Re: [PATCH v3 3/3] dt-bindings: hwmon: (aspeed,g5-pwm-tacho) Move info from txt to yaml

[Rob Herring <robh@kernel.org>]

On Thu, Dec 04, 2025 at 02:02:36PM -0700, Rebecca Cran wrote:
> Move the documentation for the aspeed,ast2400-pwm-tacho and
> aspeed,ast2500-pwm-tacho devices from a text file to yaml file.
> 
> This allows for dts files containing these devices to be validated.
> 
> Where the text file documenation of required properties differ from the
> implementation, prefer the implementation and update the schema to
> match.
> 
> "#size-cells" was 1 but implementation is 0.
> "#cooling-cells" was marked as required but appears optional.
> 
> In the fan subnode, "cooling-levels" is optional according to the code
> in drivers/hwmon/aspeed-pwm-tacho.c.

Please see this one:

https://lore.kernel.org/all/20251029185448.2121857-1-robh@kernel.org/

> 
> Signed-off-by: Rebecca Cran <rebecca@bsdio.com>
> ---
>  Documentation/devicetree/bindings/hwmon/aspeed,pwm-tacho.yaml | 91 ++++++++++++++++++++
>  Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt  | 73 ----------------
>  2 files changed, 91 insertions(+), 73 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/aspeed,pwm-tacho.yaml b/Documentation/devicetree/bindings/hwmon/aspeed,pwm-tacho.yaml
> new file mode 100644
> index 000000000000..b23c3519604b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/aspeed,pwm-tacho.yaml
> @@ -0,0 +1,91 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2023 Aspeed, Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/aspeed,g5-pwm-tacho.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ASPEED AST2400/AST2500 PWM and Fan Tacho controller
> +
> +maintainers:
> +  - Billy Tsai <billy_tsai@aspeedtech.com>
> +
> +description: |
> +  The ASPEED PWM controller can support up to 8 PWM outputs. The ASPEED Fan
> +  Tacho controller can support up to 16 Fan tachometer inputs.
> +
> +  There can be up to 8 fans supported. Each fan can have one PWM output and
> +  one/two Fan tach inputs.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - aspeed,ast2400-pwm-tacho
> +      - aspeed,ast2500-pwm-tacho
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 0
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  resets:
> +    maxItems: 1
> +
> +patternProperties:
> +  "^fan@[0-9]+$":
> +    $ref: fan-common.yaml#
> +    unevaluatedProperties: false
> +    properties:
> +      aspeed,fan-tach-ch:
> +        description:
> +          The tach channel used for the fan.
> +        $ref: /schemas/types.yaml#/definitions/uint8-array
> +
> +    required:
> +      - reg
> +      - aspeed,fan-tach-ch
> +
> +required:
> +  - compatible
> +  - "#address-cells"
> +  - "#size-cells"
> +  - reg
> +  - pinctrl-names
> +  - pinctrl-0
> +  - clocks
> +  - resets
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/aspeed-clock.h>
> +    pwm_tacho: pwmtachocontroller@1e786000 {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        #cooling-cells = <2>;
> +        reg = <0x1E786000 0x1000>;
> +        compatible = "aspeed,ast2500-pwm-tacho";
> +        clocks = <&syscon ASPEED_CLK_APB>;
> +        resets = <&syscon ASPEED_RESET_PWM>;
> +        pinctrl-names = "default";
> +        pinctrl-0 = <&pinctrl_pwm0_default &pinctrl_pwm1_default>;
> +
> +        fan@0 {
> +                reg = <0x00>;
> +                cooling-levels = /bits/ 8 <125 151 177 203 229 255>;
> +                aspeed,fan-tach-ch = /bits/ 8 <0x00>;
> +        };
> +
> +        fan@1 {
> +                reg = <0x01>;
> +                aspeed,fan-tach-ch = /bits/ 8 <0x01 0x02>;
> +        };
> +    };
> diff --git a/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt b/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt
> deleted file mode 100644
> index 8645cd3b867a..000000000000
> --- a/Documentation/devicetree/bindings/hwmon/aspeed-pwm-tacho.txt
> +++ /dev/null
> @@ -1,73 +0,0 @@
> -ASPEED AST2400/AST2500 PWM and Fan Tacho controller device driver
> -
> -The ASPEED PWM controller can support upto 8 PWM outputs. The ASPEED Fan Tacho
> -controller can support upto 16 Fan tachometer inputs.
> -
> -There can be upto 8 fans supported. Each fan can have one PWM output and
> -one/two Fan tach inputs.
> -
> -Required properties for pwm-tacho node:
> -- #address-cells : should be 1.
> -
> -- #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.
> -
> -- pinctrl-0 : phandle referencing pin configuration of the PWM ports.
> -
> -- compatible : should be "aspeed,ast2400-pwm-tacho" for AST2400 and
> -	       "aspeed,ast2500-pwm-tacho" for AST2500.
> -
> -- clocks : phandle to clock provider with the clock number in the second cell
> -
> -- resets : phandle to reset controller with the reset number in the second cell
> -
> -fan subnode format:
> -===================
> -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.
> -		At least one Fan tach input channel is required.
> -
> -Examples:
> -
> -pwm_tacho: pwmtachocontroller@1e786000 {
> -	#address-cells = <1>;
> -	#size-cells = <1>;
> -	#cooling-cells = <2>;
> -	reg = <0x1E786000 0x1000>;
> -	compatible = "aspeed,ast2500-pwm-tacho";
> -	clocks = <&syscon ASPEED_CLK_APB>;
> -	resets = <&syscon ASPEED_RESET_PWM>;
> -	pinctrl-names = "default";
> -	pinctrl-0 = <&pinctrl_pwm0_default &pinctrl_pwm1_default>;
> -
> -	fan@0 {
> -		reg = <0x00>;
> -		cooling-levels = /bits/ 8 <125 151 177 203 229 255>;
> -		aspeed,fan-tach-ch = /bits/ 8 <0x00>;
> -	};
> -
> -	fan@1 {
> -		reg = <0x01>;
> -		aspeed,fan-tach-ch = /bits/ 8 <0x01 0x02>;
> -	};
> -};
> -- 
> 2.47.3
>