- #size-cells : should be 1.
+- #cooling-cells: should be 2.
+
- reg : address and length of the register set for the device.
- pinctrl-names : a pinctrl state named "default" must be defined.
Under fan subnode there can upto 8 child nodes, with each child node
representing a fan. If there are 8 fans each fan can have one PWM port and
one/two Fan tach inputs.
+For PWM port can be configured cooling-levels to create cooling device.
+Cooling device could be bound to a thermal zone for the thermal control.
Required properties for each child node:
- reg : should specify PWM source port.
integer value in the range 0 to 7 with 0 indicating PWM port A and
7 indicating PWM port H.
+- cooling-levels: PWM duty cycle values in a range from 0 to 255
+ which correspond to thermal cooling states.
+
- aspeed,fan-tach-ch : should specify the Fan tach input channel.
integer value in the range 0 through 15, with 0 indicating
Fan tach channel 0 and 15 indicating Fan tach channel 15.
pwm_tacho: pwmtachocontroller@1e786000 {
#address-cells = <1>;
#size-cells = <1>;
+ #cooling-cells = <2>;
reg = <0x1E786000 0x1000>;
compatible = "aspeed,ast2500-pwm-tacho";
clocks = <&pwm_tacho_fixed_clk>;
fan@0 {
reg = <0x00>;
+ cooling-levels = /bits/ 8 <125 151 177 203 229 255>;
aspeed,fan-tach-ch = /bits/ 8 <0x00>;
};