Re: [PATCH 1/2] arm64: dts: ti: k3-am67a-beagley-ai: Add gpio ranges

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Adding `pinctrl-single,gpio-range` on K3 platforms causes dynamic GPIO requests to silently overwrite the entire pad configuration register, destroying previously applied board-specific settings like pull-ups and drive strengths.
--

--- Patch [1]: [PATCH 1/2] arm64: dts: ti: k3-am67a-beagley-ai: Add gpio ranges ---
commit c5d1a1cd5d0bb91d0c680ae90328952c44500103
Author: David Lechner (TI) <dlechner@baylibre.com>

arm64: dts: ti: k3-am67a-beagley-ai: Add gpio ranges

Add pinctrl-single,gpio-range properties to the BeagleY-AI .dts so that
GPIOs get the correct pin mux when requested.

> diff --git a/arch/arm64/boot/dts/ti/k3-am67a-beagley-ai.dts b/arch/arm64/boot/dts/ti/k3-am67a-beagley-ai.dts
> index 5255e04b9ac76..599d576f694f6 100644
> --- a/arch/arm64/boot/dts/ti/k3-am67a-beagley-ai.dts
> +++ b/arch/arm64/boot/dts/ti/k3-am67a-beagley-ai.dts
> @@ -149,6 +149,19 @@ led-1 {
>  };
>  
>  &main_pmx0 {
> +	pinctrl-single,gpio-range =
> +		<&main_pmx0_range 0 32 PIN_GPIO_RANGE_IOPAD>,
> +		<&main_pmx0_range 33 38 PIN_GPIO_RANGE_IOPAD>,

[Severity: High]
Does adding pinctrl-single,gpio-range here cause dynamic GPIO requests to
silently overwrite the entire pad configuration register?

On K3 platforms, the pinctrl-single,function-mask is typically <0xffffffff>,
meaning the pad electrical properties and mux mode share the same register.
When a GPIO in these ranges is requested via gpiod_get(), the gpiolib path
calls the pinctrl driver's pcs_request_gpio().

Since the function mask is 0xffffffff, pcs_request_gpio() will execute:

    data &= ~pcs->fmask;
    data |= frange->gpiofunc;

Could this completely erase any previously applied board-specific settings
like pull-ups or drive strengths from a device's pinctrl-0 property, and
replace them with PIN_GPIO_RANGE_IOPAD (which includes PULL_DISABLE)?

[ ... ]

> @@ -267,6 +280,15 @@ &main_uart0 {
>  };
>  
>  &mcu_pmx0 {
> +	pinctrl-single,gpio-range =
> +		<&mcu_pmx_range 0 21 PIN_GPIO_RANGE_IOPAD>,
> +		<&mcu_pmx_range 23 1 PIN_GPIO_RANGE_IOPAD>,

[Severity: High]
Will this have the same pad configuration overwrite issue for the MCU domain
GPIOs when requested?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260728-arm-dts-beagleyai-gpio-info-v1-0-783ec90d54da@baylibre.com?part=1