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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 17 Apr 2020 19:08:23 +0200
From:   Thierry Reding <thierry.reding@...il.com>
To:     Lee Jones <lee.jones@...aro.org>, Rob Herring <robh+dt@...nel.org>,
        Alessandro Zummo <a.zummo@...ertech.it>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>
Cc:     Jon Hunter <jonathanh@...dia.com>, devicetree@...r.kernel.org,
        linux-rtc@...r.kernel.org, linux-tegra@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 1/3] dt-bindings: mfd: Document the RTC present on MAX77620

From: Thierry Reding <treding@...dia.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@...dia.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