linux-kernel - [PATCH 2/2] hwmon: (max6650) Add initial rpm target devicetree documentation

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

Message-Id: <1472026407-3448-2-git-send-email-mike.looijmans@topic.nl>
Date:   Wed, 24 Aug 2016 10:13:27 +0200
From:   Mike Looijmans <mike.looijmans@...ic.nl>
To:     linux-hwmon@...r.kernel.org, devicetree@...r.kernel.org
Cc:     linux@...ck-us.net, linux-kernel@...r.kernel.org,
        Mike Looijmans <mike.looijmans@...ic.nl>
Subject: [PATCH 2/2] hwmon: (max6650) Add initial rpm target devicetree documentation

Add devicetree property for early initialization of the fan controller
to prevent overheating, for example when resetting the board while the
fan was completely turned off.

Signed-off-by: Mike Looijmans <mike.looijmans@...ic.nl>
---
 Documentation/devicetree/bindings/hwmon/max6650.txt | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/hwmon/max6650.txt b/Documentation/devicetree/bindings/hwmon/max6650.txt
index d6c10e3..f6bd87d 100644
--- a/Documentation/devicetree/bindings/hwmon/max6650.txt
+++ b/Documentation/devicetree/bindings/hwmon/max6650.txt
@@ -13,6 +13,10 @@ Optional properties, default is to retain the chip's current setting:
 - maxim,fan-prescale  : Pre-scaling value, as per datasheet [1]. Lower values
 			allow more fine-grained control of slower fans.
 			Valid: 1, 2, 4, 8, 16.
+- maxim,fan-target-rpm: Initial requested fan rotation speed. If specified, the
+			driver selects closed-loop mode and the requested speed.
+			This ensures the fan is already running before userspace
+			takes over.
 
 Example:
 	fan-max6650: max6650@1b {
@@ -20,4 +24,5 @@ Example:
 		compatible = "maxim,max6650";
 		maxim,fan-microvolt = <12000000>;
 		maxim,fan-prescale = <4>;
+		maxim,fan-target-rpm = <1200>;
 	};
-- 
1.9.1