Re: [PATCH v4 2/3] backlight: rt4831: Adds DT binding document for Richtek RT4831 backlight

[Rob Herring <robh@kernel.org>]

On Sat, Dec 12, 2020 at 12:33:43AM +0800, cy_huang wrote:
> From: ChiYuan Huang <cy_huang@richtek.com>
> 
> Adds DT binding document for Richtek RT4831 backlight.
> 
> Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
> ---
> since v3
> - Move inlcude/dt-bindings/leds/rt4831-backlight.h from v3 mfd binding patch to here.
> - Add dual license tag in header and backlight binding document.
> - Left backlight dt-binding example only.
> ---
>  .../leds/backlight/richtek,rt4831-backlight.yaml   | 76 ++++++++++++++++++++++
>  include/dt-bindings/leds/rt4831-backlight.h        | 23 +++++++
>  2 files changed, 99 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml
>  create mode 100644 include/dt-bindings/leds/rt4831-backlight.h
> 
> diff --git a/Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml
> new file mode 100644
> index 00000000..f24c8d1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/richtek,rt4831-backlight.yaml
> @@ -0,0 +1,76 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/backlight/richtek,rt4831-backlight.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Richtek RT4831 Backlight
> +
> +maintainers:
> +  - ChiYuan Huang <cy_huang@richtek.com>
> +
> +description: |
> +  RT4831 is a mutifunctional device that can provide power to the LCD display
> +  and LCD backlight.
> +
> +  For the LCD backlight, it can provide four channel WLED driving capability.
> +  Each channel driving current is up to 30mA
> +
> +  Datasheet is available at
> +  https://www.richtek.com/assets/product_file/RT4831A/DS4831A-05.pdf
> +
> +properties:
> +  compatible:
> +    const: richtek,rt4831-backlight
> +
> +  default-brightness:
> +    description: |
> +      The default brightness that applied to the system on start-up.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    minimum: 0
> +    maximum: 2048
> +
> +  max-brightness:
> +    description: |
> +      The max brightness for the H/W limit
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    minimum: 0
> +    maximum: 2048
> +
> +  richtek,pwm-enable:
> +    description: |
> +      Specify the backlight dimming following by PWM duty or by SW control.
> +    type: boolean
> +
> +  richtek,bled-ovp-sel:
> +    description: |
> +      Backlight OVP level selection, currently support 17V/21V/25V/29V.
> +    $ref: /schemas/types.yaml#/definitions/uint8
> +    default: 1
> +    minimum: 0
> +    maximum: 3
> +
> +  richtek,channel-use:
> +    description: |
> +      Backlight LED channel to be used.
> +      BIT 0/1/2/3 is used to indicate led channel 1/2/3/4 enable or disable.
> +    $ref: /schemas/types.yaml#/definitions/uint8
> +    minimum: 1
> +    maximum: 15
> +
> +required:
> +  - compatible
> +  - richtek,channel-use
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/leds/rt4831-backlight.h>
> +    backlight {
> +      compatible = "richtek,rt4831-backlight";
> +      default-brightness = <1024>;
> +      max-brightness = <2048>;
> +      richtek,bled-ovp-sel = /bits/ 8 <RT4831_BLOVPLVL_21V>;
> +      richtek,channel-use = /bits/ 8 <RT4831_BLED_ALLCHEN>;

This is in the MFD schema already, so drop the example.

> +    };
> diff --git a/include/dt-bindings/leds/rt4831-backlight.h b/include/dt-bindings/leds/rt4831-backlight.h
> new file mode 100644
> index 00000000..125c635
> --- /dev/null
> +++ b/include/dt-bindings/leds/rt4831-backlight.h
> @@ -0,0 +1,23 @@
> +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> +/*
> + * This header provides constants for rt4831 backlight bindings.
> + *
> + * Copyright (C) 2020, Richtek Technology Corp.
> + * Author: ChiYuan Huang <cy_huang@richtek.com>
> + */
> +
> +#ifndef _DT_BINDINGS_RT4831_BACKLIGHT_H
> +#define _DT_BINDINGS_RT4831_BACKLIGHT_H
> +
> +#define RT4831_BLOVPLVL_17V	0
> +#define RT4831_BLOVPLVL_21V	1
> +#define RT4831_BLOVPLVL_25V	2
> +#define RT4831_BLOVPLVL_29V	3
> +
> +#define RT4831_BLED_CH1EN	(1 << 0)
> +#define RT4831_BLED_CH2EN	(1 << 1)
> +#define RT4831_BLED_CH3EN	(1 << 2)
> +#define RT4831_BLED_CH4EN	(1 << 3)
> +#define RT4831_BLED_ALLCHEN	((1 << 4) - 1)
> +
> +#endif /* _DT_BINDINGS_RT4831_BACKLIGHT_H */
> -- 
> 2.7.4
>