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Message-ID: <78769cf4-84cc-5195-57b8-823d9fc33794@postmarketos.org>
Date:   Thu, 15 Dec 2022 20:42:02 +0000
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Subject: Re: [PATCH] arm64: dts: rockchip: fix input enable pinconf on rk3399
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To:     Arnaud Ferraris <arnaud.ferraris@collabora.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Heiko Stuebner <heiko@sntech.de>, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     kernel@collabora.com
References: <20221215101947.254896-1-arnaud.ferraris@collabora.com>
From:   Caleb Connolly <kc@postmarketos.org>
In-Reply-To: <20221215101947.254896-1-arnaud.ferraris@collabora.com>
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Precedence: bulk


On 15/12/2022 10:19, Arnaud Ferraris wrote:
> When the input enable pinconf was introduced, a default drive-strength
> value of 2 was set for the pull up/down configs. However, this parameter
> is unneeded when configuring the pin as input, and having a single
> hardcoded value here is actually harmful: GPIOs on the RK3399 have
> various same drive-strength capabilities depending on the bank and port
> they belong to.
> 
> As an example, trying to configure the GPIO4_PD3 pin as an input with
> pull-up enabled fails with the following output:
> 
>    [   10.706542] rockchip-pinctrl pinctrl: unsupported driver strength 2
>    [   10.713661] rockchip-pinctrl pinctrl: pin_config_set op failed for pin 155
> 
> (acceptable drive-strength values for this pin being 3, 6, 9 and 12)
> 
> Let's drop the drive-strength property from all input pinconfs in order
> to solve this issue.
> 
> Fixes: ec48c3e82ca3 ("arm64: dts: rockchip: add an input enable pinconf to rk3399")
> Signed-off-by: Arnaud Ferraris <arnaud.ferraris@collabora.com>

Reviewed-by: Caleb Connolly <kc@postmarketos.org>

> ---
>   arch/arm64/boot/dts/rockchip/rk3399.dtsi | 2 --
>   1 file changed, 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> index 92c2207e686c..59858f2dc8b9 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> +++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
> @@ -2221,13 +2221,11 @@ pcfg_input_enable: pcfg-input-enable {
>   		pcfg_input_pull_up: pcfg-input-pull-up {
>   			input-enable;
>   			bias-pull-up;
> -			drive-strength = <2>;
>   		};
>   
>   		pcfg_input_pull_down: pcfg-input-pull-down {
>   			input-enable;
>   			bias-pull-down;
> -			drive-strength = <2>;
>   		};
>   
>   		clock {

-- 
Kind Regards,
Caleb (they/them)