Re: [PATCH] dt-bindings: i2c: conversion of i2c-st into DT schema YAML

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 10/02/2023 11:12, Alain Volmat wrote:
> File st,i2c.yaml replaces i2c-st.txt for the i2c-st driver.

Subject: dt-bindings: i2c: st,sti-i2c: convert to DT schema
(same reasoning as for SPI patch and maybe others)

> 
> Signed-off-by: Alain Volmat <avolmat@me.com>
> ---
>  .../devicetree/bindings/i2c/i2c-st.txt        | 41 -----------
>  .../devicetree/bindings/i2c/st,sti-i2c.yaml   | 72 +++++++++++++++++++
>  MAINTAINERS                                   |  2 +-
>  3 files changed, 73 insertions(+), 42 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-st.txt
>  create mode 100644 Documentation/devicetree/bindings/i2c/st,sti-i2c.yaml
> 
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-st.txt b/Documentation/devicetree/bindings/i2c/i2c-st.txt
> deleted file mode 100644
> index 4c26fda3844a..000000000000
> --- a/Documentation/devicetree/bindings/i2c/i2c-st.txt
> +++ /dev/null
> @@ -1,41 +0,0 @@
> -ST SSC binding, for I2C mode operation
> -
> -Required properties :
> -- compatible : Must be "st,comms-ssc-i2c" or "st,comms-ssc4-i2c"
> -- reg : Offset and length of the register set for the device
> -- interrupts : the interrupt specifier
> -- clock-names: Must contain "ssc".
> -- clocks: Must contain an entry for each name in clock-names. See the common
> -  clock bindings.
> -- A pinctrl state named "default" must be defined to set pins in mode of
> -  operation for I2C transfer.
> -
> -Optional properties :
> -- clock-frequency : Desired I2C bus clock frequency in Hz. If not specified,
> -  the default 100 kHz frequency will be used. As only Normal and Fast modes
> -  are supported, possible values are 100000 and 400000.
> -- st,i2c-min-scl-pulse-width-us : The minimum valid SCL pulse width that is
> -  allowed through the deglitch circuit. In units of us.
> -- st,i2c-min-sda-pulse-width-us : The minimum valid SDA pulse width that is
> -  allowed through the deglitch circuit. In units of us.
> -- A pinctrl state named "idle" could be defined to set pins in idle state
> -  when I2C instance is not performing a transfer.
> -- A pinctrl state named "sleep" could be defined to set pins in sleep state
> -  when driver enters in suspend.
> -
> -
> -
> -Example :
> -
> -i2c0: i2c@fed40000 {
> -	compatible	= "st,comms-ssc4-i2c";
> -	reg		= <0xfed40000 0x110>;
> -	interrupts	=  <GIC_SPI 187 IRQ_TYPE_LEVEL_HIGH>;
> -	clocks		= <&clk_s_a0_ls CLK_ICN_REG>;
> -	clock-names	= "ssc";
> -	clock-frequency = <400000>;
> -	pinctrl-names	= "default";
> -	pinctrl-0	= <&pinctrl_i2c0_default>;
> -	st,i2c-min-scl-pulse-width-us = <0>;
> -	st,i2c-min-sda-pulse-width-us = <5>;
> -};
> diff --git a/Documentation/devicetree/bindings/i2c/st,sti-i2c.yaml b/Documentation/devicetree/bindings/i2c/st,sti-i2c.yaml
> new file mode 100644
> index 000000000000..dd6ff18b9ed7
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/st,sti-i2c.yaml
> @@ -0,0 +1,72 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/i2c/st,sti-i2c.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: I2C controller embedded in STMicroelectronics STi platform
> +
> +maintainers:
> +  - Patrice Chotard <patrice.chotard@foss.st.com>
> +
> +allOf:
> +  - $ref: /schemas/i2c/i2c-controller.yaml#
> +
> +properties:
> +  compatible:
> +    enum:
> +      - st,comms-ssc-i2c
> +      - st,comms-ssc4-i2c
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  clock-names:
> +    maxItems: 1
> +
> +  clock-frequency:
> +    enum: [ 100000, 400000 ]

default: 100000

> +
> +  st,i2c-min-scl-pulse-width-us:
> +    description:
> +      The minimum valid SCL pulse width that is allowed through the
> +      deglitch circuit. In units of us.
> +    maxItems: 1

maxItems should not be needed.

> +
> +  st,i2c-min-sda-pulse-width-us:
> +    description:
> +      The minimum valid SDA pulse width that is allowed through the
> +      deglitch circuit. In units of us.
> +    maxItems: 1

Ditto

> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/clock/stih407-clks.h>
> +    i2c@fed40000 {
> +        compatible	= "st,comms-ssc4-i2c";

Drop unnecessary spaces before =


Best regards,
Krzysztof