Re: [PATCH v1 3/3] dt-bindings: riscv: convert pwm bindings to json-schema

[Rob Herring]

On Thu, Sep 10, 2020 at 04:14:04PM +0530, Sagar Kadam wrote:
> Convert device tree bindings for SiFive's PWM controller to YAML
> format.
> 
> Signed-off-by: Sagar Kadam <sagar.kadam@xxxxxxxxxx>
> ---
>  .../devicetree/bindings/pwm/pwm-sifive.txt         | 33 ----------
>  .../devicetree/bindings/pwm/pwm-sifive.yaml        | 72 ++++++++++++++++++++++
>  2 files changed, 72 insertions(+), 33 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/pwm/pwm-sifive.txt
>  create mode 100644 Documentation/devicetree/bindings/pwm/pwm-sifive.yaml
> 
> diff --git a/Documentation/devicetree/bindings/pwm/pwm-sifive.txt b/Documentation/devicetree/bindings/pwm/pwm-sifive.txt
> deleted file mode 100644
> index 3d1dd7b0..0000000
> --- a/Documentation/devicetree/bindings/pwm/pwm-sifive.txt
> +++ /dev/null
> @@ -1,33 +0,0 @@
> -SiFive PWM controller
> -
> -Unlike most other PWM controllers, the SiFive PWM controller currently only
> -supports one period for all channels in the PWM. All PWMs need to run at
> -the same period. The period also has significant restrictions on the values
> -it can achieve, which the driver rounds to the nearest achievable period.
> -PWM RTL that corresponds to the IP block version numbers can be found
> -here:
> -
> -https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/pwm
> -
> -Required properties:
> -- compatible: Should be "sifive,<chip>-pwm" and "sifive,pwm<version>".
> -  Supported compatible strings are: "sifive,fu540-c000-pwm" for the SiFive
> -  PWM v0 as integrated onto the SiFive FU540 chip, and "sifive,pwm0" for the
> -  SiFive PWM v0 IP block with no chip integration tweaks.
> -  Please refer to sifive-blocks-ip-versioning.txt for details.
> -- reg: physical base address and length of the controller's registers
> -- clocks: Should contain a clock identifier for the PWM's parent clock.
> -- #pwm-cells: Should be 3. See pwm.yaml in this directory
> -  for a description of the cell format.
> -- interrupts: one interrupt per PWM channel
> -
> -Examples:
> -
> -pwm:  pwm@10020000 {
> -	compatible = "sifive,fu540-c000-pwm", "sifive,pwm0";
> -	reg = <0x0 0x10020000 0x0 0x1000>;
> -	clocks = <&tlclk>;
> -	interrupt-parent = <&plic>;
> -	interrupts = <42 43 44 45>;
> -	#pwm-cells = <3>;
> -};
> diff --git a/Documentation/devicetree/bindings/pwm/pwm-sifive.yaml b/Documentation/devicetree/bindings/pwm/pwm-sifive.yaml
> new file mode 100644
> index 0000000..415d053
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pwm/pwm-sifive.yaml
> @@ -0,0 +1,72 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (C) 2020 SiFive, Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pwm/pwm-sifive.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SiFive PWM controller
> +
> +maintainers:
> +  - Yash Shah <yash.shah@xxxxxxxxxx>
> +  - Sagar Kadam <sagar.kadam@xxxxxxxxxx>
> +  - Paul Walmsley <paul.walmsley@xxxxxxxxxx>
> +
> +description:
> +  Unlike most other PWM controllers, the SiFive PWM controller currently
> +  only supports one period for all channels in the PWM. All PWMs need to
> +  run at the same period. The period also has significant restrictions on
> +  the values it can achieve, which the driver rounds to the nearest
> +  achievable period. PWM RTL that corresponds to the IP block version
> +  numbers can be found here -
> +
> +  https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/pwm
> +
> +properties:
> +  compatible:
> +    items:
> +      - const: sifive,fu540-c000-pwm
> +      - const: sifive,pwm0
> +    description:
> +      Should be "sifive,<chip>-pwm" and "sifive,pwm<version>". Supported
> +      compatible strings are "sifive,fu540-c000-pwm" for the SiFive PWM v0
> +      as integrated onto the SiFive FU540 chip, and "sifive,pwm0" for the
> +      SiFive PWM v0 IP block with no chip integration tweaks.
> +      Please refer to sifive-blocks-ip-versioning.txt for details.
> +
> +  reg:
> +    maxItems: 1
> +    description: Physical base address and length of the controller's registers

Drop description.

> +
> +  clocks:
> +    description: Should contain a clock identifier for the PWM's parent clock.

How many clocks?

> +
> +  "#pwm-cells":
> +    const: 3
> +    description:
> +      Should be 3. See pwm.yaml in this directory for a description of the
> +      cell format.

Drop.

> +
> +  interrupts:
> +    maxItems: 1

Is it 1 or...

> +    description: One interrupt per PWM channel.

one per channel?

> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - "#pwm-cells"
> +  - interrupts
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    pwm:  pwm@10020000 {
> +      compatible = "sifive,fu540-c000-pwm", "sifive,pwm0";
> +      reg = <0x10020000 0x1000>;
> +      clocks = <&tlclk>;
> +      interrupt-parent = <&plic>;
> +      interrupts = <42 43 44 45>;

Split entries:

interrupts = <42>, <43>, <44>, <45>;

> +      #pwm-cells = <3>;
> +    };
> -- 
> 2.7.4
>