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Message-ID: <1a8c006d-c9b9-9fd0-147e-7e511cb236fe@linaro.org>
Date:   Wed, 18 Jan 2023 14:40:00 +0100
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Subject: Re: [PATCH v6 1/2] dt-bindings: leds: backlight: Add Kinetic KTZ8866
 backlight
Content-Language: en-US
To:     Jianhua Lu <lujianhua000@gmail.com>, Lee Jones <lee@kernel.org>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        Jingoo Han <jingoohan1@gmail.com>, Pavel Machek <pavel@ucw.cz>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Helge Deller <deller@gmx.de>
Cc:     linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        linux-leds@vger.kernel.org, devicetree@vger.kernel.org,
        linux-fbdev@vger.kernel.org
References: <20230118131002.15453-1-lujianhua000@gmail.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20230118131002.15453-1-lujianhua000@gmail.com>
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Precedence: bulk

On 18/01/2023 14:10, Jianhua Lu wrote:
> Add Kinetic KTZ8866 backlight binding documentation.
> 
> Signed-off-by: Jianhua Lu <lujianhua000@gmail.com>
> ---
> Changes in v2:
>   - Remove "items" between "compatible" and "const: kinetic,ktz8866"
>   - Change "additionalProperties" to "unevaluatedProperties"
> 
> Changes in v3:
>   - Add Krzysztof's R-b
> 
> Changes in v4:
>   - Drop Krzysztof's R-b
>   - Add some new properties
> 
> Changes in v5:
>   - Add missing enum under property description.
>   - Rename uncorrect properties.
> 
> Changes in v6:
>   - Correct wrong property suffix and description.
> 
>  .../leds/backlight/kinetic,ktz8866.yaml       | 59 +++++++++++++++++++
>  1 file changed, 59 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> 
> diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> new file mode 100644
> index 000000000000..ca0deba14523
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktz8866.yaml
> @@ -0,0 +1,59 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/backlight/kinetic,ktz8866.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Kinetic Technologies KTZ8866 backlight
> +
> +maintainers:
> +  - Jianhua Lu <lujianhua000@gmail.com>
> +
> +description: |
> +  The Kinetic Technologies KTZ8866 is a high efficiency 6-sinks led backlight
> +  with dual lcd bias power.
> +  https://www.kinet-ic.com/ktz8866/
> +
> +allOf:
> +  - $ref: common.yaml#
> +
> +properties:
> +  compatible:
> +    const: kinetic,ktz8866
> +
> +  current-num-sinks:
> +    description: Number of LED current sinks.
> +    enum: [1, 2, 3, 4, 5, 6]
> +
> +  current-ramping-time-ms:
> +    description: LED current ramping time in milliseconds.
> +    enum: [2, 4, 8, 16, 32, 64, 128, 192, 256, 320, 384, 448, 512, 576, 640]
> +
> +  led-ramping-time-ms:
> +    description: |
> +      LED on/off ramping time in milliseconds, note that the case 0 will be mapped
> +      to 512μs because ktz8866 can't ramp faster than it.

Aren't you just missing supplies here and their ramp up time?

> +    enum: [0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384]
> +
> +  enable-lcd-bias:
> +    description: Set if we want to output bias power supply for LCD.

Is it a generic property? I don't see any other users, so this looks
device specific thus needs vendor prefix.

This applies to all of the properties. They might be generic or might
not, I don't know the backlight hardware that much.

> +    type: boolean
> +
> +required:
> +  - compatible
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    backlight {
> +        compatible = "kinetic,ktz8866";
> +
> +        pinctrl-names = "default";
> +        pinctrl-0 = <&bl_en_default>;
> +
> +        current-num-sinks = <5>;
> +        current-ramping-time-ms = <128>;
> +        led-ramping-time-ms = <1>;
> +        enable-lcd-bias;
> +    };

Best regards,
Krzysztof