Re: [PATCH 1/4] dt-bindings: backlight: lp855x: convert to YAML and modernize

[Rob Herring <robh@kernel.org>]

On Sat, Apr 29, 2023 at 12:45:31PM +0200, Artur Weber wrote:
> Notable changes:
> - ROM child nodes use dashes instead of underscores; the driver
>   reads all child nodes regardless of their names, so this doesn't
>   break ABI.
> - pwm-period argument is deprecated, as it effectively duplicates
>   the period value provided in pwms. The driver continues to accept
>   the property, so this should not break ABI.
> 
> Signed-off-by: Artur Weber <aweber.kernel@gmail.com>
> ---
>  .../leds/backlight/lp855x-backlight.yaml      | 148 ++++++++++++++++++
>  .../bindings/leds/backlight/lp855x.txt        |  72 ---------
>  2 files changed, 148 insertions(+), 72 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/leds/backlight/lp855x-backlight.yaml
>  delete mode 100644 Documentation/devicetree/bindings/leds/backlight/lp855x.txt
> 
> diff --git a/Documentation/devicetree/bindings/leds/backlight/lp855x-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/lp855x-backlight.yaml
> new file mode 100644
> index 000000000000..dfe8131d2a32
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/lp855x-backlight.yaml
> @@ -0,0 +1,148 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/backlight/lp855x-backlight.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Texas Instruments LP855X backlight controllers
> +
> +maintainers:
> +  - Artur Weber <aweber.kernel@gmail.com>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - ti,lp8550
> +      - ti,lp8551
> +      - ti,lp8552
> +      - ti,lp8553
> +      - ti,lp8555
> +      - ti,lp8556
> +      - ti,lp8557
> +
> +  reg:
> +    maxItems: 1
> +
> +  dev-ctrl:
> +    $ref: /schemas/types.yaml#/definitions/uint8
> +    description:
> +      Value of device control register. This is a device-specific value.
> +
> +  bl-name:
> +    $ref: /schemas/types.yaml#/definitions/string
> +    description: Backlight device name.
> +
> +  init-brt:
> +    $ref: /schemas/types.yaml#/definitions/uint8
> +    description: Initial value of backlight brightness.
> +
> +  power-supply:
> +    description: Regulator which controls the 3V rail.
> +
> +  enable-supply:
> +    description: Regulator which controls the EN/VDDIO input.
> +
> +  pwms:
> +    maxItems: 1
> +    description: |
> +      PWM channel to use for controlling the backlight; setting this
> +      enables the PWM-based backlight control mode.
> +
> +  pwm-names: true
> +
> +  pwm-period:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      PWM period value. Deprecated; set the period value in the pwms
> +      property instead.
> +    deprecated: true
> +
> +patternProperties:
> +  "^rom-[0-9a-f]{2}h$":
> +    type: object
> +    description: Nodes containing the values of configuration registers.

       additionalProperties: false

With that,

Reviewed-by: Rob Herring <robh@kernel.org>

> +    properties:
> +      rom-addr:
> +        $ref: /schemas/types.yaml#/definitions/uint8
> +        description: Register address of ROM area to be updated.
> +
> +      rom-val:
> +        $ref: /schemas/types.yaml#/definitions/uint8
> +        description: Value to write to the ROM register.
> +
> +required:
> +  - compatible
> +  - reg
> +  - dev-ctrl
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        backlight@2c {
> +            compatible = "ti,lp8555";
> +            reg = <0x2c>;
> +
> +            dev-ctrl = /bits/ 8 <0x00>;
> +
> +            pwms = <&pwm 0 10000>;
> +            pwm-names = "lp8555";
> +
> +            /* 4V OV, 4 output LED0 string enabled */
> +            rom-14h {
> +              rom-addr = /bits/ 8 <0x14>;
> +              rom-val = /bits/ 8 <0xcf>;
> +            };
> +
> +            /* Heavy smoothing, 24ms ramp time step */
> +            rom-15h {
> +              rom-addr = /bits/ 8 <0x15>;
> +              rom-val = /bits/ 8 <0xc7>;
> +            };
> +
> +            /* 4 output LED1 string enabled */
> +            rom-19h {
> +              rom-addr = /bits/ 8 <0x19>;
> +              rom-val = /bits/ 8 <0x0f>;
> +            };
> +        };
> +    };
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        backlight@2c {
> +            compatible = "ti,lp8556";
> +            reg = <0x2c>;
> +
> +            bl-name = "lcd-bl";
> +            dev-ctrl = /bits/ 8 <0x85>;
> +            init-brt = /bits/ 8 <0x10>;
> +        };
> +      };
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        backlight@2c {
> +            compatible = "ti,lp8557";
> +            reg = <0x2c>;
> +            enable-supply = <&backlight_vddio>;
> +            power-supply = <&backlight_vdd>;
> +
> +            dev-ctrl = /bits/ 8 <0x41>;
> +            init-brt = /bits/ 8 <0x0a>;
> +
> +            /* 4V OV, 4 output LED string enabled */
> +            rom-14h {
> +              rom-addr = /bits/ 8 <0x14>;
> +              rom-val = /bits/ 8 <0xcf>;
> +            };
> +        };
> +    };