Re: [PATCH v2 1/9] dt-bindings: atmel-tcb: convert bindings to json-schema

[Rob Herring]

On Wed, Apr 15, 2020 at 11:48:18AM +0200, Alexandre Belloni wrote:
> Convert Atmel Timer Counter Blocks bindings to DT schema format using
> json-schema.
> 
> Also move it out of mfd as it is not and has never been related to mfd.
> 
> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> ---
> Cc: Rob Herring <robh+dt@xxxxxxxxxx>
> 
> Changes in v2:
>  - Rebased on v5.7-rc1
>  - Moved the binding documentation to its proper place
>  - Added back the atmel,tcb-timer child node documentation
> 
>  .../devicetree/bindings/mfd/atmel-tcb.txt     | 56 ------------
>  .../soc/microchip/atmel,at91rm9200-tcb.yaml   | 89 +++++++++++++++++++
>  .../bindings/timer/atmel,tcb-timer.yaml       | 51 +++++++++++
>  3 files changed, 140 insertions(+), 56 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/mfd/atmel-tcb.txt
>  create mode 100644 Documentation/devicetree/bindings/soc/microchip/atmel,at91rm9200-tcb.yaml
>  create mode 100644 Documentation/devicetree/bindings/timer/atmel,tcb-timer.yaml


> diff --git a/Documentation/devicetree/bindings/soc/microchip/atmel,at91rm9200-tcb.yaml b/Documentation/devicetree/bindings/soc/microchip/atmel,at91rm9200-tcb.yaml
> new file mode 100644
> index 000000000000..2522fb1f4ce4
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/microchip/atmel,at91rm9200-tcb.yaml
> @@ -0,0 +1,89 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/soc/microchip/atmel,at91rm9200-tcb.yaml#";
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#";
> +
> +title: Atmel Timer Counter Block
> +
> +maintainers:
> +  - Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> +
> +description: |
> +  The Atmel (now Microchip) SoCs have timers named Timer Counter Block. Each
> +  timer has three channels with two counters each.
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - atmel,at91rm9200-tcb
> +          - atmel,at91sam9x5-tcb
> +      - const: simple-mfd
> +      - const: syscon
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    description:
> +      List of interrupts. One interrupt per TCB channel if available or one
> +      interrupt for the TC block
> +    minItems: 1
> +    maxItems: 3
> +
> +  clock-names:
> +    description:
> +      List of clock names. Always includes t0_clk and slow clk. Also includes
> +      t1_clk and t2_clk if a clock per channel is available.

This description can be expressed as:

allOf:
  - contains: 
      const: t0_clk
  - contains: 
      const: slow_clk

However, if there's only 2 combinations to support with either 2 clocks 
or 4 clocks, then a 'oneOf' listing the 2 exact items lists would be 
better.

> +    minItems: 2
> +    maxItems: 4
> +    items:
> +      enum:
> +        - t0_clk
> +        - t1_clk
> +        - t2_clk
> +        - slow_clk
> +
> +  clocks:
> +    minItems: 2
> +    maxItems: 4
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +  - '#address-cells'
> +  - '#size-cells'

additionalProperties: false

> +
> +examples:
> +  - |
> +    /* One interrupt per TC block: */
> +        tcb0: timer@fff7c000 {
> +                compatible = "atmel,at91rm9200-tcb", "simple-mfd", "syscon";

A simple-mfd without child nodes?

> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                reg = <0xfff7c000 0x100>;
> +                interrupts = <18 4>;
> +                clocks = <&tcb0_clk>, <&clk32k>;
> +                clock-names = "t0_clk", "slow_clk";
> +        };
> +
> +    /* One interrupt per TC channel in a TC block: */
> +        tcb1: timer@fffdc000 {
> +                compatible = "atmel,at91rm9200-tcb", "simple-mfd", "syscon";
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                reg = <0xfffdc000 0x100>;
> +                interrupts = <26 4>, <27 4>, <28 4>;
> +                clocks = <&tcb1_clk>, <&clk32k>;
> +                clock-names = "t0_clk", "slow_clk";
> +        };
> diff --git a/Documentation/devicetree/bindings/timer/atmel,tcb-timer.yaml b/Documentation/devicetree/bindings/timer/atmel,tcb-timer.yaml
> new file mode 100644
> index 000000000000..a6173ceab6be
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/timer/atmel,tcb-timer.yaml
> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/timer/atmel,tcb-timer.yaml#";
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#";
> +
> +title: Atmel Timer Counter Block timer channel
> +
> +maintainers:
> +  - Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> +
> +description: |
> +  The Atmel (now Microchip) Timer Counter Block have multiple channels that can
> +  be used as timers.
> +
> +properties:
> +  compatible:
> +    const: atmel,tcb-timer
> +  reg:
> +    description:
> +      List of channels to use for this particular timer.
> +    minItems: 1
> +    maxItems: 3
> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false

This should just be merged into the 1st schema with this being 
defined as child nodes.

> +
> +examples:
> +  - |
> +        timer@fff7c000 {
> +                compatible = "atmel,at91rm9200-tcb", "simple-mfd", "syscon";
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                reg = <0xfff7c000 0x100>;
> +                interrupts = <18 4>;
> +                clocks = <&tcb0_clk>, <&clk32k>;
> +                clock-names = "t0_clk", "slow_clk";
> +
> +                timer@0 {
> +                        compatible = "atmel,tcb-timer";
> +                        reg = <0>, <1>;
> +                };
> +
> +                timer@2 {
> +                        compatible = "atmel,tcb-timer";
> +                        reg = <2>;
> +                };
> +        };
> -- 
> 2.25.2
>