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+Nuvoton NPCM7xx PWM and Fan Tacho controller device
+
+The Nuvoton BMC NPCM7XX supports 8 Pulse-width modulation (PWM)
+controller outputs and 16 Fan tachometer controller inputs.
+
+Required properties for pwm-fan node
+- #address-cells : should be 1.
+- #size-cells : should be 0.
+- compatible : "nuvoton,npcm750-pwm-fan" for Poleg NPCM7XX.
+- reg : specifies physical base address and size of the registers.
+- reg-names : must contain:
+ * "pwm" for the PWM registers.
+ * "fan" for the Fan registers.
+- clocks : phandle of reference clocks.
+- clock-names : must contain
+ * "pwm" for PWM controller operating clock.
+ * "fan" for Fan controller operating clock.
+- interrupts : contain the Fan interrupts with flags for falling edge.
+- pinctrl-names : a pinctrl state named "default" must be defined.
+- pinctrl-0 : phandle referencing pin configuration of the PWM and Fan
+ controller ports.
+
+fan subnode format:
+===================
+Under fan subnode can be upto 8 child nodes, each child node representing a fan.
+Each fan subnode must have one PWM channel and atleast one Fan tach channel.
+
+For PWM channel 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 : specify the PWM output channel.
+ integer value in the range 0 through 7, that represent
+ the PWM channel number that used.
+
+- fan-tach-ch : specify the Fan tach input channel.
+ integer value in the range 0 through 15, that represent
+ the fan tach channel number that used.
+
+ At least one Fan tach input channel is required
+
+Optional property for each child node:
+- cooling-levels: PWM duty cycle values in a range from 0 to 255
+ which correspond to thermal cooling states.
+
+Examples:
+
+pwm_fan:pwm-fan-controller@103000 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "nuvoton,npcm750-pwm-fan";
+ reg = <0x103000 0x2000>,
+ <0x180000 0x8000>;
+ reg-names = "pwm", "fan";
+ clocks = <&clk NPCM7XX_CLK_APB3>,
+ <&clk NPCM7XX_CLK_APB4>;
+ clock-names = "pwm","fan";
+ interrupts = <GIC_SPI 96 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 97 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 98 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 99 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 100 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 101 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 102 IRQ_TYPE_LEVEL_HIGH>,
+ <GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pwm0_pins &pwm1_pins &pwm2_pins
+ &fanin0_pins &fanin1_pins &fanin2_pins
+ &fanin3_pins &fanin4_pins>;
+ fan@0 {
+ reg = <0x00>;
+ fan-tach-ch = /bits/ 8 <0x00 0x01>;
+ cooling-levels = <127 255>;
+ };
+ fan@1 {
+ reg = <0x01>;
+ fan-tach-ch = /bits/ 8 <0x02 0x03>;
+ };
+ fan@2 {
+ reg = <0x02>;
+ fan-tach-ch = /bits/ 8 <0x04>;
+ };
+
+};