[PATCH v2 3/8] hwmon: dts: Doc: Add DTS doc to explain how to use PWM FAN as a cooling device

Lukasz Majewski
2014-12-22T16:28:43Z

Several new properties to allow PWM fan working as a cooling device have been
combined into this single commit.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
---
Changes for v2:
- Rename cooling-pwm-values to cooling-levels
- Remove default-pulse-width property and stick to default hwmon policy
---
.../devicetree/bindings/hwmon/pwm-fan.txt | 23 ++++++++++++++++++++++
1 file changed, 23 insertions(+)

diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
index 610757c..001446a 100644
--- a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
+++ b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
@@ -3,10 +3,33 @@ 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-min-state = <0>;
+ cooling-max-state = <3>;
+ #cooling-cells = <2>;
+ cooling-levels = <0 102 170 255>;
};
--
2.0.0.rc2