Re: [PATCH 2/3] dt-bindings: gpio: Conver Unisoc EIC controller binding to yaml

[Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>]

On 28/09/2022 11:29, Chunyan Zhang wrote:
> From: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
> 
> Convert the Unisoc EIC controller binding to DT schema format.
> 
> Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
> ---
>  .../bindings/gpio/gpio-eic-sprd.txt           |  97 ------------
>  .../bindings/gpio/sprd,gpio-eic.yaml          | 145 ++++++++++++++++++
>  2 files changed, 145 insertions(+), 97 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt
>  create mode 100644 Documentation/devicetree/bindings/gpio/sprd,gpio-eic.yaml
> 
> diff --git a/Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt b/Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt
> deleted file mode 100644
> index 54040a2bfe3a..000000000000
> --- a/Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt
> +++ /dev/null
> @@ -1,97 +0,0 @@
> -Spreadtrum EIC controller bindings
> -
> -The EIC is the abbreviation of external interrupt controller, which can
> -be used only in input mode. The Spreadtrum platform has 2 EIC controllers,
> -one is in digital chip, and another one is in PMIC. The digital chip EIC
> -controller contains 4 sub-modules: EIC-debounce, EIC-latch, EIC-async and
> -EIC-sync. But the PMIC EIC controller contains only one EIC-debounce sub-
> -module.
> -
> -The EIC-debounce sub-module provides up to 8 source input signal
> -connections. A debounce mechanism is used to capture the input signals'
> -stable status (millisecond resolution) and a single-trigger mechanism
> -is introduced into this sub-module to enhance the input event detection
> -reliability. In addition, this sub-module's clock can be shut off
> -automatically to reduce power dissipation. Moreover the debounce range
> -is from 1ms to 4s with a step size of 1ms. The input signal will be
> -ignored if it is asserted for less than 1 ms.
> -
> -The EIC-latch sub-module is used to latch some special power down signals
> -and generate interrupts, since the EIC-latch does not depend on the APB
> -clock to capture signals.
> -
> -The EIC-async sub-module uses a 32kHz clock to capture the short signals
> -(microsecond resolution) to generate interrupts by level or edge trigger.
> -
> -The EIC-sync is similar with GPIO's input function, which is a synchronized
> -signal input register. It can generate interrupts by level or edge trigger
> -when detecting input signals.
> -
> -Required properties:
> -- compatible: Should be one of the following:
> -  "sprd,sc9860-eic-debounce",
> -  "sprd,sc9860-eic-latch",
> -  "sprd,sc9860-eic-async",
> -  "sprd,sc9860-eic-sync",
> -  "sprd,sc2731-eic".
> -- reg: Define the base and range of the I/O address space containing
> -  the GPIO controller registers.
> -- gpio-controller: Marks the device node as a GPIO controller.
> -- #gpio-cells: Should be <2>. The first cell is the gpio number and
> -  the second cell is used to specify optional parameters.
> -- interrupt-controller: Marks the device node as an interrupt controller.
> -- #interrupt-cells: Should be <2>. Specifies the number of cells needed
> -  to encode interrupt source.
> -- interrupts: Should be the port interrupt shared by all the gpios.
> -
> -Example:
> -	eic_debounce: gpio@40210000 {
> -		compatible = "sprd,sc9860-eic-debounce";
> -		reg = <0 0x40210000 0 0x80>;
> -		gpio-controller;
> -		#gpio-cells = <2>;
> -		interrupt-controller;
> -		#interrupt-cells = <2>;
> -		interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
> -	};
> -
> -	eic_latch: gpio@40210080 {
> -		compatible = "sprd,sc9860-eic-latch";
> -		reg = <0 0x40210080 0 0x20>;
> -		gpio-controller;
> -		#gpio-cells = <2>;
> -		interrupt-controller;
> -		#interrupt-cells = <2>;
> -		interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
> -	};
> -
> -	eic_async: gpio@402100a0 {
> -		compatible = "sprd,sc9860-eic-async";
> -		reg = <0 0x402100a0 0 0x20>;
> -		gpio-controller;
> -		#gpio-cells = <2>;
> -		interrupt-controller;
> -		#interrupt-cells = <2>;
> -		interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
> -	};
> -
> -	eic_sync: gpio@402100c0 {
