diff mbox

[v5,1/6] Documentation: dts: Documentation entry to explain how to use PWM FAN as a cooling device

Message ID 1424878462-15511-2-git-send-email-l.majewski@samsung.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Lukasz Majewski Feb. 25, 2015, 3:34 p.m. UTC
Explanation of several properties, which allow PWM fan working as a cooling
device, have been embraced in this 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
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
Changes for v4:
- None
Changes for v5:
- Move thermal-zones description to example section
- Extending example section

---
 .../devicetree/bindings/hwmon/pwm-fan.txt          | 25 +++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

Comments

Eduardo Valentin Feb. 25, 2015, 7:11 p.m. UTC | #1
On Wed, Feb 25, 2015 at 04:34:17PM +0100, Lukasz Majewski wrote:
> Explanation of several properties, which allow PWM fan working as a cooling
> device, have been embraced in this 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
> 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
> Changes for v4:
> - None
> Changes for v5:
> - Move thermal-zones description to example section
> - Extending example section
> 
> ---
>  .../devicetree/bindings/hwmon/pwm-fan.txt          | 25 +++++++++++++++++++++-
>  1 file changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
> index 610757c..645251b 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
>  
>  Example:
> -	pwm-fan {
> +	fan0: pwm-fan {
>  		compatible = "pwm-fan";
>  		status = "okay";
>  		pwms = <&pwm 0 10000 0>;
> +		cooling-levels = <0 102 170 230>;
> +	};
> +
> +	thermal-zones {
> +		cpu_thermal: cpu-thermal {
> +		cooling-min-state = <0>;
> +		cooling-max-state = <3>;
> +		#cooling-cells = <2>;
> +		trips {
> +			cpu_alert1: cpu-alert1 {
> +				temperature = <100000>; /* millicelsius */
> +				hysteresis = <2000>; /* millicelsius */
> +				type = "passive";
> +			};
> +		};
> +		cooling-maps {
> +			map0 {
> +			     trip = <&cpu_alert1>;
> +			     cooling-device = <&fan0 0 1>;
> +			};
> +		};

The above example has two issues:
(1) it is wrong, as the cooling device properties are in the thermal
zone node.
(2) has a misalignment / tabulation

Can you please fix that in your next version too?

>  	};
> -- 
> 2.0.0.rc2
>
Eduardo Valentin Feb. 25, 2015, 7:13 p.m. UTC | #2
On Wed, Feb 25, 2015 at 03:11:24PM -0400, Eduardo Valentin wrote:
> On Wed, Feb 25, 2015 at 04:34:17PM +0100, Lukasz Majewski wrote:
> > Explanation of several properties, which allow PWM fan working as a cooling
> > device, have been embraced in this 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
> > 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
> > Changes for v4:
> > - None
> > Changes for v5:
> > - Move thermal-zones description to example section
> > - Extending example section
> > 
> > ---
> >  .../devicetree/bindings/hwmon/pwm-fan.txt          | 25 +++++++++++++++++++++-
> >  1 file changed, 24 insertions(+), 1 deletion(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
> > index 610757c..645251b 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
> >  
> >  Example:
> > -	pwm-fan {
> > +	fan0: pwm-fan {
> >  		compatible = "pwm-fan";
> >  		status = "okay";
> >  		pwms = <&pwm 0 10000 0>;
> > +		cooling-levels = <0 102 170 230>;
> > +	};
> > +
> > +	thermal-zones {
> > +		cpu_thermal: cpu-thermal {
> > +		cooling-min-state = <0>;
> > +		cooling-max-state = <3>;
> > +		#cooling-cells = <2>;
> > +		trips {
> > +			cpu_alert1: cpu-alert1 {
> > +				temperature = <100000>; /* millicelsius */
> > +				hysteresis = <2000>; /* millicelsius */
> > +				type = "passive";
> > +			};
> > +		};
> > +		cooling-maps {
> > +			map0 {
> > +			     trip = <&cpu_alert1>;
> > +			     cooling-device = <&fan0 0 1>;
> > +			};
> > +		};
> 
> The above example has two issues:
> (1) it is wrong, as the cooling device properties are in the thermal
> zone node.
> (2) has a misalignment / tabulation
> 
> Can you please fix that in your next version too?


Apart from the above two issues you may add my 
Acked-by: Eduardo Valentin <edubezval@gmail.com>

> 
> >  	};
> > -- 
> > 2.0.0.rc2
> >
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
index 610757c..645251b 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
 
 Example:
-	pwm-fan {
+	fan0: pwm-fan {
 		compatible = "pwm-fan";
 		status = "okay";
 		pwms = <&pwm 0 10000 0>;
+		cooling-levels = <0 102 170 230>;
+	};
+
+	thermal-zones {
+		cpu_thermal: cpu-thermal {
+		cooling-min-state = <0>;
+		cooling-max-state = <3>;
+		#cooling-cells = <2>;
+		trips {
+			cpu_alert1: cpu-alert1 {
+				temperature = <100000>; /* millicelsius */
+				hysteresis = <2000>; /* millicelsius */
+				type = "passive";
+			};
+		};
+		cooling-maps {
+			map0 {
+			     trip = <&cpu_alert1>;
+			     cooling-device = <&fan0 0 1>;
+			};
+		};
 	};