[PATCH v3 1/2] dt-binding: hwmon: Add NPCM7xx PWM and Fan controller documentation

[Tomer Maimon]

Added device tree binding documentation for Nuvoton BMC
NPCM7xx Pulse Width Modulation (PWM)  and Fan tach controller.
The PWM controller can support upto 8 PWM output ports.
The Fan tach controller can support upto 16 tachometer inputs.

Signed-off-by: Tomer Maimon <tmaimon77 at gmail.com>
---
 .../devicetree/bindings/hwmon/npcm750-pwm-fan.txt  | 84 ++++++++++++++++++++++
 1 file changed, 84 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/npcm750-pwm-fan.txt

diff --git a/Documentation/devicetree/bindings/hwmon/npcm750-pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/npcm750-pwm-fan.txt
new file mode 100644
index 000000000000..a9eacda34f92
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/npcm750-pwm-fan.txt
@@ -0,0 +1,84 @@
+Nuvoton NPCM7xx PWM and Fan Tacho controller device driver
+
+The NPCM7xx has two identical Pulse-width modulation (PWM) controller modules,
+Each PWM module has four PWM controller outputs, Totally 8 PWM controller outputs.
+
+The NPCM7xx has eight identical Fan tachometer controller modules,
+Each Fan module has two Fan controller inputs, Totally 16 Fan controller inputs.
+
+Required properties for pwm-fan node:
+- compatible	: "nuvoton,npcm750-pwm-fan" for Poleg NPCM7XX.
+- reg 			: specifies physical base address and size of the registers.
+- reg-names 	: must contain:
+					* "pwm-base" for the PWM registers.
+ 					* "fan-base" for the Fan registers.
+- clocks		: phandle of reference clocks.
+- clock-names	: must contain
+					* "clk_apb3" for clock of PWM controller.
+ 					* "clk_apb4" for clock of Fan controller.
+- 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.
+
+pwm subnode format:
+===================
+Under pwm subnode can be upto 8 child nodes, each child node representing a PWM channel.
+Each pwm 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:
+- pwm-ch : specify the PWM output channel.
+			integer value in the range 0 through 7, that represent
+			the PWM channel number that used.
+
+- fan-ch : specify the Fan input channel.
+			integer value in the range 0 through 15, that represent
+			the Fan 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 at 103000 {
+	compatible = "nuvoton,npcm750-pwm-fan";
+	reg = <0x103000 0x2000>,
+		<0x180000 0x8000>;
+	reg-names = "pwm_base", "fan_base";
+	clocks = <&clk NPCM7XX_CLK_APB3>,
+		<&clk NPCM7XX_CLK_APB4>;
+	clock-names = "clk_apb3","clk_apb4";
+	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>;
+
+			pwm at 0 {
+				pwm-ch = /bits/ 8 <0x00>;
+				fan-ch = /bits/ 8 <0x00 0x01>;
+				cooling-levels = <127 255>;
+				};
+			pwm at 1 {
+				pwm-ch = /bits/ 8 <0x01>;
+				fan-ch = /bits/ 8 <0x02 0x03>;
+				};
+			pwm at 2 {
+				pwm-ch = /bits/ 8 <0x02>;
+				fan-ch = /bits/ 8 <0x04>;
+				};
+
+};
\ No newline at end of file
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