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Message-ID: <5398cbe0-c681-5dd7-0b3e-3a586cc4915f@linaro.org>
Date:   Wed, 5 Apr 2023 13:51:02 +0200
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Subject: Re: [PATCH 1/2] dt-bindings: phy: imx8mq-usb: add phy tuning
 properties
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To:     Johannes Zink <j.zink@pengutronix.de>, vkoul@kernel.org,
        kishon@kernel.org, shawnguo@kernel.org, s.hauer@pengutronix.de,
        kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        jun.li@nxp.com, haibo.chen@nxp.com, linux-phy@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org
References: <20230405112118.1256151-1-j.zink@pengutronix.de>
 <20230405112118.1256151-2-j.zink@pengutronix.de>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20230405112118.1256151-2-j.zink@pengutronix.de>
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On 05/04/2023 13:21, Johannes Zink wrote:
> Add optional properties for tuning of usb phy.
> 
> Signed-off-by: Johannes Zink <j.zink@pengutronix.de>
> ---
>  .../bindings/phy/fsl,imx8mq-usb-phy.yaml      | 40 +++++++++++++++++++
>  1 file changed, 40 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml b/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml
> index e6f9f5540cc3..f452a41b4f32 100644
> --- a/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml
> +++ b/Documentation/devicetree/bindings/phy/fsl,imx8mq-usb-phy.yaml
> @@ -35,6 +35,46 @@ properties:
>      description:
>        A phandle to the regulator for USB VBUS.
>  
> +  fsl,phy-tx-vref-tune:
> +    description:
> +      HS DC Voltage level adjustment

"Level" in what units?

> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]
> +
> +  fsl,phy-tx-rise-tune:
> +    description:
> +      HS Transmitter Rise/Fall Time Adjustment
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [0, 1, 2, 3]
> +
> +  fsl,phy-tx-preemp-amp-tune:
> +    description:
> +      HS Transmitter Pre-Emphasis Current Control

If this is current then use standard unit suffixes.

> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [0, 1, 2, 3]
> +
> +  fsl,phy-tx-vboost-level:
> +    description:
> +      TX Voltage Boost Level
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [0, 2, 3]
> +
> +  fsl,phy-comp-dis-tune:
> +    description:
> +      Disconnect Threshold Adjustment
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [0, 1, 2, 3, 4, 5, 6, 7]
> +
> +  fsl,phy-pcs-tx-deemph-3p5db:
> +    description:
> +      TX De-Emphasis at 3.5 dB
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  fsl,phy-pcs-tx-swing-full:
> +    description:
> +      TX Amplitude

I have feeling you just pasted here short titles from datasheet. They
are not that helpful.


Best regards,
Krzysztof