1*4882a593SmuzhiyunBindings for a fan connected to the PWM lines 2*4882a593Smuzhiyun 3*4882a593SmuzhiyunRequired properties: 4*4882a593Smuzhiyun- compatible : "pwm-fan" 5*4882a593Smuzhiyun- pwms : the PWM that is used to control the PWM fan 6*4882a593Smuzhiyun- cooling-levels : PWM duty cycle values in a range from 0 to 255 7*4882a593Smuzhiyun which correspond to thermal cooling states 8*4882a593Smuzhiyun 9*4882a593SmuzhiyunOptional properties: 10*4882a593Smuzhiyun- fan-supply : phandle to the regulator that provides power to the fan 11*4882a593Smuzhiyun- interrupts : This contains a single interrupt specifier which 12*4882a593Smuzhiyun describes the tachometer output of the fan as an 13*4882a593Smuzhiyun interrupt source. The output signal must generate a 14*4882a593Smuzhiyun defined number of interrupts per fan revolution, which 15*4882a593Smuzhiyun require that it must be self resetting edge interrupts. 16*4882a593Smuzhiyun See interrupt-controller/interrupts.txt for the format. 17*4882a593Smuzhiyun- pulses-per-revolution : define the tachometer pulses per fan revolution as 18*4882a593Smuzhiyun an integer (default is 2 interrupts per revolution). 19*4882a593Smuzhiyun The value must be greater than zero. 20*4882a593Smuzhiyun- rockchip,temp-trips : The property is an array of 2-tuples items, and 21*4882a593Smuzhiyun each item consists of temperature in millicelsius and 22*4882a593Smuzhiyun pwm cooling state. This depends on CONFIG_ROCKCHIP_SYSTEM_MONITOR. 23*4882a593Smuzhiyun If add the property the fan cooling state will be changed 24*4882a593Smuzhiyun by system monitor. Otherwise, use the default thermal governor. 25*4882a593Smuzhiyun 26*4882a593SmuzhiyunExample: 27*4882a593Smuzhiyun fan0: pwm-fan { 28*4882a593Smuzhiyun compatible = "pwm-fan"; 29*4882a593Smuzhiyun #cooling-cells = <2>; 30*4882a593Smuzhiyun pwms = <&pwm 0 10000 0>; 31*4882a593Smuzhiyun cooling-levels = <0 102 170 230>; 32*4882a593Smuzhiyun }; 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun thermal-zones { 35*4882a593Smuzhiyun cpu_thermal: cpu-thermal { 36*4882a593Smuzhiyun thermal-sensors = <&tmu 0>; 37*4882a593Smuzhiyun polling-delay-passive = <0>; 38*4882a593Smuzhiyun polling-delay = <0>; 39*4882a593Smuzhiyun trips { 40*4882a593Smuzhiyun cpu_alert1: cpu-alert1 { 41*4882a593Smuzhiyun temperature = <100000>; /* millicelsius */ 42*4882a593Smuzhiyun hysteresis = <2000>; /* millicelsius */ 43*4882a593Smuzhiyun type = "passive"; 44*4882a593Smuzhiyun }; 45*4882a593Smuzhiyun }; 46*4882a593Smuzhiyun cooling-maps { 47*4882a593Smuzhiyun map0 { 48*4882a593Smuzhiyun trip = <&cpu_alert1>; 49*4882a593Smuzhiyun cooling-device = <&fan0 0 1>; 50*4882a593Smuzhiyun }; 51*4882a593Smuzhiyun }; 52*4882a593Smuzhiyun }; 53*4882a593Smuzhiyun 54*4882a593SmuzhiyunExample 2: 55*4882a593Smuzhiyun fan0: pwm-fan { 56*4882a593Smuzhiyun compatible = "pwm-fan"; 57*4882a593Smuzhiyun pwms = <&pwm 0 40000 0>; 58*4882a593Smuzhiyun fan-supply = <®_fan>; 59*4882a593Smuzhiyun interrupt-parent = <&gpio5>; 60*4882a593Smuzhiyun interrupts = <1 IRQ_TYPE_EDGE_FALLING>; 61*4882a593Smuzhiyun pulses-per-revolution = <2>; 62*4882a593Smuzhiyun }; 63