> -		compatible = "sprd,sc9860-eic-sync";
> -		reg = <0 0x402100c0 0 0x20>;
> -		gpio-controller;
> -		#gpio-cells = <2>;
> -		interrupt-controller;
> -		#interrupt-cells = <2>;
> -		interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
> -	};
> -
> -	pmic_eic: gpio@300 {
> -		compatible = "sprd,sc2731-eic";
> -		reg = <0x300>;
> -		interrupt-parent = <&sc2731_pmic>;
> -		interrupts = <5 IRQ_TYPE_LEVEL_HIGH>;
> -		gpio-controller;
> -		#gpio-cells = <2>;
> -		interrupt-controller;
> -		#interrupt-cells = <2>;
> -	};
> diff --git a/Documentation/devicetree/bindings/gpio/sprd,gpio-eic.yaml b/Documentation/devicetree/bindings/gpio/sprd,gpio-eic.yaml
> new file mode 100644
> index 000000000000..e25ee1884c07
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/sprd,gpio-eic.yaml
> @@ -0,0 +1,145 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright 2022 Unisoc Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/gpio/sprd,gpio-eic.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Unisoc EIC controller
> +
> +maintainers:
> +  - Orson Zhai <orsonzhai@xxxxxxxxx>
> +  - Baolin Wang <baolin.wang7@xxxxxxxxx>
> +  - Chunyan Zhang <zhang.lyra@xxxxxxxxx>
> +
> +description:
> +  The EIC is the abbreviation of external interrupt controller, which can
> +  be used only in input mode. The Spreadtrum platform has 2 EIC controllers,
> +  one is in digital chip, and another one is in PMIC. The digital chip EIC
> +  controller contains 4 sub-modules, i.e. EIC-debounce, EIC-latch, EIC-async and
> +  EIC-sync. But the PMIC EIC controller contains only one EIC-debounce sub-
> +  module.
> +
> +  The EIC-debounce sub-module provides up to 8 source input signal
> +  connections. A debounce mechanism is used to capture the input signals'
> +  stable status (millisecond resolution) and a single-trigger mechanism
> +  is introduced into this sub-module to enhance the input event detection
> +  reliability. In addition, this sub-module's clock can be shut off
> +  automatically to reduce power dissipation. Moreover the debounce range
> +  is from 1ms to 4s with a step size of 1ms. The input signal will be
> +  ignored if it is asserted for less than 1 ms.
> +
> +  The EIC-latch sub-module is used to latch some special power down signals
> +  and generate interrupts, since the EIC-latch does not depend on the APB
> +  clock to capture signals.
> +
> +  The EIC-async sub-module uses a 32kHz clock to capture the short signals
> +  (microsecond resolution) to generate interrupts by level or edge trigger.
> +
> +  The EIC-sync is similar with GPIO's input function, which is a synchronized
> +  signal input register. It can generate interrupts by level or edge trigger
> +  when detecting input signals.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - sprd,sc9860-eic-debounce
> +      - sprd,sc9860-eic-latch
> +      - sprd,sc9860-eic-async
> +      - sprd,sc9860-eic-sync
> +      - sprd,sc2731-eic
> +
> +  reg:
> +    minItems: 1
> +    maxItems: 4

Why up to 4 items? Previous bindings did not mention it. I also do not
see any users of this. Anyway you need to describe the items (items with
description) and restrict per variant in allOf:if:then


> +
> +  gpio-controller: true
> +
> +  "#gpio-cells":
> +    const: 2
> +
> +  interrupt-controller: true
> +
> +  "#interrupt-cells":
> +    const: 2
> +
> +  interrupts:
> +    maxItems: 1
> +    description: The interrupt shared by all GPIO lines for this controller.
> +
> +required:
> +  - compatible
> +  - reg
> +  - gpio-controller
> +  - "#gpio-cells"
> +  - interrupt-controller
> +  - "#interrupt-cells"
> +  - interrupts
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> +    soc {
> +        #address-cells = <2>;
> +        #size-cells = <2>;
> +
> +        eic_debounce: gpio@40210000 {
> +            compatible = "sprd,sc9860-eic-debounce";
> +            reg = <0 0x40210000 0 0x80>;
> +            gpio-controller;
> +            #gpio-cells = <2>;
> +            interrupt-controller;
> +            #interrupt-cells = <2>;
> +            interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;

One example is enough. All others are the same.


Best regards,
Krzysztof