to act
+as a wakeup source, add an "rtc" child node and add the "wakeup-source"
+property.
+
+
 For DT binding details of different sub modules like GPIO, pincontrol,
 regulator, power, please refer respective device-tree binding document
 under their respective sub-system directories.
@@ -159,4 +170,8 @@ max77620@3c {
 			maxim,fps-event-source = <MAX77620_FPS_EVENT_SRC_SW>;
 		};
 	};
+
+	rtc {
+		wakeup-source;
+	};
 };
-- 
2.24.1