[PATCH V9] thermal: bcm2835: add thermal driver for bcm2835 soc

Stefan Wahren stefan.wahren at i2se.com
Sat Feb 4 01:36:23 PST 2017


Hi Eduardo,

> Eduardo Valentin <edubezval at gmail.com> hat am 2. Februar 2017 um 05:29 geschrieben:
> 
> 
> Hello Martin,
> 
> ...
> 
> 
> #include <dt-bindings/thermal/thermal.h>
> 
> ocp {
> 	...
> 	/*
> 	 * A simple IC with several bandgap temperature sensors.
> 	 */
> 	bandgap0: bandgap at 0x0000ED00 {
> 		...
> 		#thermal-sensor-cells = <1>;
> 	};
> };
> 
> thermal-zones {
> 	cpu_thermal: cpu-thermal {
> 		polling-delay-passive = <250>; /* milliseconds */
> 		polling-delay = <1000>; /* milliseconds */
> 
> 				/* sensor       ID */
> 		thermal-sensors = <&bandgap0     0>;
> 
> 		trips {
> 			/* each zone within the SoC may have its own trips */
> 			cpu_alert: cpu-alert {
> 				temperature = <100000>; /* millicelsius */
> 				hysteresis = <2000>; /* millicelsius */
> 				type = "passive";
> 			};
> 			cpu_crit: cpu-crit {
> 				temperature = <125000>; /* millicelsius */
> 				hysteresis = <2000>; /* millicelsius */
> 				type = "critical";
> 			};
> 		};
> 
> 		cooling-maps {
> 			/* each zone within the SoC may have its own cooling */
> 			...
> 		};
> 	};
> 

if i get it right the device tree binding requires also a cooling map. But how should we model this without a fan or a DVFS driver? Is there something like a placeholder? Do you have an example?

Regards
Stefan



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