Re: [v6 1/2] dt-bindings: Add bindings for aspeed pwm-tach.

[Rob Herring <robh@kernel.org>]

On Tue, May 18, 2021 at 08:55:16AM +0800, Billy Tsai wrote:
> This patch adds device binding for aspeed pwm-tach device which is a
> multi-function device include pwm and tach function and pwm/tach device
> bindings which should be the child-node of pwm-tach device.
> 
> Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
> ---
>  .../bindings/hwmon/aspeed,ast2600-tach.yaml   | 66 +++++++++++++++
>  .../bindings/mfd/aspeed,ast2600-pwm-tach.yaml | 84 +++++++++++++++++++
>  .../bindings/pwm/aspeed,ast2600-pwm.yaml      | 62 ++++++++++++++
>  3 files changed, 212 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwmon/aspeed,ast2600-tach.yaml
>  create mode 100644 Documentation/devicetree/bindings/mfd/aspeed,ast2600-pwm-tach.yaml
>  create mode 100644 Documentation/devicetree/bindings/pwm/aspeed,ast2600-pwm.yaml
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/aspeed,ast2600-tach.yaml b/Documentation/devicetree/bindings/hwmon/aspeed,ast2600-tach.yaml
> new file mode 100644
> index 000000000000..0b23281e9f5c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/aspeed,ast2600-tach.yaml
> @@ -0,0 +1,66 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2021 ASPEED, Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwmon/aspeed,ast2600-tach.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ASPEED AST2600 Tach controller
> +
> +maintainers:
> +  - Billy Tsai <billy_tsai@aspeedtech.com>
> +
> +description: |
> +  The ASPEED Tach controller can support upto 16 fan input.
> +  This module is part of the ast2600-pwm-tach multi-function device. For more
> +  details see ../mfd/aspeed,ast2600-pwm-tach.yaml.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - aspeed,ast2600-tach
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 0
> +
> +  pinctrl-0: true
> +
> +  pinctrl-names:
> +    const: default
> +
> +
> +required:
> +  - compatible
> +  - "#address-cells"
> +  - "#size-cells"
> +
> +additionalProperties:
> +  type: object
> +  properties:
> +    reg:
> +      description:
> +        The tach channel used for this fan.
> +      maxItems: 1

blank line between each DT property sub-schema please.

> +    aspeed,min-rpm:
> +      description:
> +        define the minimal revolutions per minute of the measure fan
> +        used to calculate the sample period of tach
> +      default: 1000
> +    aspeed,pulse-pr:
> +      description:
> +        Value specifying the number of pulses per revolution of the
> +        monitored FAN.
> +      default: 2
> +    aspeed,tach-div:
> +      description:
> +        define the tachometer clock divider as an integer. Formula of
> +        tach clock = clock source / (2^tach-div)^2
> +      minimum: 0
> +      maximum: 15
> +      # The value that should be used if the property is not present
> +      default: 5
> +  required:
> +    - reg
> diff --git a/Documentation/devicetree/bindings/mfd/aspeed,ast2600-pwm-tach.yaml b/Documentation/devicetree/bindings/mfd/aspeed,ast2600-pwm-tach.yaml
> new file mode 100644
> index 000000000000..d742ccfcc003
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/aspeed,ast2600-pwm-tach.yaml
> @@ -0,0 +1,84 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2021 ASPEED, Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/aspeed,ast2600-pwm-tach.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: PWM Tach controller Device Tree Bindings
> +
> +description: |
> +  The PWM Tach controller is represented as a multi-function device which
> +  includes:
> +    PWM
> +    Tach
> +
> +maintainers:
> +  - Billy Tsai <billy_tsai@aspeedtech.com>
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - aspeed,ast2600-pwm-tach
> +      - const: syscon
> +      - const: simple-mfd
> +  reg:
> +    maxItems: 1
> +  clocks:
> +    maxItems: 1
> +  resets:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - resets
> +
> +patternProperties:
> +  "^pwm(@[0-9a-f]+)?$":
> +    $ref: ../pwm/aspeed,ast2600-pwm.yaml
> +
> +  "^tach(@[0-9a-f]+)?$":
> +    $ref: ../hwmon/aspeed,ast2600-tach.yaml
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/ast2600-clock.h>
> +    pwm_tach: pwm_tach@1e610000 {
> +      compatible = "aspeed,ast2600-pwm-tach", "syscon", "simple-mfd";
> +      reg = <0x1e610000 0x100>;
> +      clocks = <&syscon ASPEED_CLK_AHB>;
> +      resets = <&syscon ASPEED_RESET_PWM>;
> +
> +      pwm: pwm {
> +        compatible = "aspeed,ast2600-pwm";
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        #pwm-cells = <3>;
> +        pinctrl-names = "default";
> +        pinctrl-0 = <&pinctrl_pwm0_default>;
> +        pwm-ch@0 {
> +          reg = <0>;
> +          aspeed,wdt-reload-enable;
> +          aspeed,wdt-reload-duty-point = <32>;

Normally, you configure the PWM on the client side, not the producer 
side.

> +        };
> +      };
> +
> +      tach: tach {
> +        compatible = "aspeed,ast2600-tach";

Are pwm and tach separate h/w blocks? 

> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        pinctrl-names = "default";
> +        pinctrl-0 = <&pinctrl_tach0_default>;
> +        fan@0 {
> +          reg = <0>;

How does one configure which PWM is connected to each fan?

Existing bindings use 'reg' for PWM channel and another property for 
tach channel. Please don't do something different.

> +          aspeed,min-rpm = <1000>;
> +          aspeed,pulse-pr = <2>;
> +          aspeed,tach-div = <5>;
> +        };
> +      };
> +    };
> diff --git a/Documentation/devicetree/bindings/pwm/aspeed,ast2600-pwm.yaml b/Documentation/devicetree/bindings/pwm/aspeed,ast2600-pwm.yaml
> new file mode 100644
> index 000000000000..f1354c8d35b5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pwm/aspeed,ast2600-pwm.yaml
> @@ -0,0 +1,62 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2021 ASPEED, Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pwm/aspeed,ast2600-pwm.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ASPEED AST2600 PWM controller
> +
> +maintainers:
> +  - Billy Tsai <billy_tsai@aspeedtech.com>
> +
> +description: |
> +  The ASPEED PWM controller can support upto 16 PWM outputs.
> +  This module is part of the ast2600-pwm-tach multi-function device. For more
> +  details see ../mfd/aspeed,ast2600-pwm-tach.yaml.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - aspeed,ast2600-pwm
> +
> +  "#pwm-cells":
> +    const: 3
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 0
> +
> +  pinctrl-0: true
> +
> +  pinctrl-names:
> +    const: default
> +
> +
> +required:
> +  - compatible
> +  - "#pwm-cells"
> +  - "#address-cells"
> +  - "#size-cells"
> +
> +additionalProperties:
> +  description: Set extend properties for each pwm channel.
> +  type: object
> +  properties:
> +    reg:
> +      description:
> +        The pwm channel index.
> +      maxItems: 1
> +    aspeed,wdt-reload-enable:
> +      type: boolean
> +      description:
> +        Enable the function of wdt reset reload duty point.
> +    aspeed,wdt-reload-duty-point:
> +      description:
> +        Define the duty point after wdt reset, 0 = 100%
> +      minimum: 0
> +      maximum: 255
> +  required:
> +    - reg
> -- 
> 2.25.1
>