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Date:   Wed, 19 Apr 2023 14:15:17 -0500
From:   Jeff LaBundy <jeff@labundy.com>
To:     Luca Ceresoli <luca.ceresoli@bootlin.com>
Cc:     Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        devicetree@vger.kernel.org, Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Stephen Boyd <sboyd@kernel.org>,
        Jarrah Gosbell <kernel@undef.tools>,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Subject: Re: [PATCH] dt-bindings: input: touchscreen: goodix: clarify
 irq-gpios misleading text
Message-ID: <ZEA9xZH5+nEjDWcS@nixie71>
References: <20230419171849.946986-1-luca.ceresoli@bootlin.com>
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Hi Luca,

On Wed, Apr 19, 2023 at 07:18:49PM +0200, Luca Ceresoli wrote:
> The irq-gpios description misleading, apparently saying that driving the
> IRQ GPIO resets the device, which is even more puzzling as there is a reset
> GPIO as well.
> 
> In reality the IRQ pin can be driven during the reset sequence to configure
> the client address, as it becomes clear after checking both the datasheet
> and the driver code. Improve the text to clarify that.
> 
> Also rephrase to remove reference to the driver, which is not appropriate
> in the bindings.
> 
> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> ---
>  .../devicetree/bindings/input/touchscreen/goodix.yaml         | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml
> index 3d016b87c8df..26ad104052ba 100644
> --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml
> +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml
> @@ -37,8 +37,8 @@ properties:
>      maxItems: 1
>  
>    irq-gpios:
> -    description: GPIO pin used for IRQ. The driver uses the interrupt gpio pin
> -      as output to reset the device.
> +    description: GPIO pin used for IRQ. The IRQ line can be driven during the
> +      reset sequence to configure the client address.

This is a step in the right direction, but in my humble opinion it is now
ambiguous who drives the bidirectional IRQ pin (device or driver). Perhaps
combining both versions conveys the appropriate message:

"...The driver uses the interrupt GPIO pin as an output to configure the client
address during the reset sequence."

>      maxItems: 1
>  
>    reset-gpios:
> -- 
> 2.34.1
> 

Kind regards,
Jeff LaBundy