Re: [PATCH v7 1/2] dt-binding: hwmon: Add NPCM7xx PWM and Fan controller documentation

[Rob Herring <robh@kernel.org>]

On Tue, Jul 03, 2018 at 12:47:00PM +0300, Tomer Maimon wrote:
> 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@gmail.com>
> ---
>  .../devicetree/bindings/hwmon/npcm750-pwm-fan.txt  | 87 ++++++++++++++++++++++
>  1 file changed, 87 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..c56d72d03717
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/npcm750-pwm-fan.txt
> @@ -0,0 +1,87 @@
> +Nuvoton NPCM7xx PWM and Fan Tacho controller device
> +
> +The NPCM7xx has two identical Pulse-width modulation (PWM) controller modules,
> +Each PWM module has four PWM controller outputs, Totally 8 PWM controller outputs.

Kind of sounds like this should be 2 nodes then?

> +
> +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
> +- #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
> +					* "clk_apb3" for clock of PWM controller.
> + 					* "clk_apb4" for clock of Fan controller.

The "clk_" part is redundant.

Also, this should be the names of the clocks in the module, not the name 
of the source clocks. It seems like these may be the latter?

> +- 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 = "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>;
> +	fan@0 {
> +		reg = <0x00>;
> +		fan-ch = /bits/ 8 <0x00 0x01>;

Doesn't match the doc.

> +		cooling-levels = <127 255>;
> +	};
> +	fan@1 {
> +		reg = <0x01>;
> +		fan-ch = /bits/ 8 <0x02 0x03>;
> +	};
> +	fan@2 {
> +		reg = <0x02>;
> +		fan-ch = /bits/ 8 <0x04>;
> +	};
> +
> +};
> \ No newline at end of file
> -- 
> 2.14.1
>