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Message-ID: <a13bce60-25b4-d075-d56a-d1283e91e3ba@linaro.org>
Date:   Thu, 11 Aug 2022 12:14:48 +0300
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Subject: Re: [PATCH 1/2] dt-bindings: usb: Introduce GPIO-based SBU mux
Content-Language: en-US
To:     Bjorn Andersson <bjorn.andersson@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc:     linux-usb@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        Prashant Malani <pmalani@chromium.org>,
        Stephen Boyd <swboyd@chromium.org>,
        Pin-yen Lin <treapking@chromium.org>
References: <20220810204750.3672362-1-bjorn.andersson@linaro.org>
 <20220810204750.3672362-2-bjorn.andersson@linaro.org>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20220810204750.3672362-2-bjorn.andersson@linaro.org>
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Precedence: bulk

On 10/08/2022 23:47, Bjorn Andersson wrote:
> Introduce a binding for GPIO-based mux hardware used for connecting,
> disconnecting and switching orientation of the SBU lines in USB Type-C
> applications.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> ---
>  .../devicetree/bindings/usb/gpio-sbu-mux.yaml | 77 +++++++++++++++++++
>  1 file changed, 77 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/usb/gpio-sbu-mux.yaml
> 
> diff --git a/Documentation/devicetree/bindings/usb/gpio-sbu-mux.yaml b/Documentation/devicetree/bindings/usb/gpio-sbu-mux.yaml
> new file mode 100644
> index 000000000000..7d8aca40c7ca
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/usb/gpio-sbu-mux.yaml
> @@ -0,0 +1,77 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/usb/gpio-sbu-mux.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: GPIO-based SBU mux
> +
> +maintainers:
> +  - Bjorn Andersson <bjorn.andersson@linaro.org>
> +
> +description:
> +  In USB Type-C applications the SBU lines needs to be connected, disconnected
> +  and swapped depending on the altmode and orientation. This binding describes
> +  a family of hardware which perform this based on GPIO controls.

+Cc few folks.

This looks familiar to:

https://lore.kernel.org/linux-devicetree/eaf2fda8-0cd6-b518-10cb-4e21b5f8c909@linaro.org/T/#m39254b7f8970b3e1264f9d1a979557bb46ab162c

Rob and Stephen had several concerns about that approach.

Best regards,
Krzysztof