Re: [PATCH v2 3/3] dt-bindings: gpio: Add Nuvoton NPCM750 serial I/O expansion interface(SGPIO)

[Krzysztof Kozlowski]

On 08/11/2022 10:28, Jim Liu wrote:
> NPCM750 include two SGPIO modules.
> Each module supports up to 64 input and 64 output pins.
> the output pin must be serial to parallel device(such as the hc595)
> the input in must be parallel to serial device(such as the hc165)
> 
> Signed-off-by: Jim Liu <JJLIU0@xxxxxxxxxxx>
> ---
> Changes for v2:
>    - modify description
> ---
>  .../bindings/gpio/nuvoton,sgpio.yaml          | 79 +++++++++++++++++++
>  1 file changed, 79 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/gpio/nuvoton,sgpio.yaml
> 
> diff --git a/Documentation/devicetree/bindings/gpio/nuvoton,sgpio.yaml b/Documentation/devicetree/bindings/gpio/nuvoton,sgpio.yaml
> new file mode 100644
> index 000000000000..331e3cb28b98
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/nuvoton,sgpio.yaml
> @@ -0,0 +1,79 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/gpio/nuvoton,sgpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Nuvoton SGPIO controller
> +
> +maintainers:
> +  - Jim LIU <JJLIU0@xxxxxxxxxxx>
> +
> +description:

description: |

> +  This SGPIO controller is for NUVOTON NPCM7xx and NPCM8xx SoC,
> +  NPCM7xx/NPCM8xx have two sgpio module each module can support up
> +  to 64 output pins,and up to 64 input pin.
> +  Nuvoton NPCM750 SGPIO module is base on serial to parallel IC (HC595)
> +  and parallel to serial IC (HC165).
> +  GPIO pins can be programmed to support the following options
> +  - Support interrupt option for each input port and various interrupt
> +    sensitivity option (level-high, level-low, edge-high, edge-low)
> +  - Directly connected to APB bus and its shift clock is from APB bus clock
> +    divided by a programmable value.
> +  - nin_gpios is number of input GPIO lines
> +  - nout_gpios is number of output GPIO lines
> +  - ngpios is number of nin_gpios GPIO lines and nout_gpios GPIO lines.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - nuvoton,npcm750-sgpio
> +      - nuvoton,npcm845-sgpio
> +
> +  reg:
> +    maxItems: 1
> +
> +  gpio-controller: true
> +
> +  '#gpio-cells':
> +    const: 2
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  nin_gpios: true
> +
> +  nout_gpios: true

These have several issues. No underscores, missing type, no description,
missing maxItems (if these were GPIOs...)

> +
> +  bus-frequency: true

Why? Bus frequency of what? This is a property of bus controllers. You
need to explain in details in description what is this about.

> +
> +required:
> +  - compatible
> +  - reg
> +  - gpio-controller
> +  - '#gpio-cells'
> +  - interrupts
> +  - nin_gpios
> +  - nout_gpios
> +  - clocks
> +  - bus-frequency
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/nuvoton,npcm7xx-clock.h>
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    sgpio1: sgpio@101000 {
> +        compatible = "nuvoton,npcm750-sgpio";
> +        reg = <0x101000 0x200>;
> +        clocks = <&clk NPCM7XX_CLK_APB3>;
> +        interrupts = <GIC_SPI 19 IRQ_TYPE_LEVEL_HIGH>;
> +        bus-frequency = <16000000>;
> +        gpio-controller;
> +        #gpio-cells = <2>;
> +        nin_gpios = <64>;
> +        nout_gpios = <64>;
> +        status = "disabled";

Drop


Best regards,
Krzysztof