Re: [PATCH] arm64: dts: rockchip: fix input enable pinconf on rk3399

[Caleb Connolly]

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@xxxxxxxxxxxxx>

Reviewed-by: Caleb Connolly <kc@xxxxxxxxxxxxxxxx>

> ---
>   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)