From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Majewski Subject: [PATCH v3 3/8] Documentation: dts: Documentation entry to explain how to use PWM FAN as a cooling device Date: Fri, 06 Feb 2015 17:59:03 +0100 Message-ID: <1423241948-31981-4-git-send-email-l.majewski@samsung.com> References: <1418897591-18332-1-git-send-email-l.majewski@samsung.com> <1423241948-31981-1-git-send-email-l.majewski@samsung.com> Return-path: In-reply-to: <1423241948-31981-1-git-send-email-l.majewski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org To: Eduardo Valentin , Kamil Debski , Jean Delvare , Guenter Roeck , Kukjin Kim Cc: lm-sensors@lm-sensors.org, Linux PM list , "linux-samsung-soc@vger.kernel.org" , devicetree@vger.kernel.org, Lukasz Majewski , Kukjin Kim , linux-kernel@vger.kernel.org, Sjoerd Simons , Abhilash Kesavan , Abhilash Kesavan , Lukasz Majewski List-Id: devicetree@vger.kernel.org Explanation of several properties, which allow PWM fan working as a cooling device, have been embraced in this commit. Signed-off-by: Lukasz Majewski --- Changes for v2: - Rename cooling-pwm-values to cooling-levels - Remove default-pulse-width property and stick to default hwmon policy Changes for v3: - Changing commit title from "hwmon: dts: Doc:" to "Documentation: dts" - Remove unnecessary properties - Set maximal cooling level to 230 instead of 255 --- Documentation/devicetree/bindings/hwmon/pwm-fan.txt | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt index 610757c..d53fe0c 100644 --- a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt +++ b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt @@ -3,10 +3,30 @@ Bindings for a fan connected to the PWM lines Required properties: - compatible : "pwm-fan" - pwms : the PWM that is used to control the PWM fan +- cooling-levels : PWM duty cycle values in a range from 0 to 255 + which correspond to thermal cooling states + +Thorough description of the following bindings: + cooling-min-state = <0>; + cooling-max-state = <3>; + #cooling-cells = <2>; + thermal-zone { + cpu_thermal: cpu-thermal { + cooling-maps { + map0 { + trip = <&cpu_alert1>; + cooling-device = <&fan0 0 1>; + }; + }; + }; + +for PWM FAN used as cooling device can be found at: +./Documentation/devicetree/bindings/thermal/thermal.txt Example: pwm-fan { compatible = "pwm-fan"; status = "okay"; pwms = <&pwm 0 10000 0>; + cooling-levels = <0 102 170 230>; }; -- 2.0.0.rc2