Re: [PATCH v2 1/4] arm64: dts: ti: k3-am64: Enable IO expander interrupt

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Dropping the internal pull-up on the PCA9538 IO expander interrupt pin on the SK board may leave the interrupt line floating.
--

--- Patch [1]: [PATCH v2 1/4] arm64: dts: ti: k3-am64: Enable IO expander interrupt ---
commit 9cfc964128ea9c7e025ee14807e51340a913a87a
Author: Judith Mendez <jm@ti.com>

arm64: dts: ti: k3-am64: Enable IO expander interrupt

This commit configures the MMC1_SDWP pin to function as the interrupt line for
the IO expander on the AM64 EVM and SK boards. It moves the pin out of the
MMC1 pinmux node and assigns it to the expander node, setting it up as an
edge-falling interrupt.

> diff --git a/arch/arm64/boot/dts/ti/k3-am642-sk.dts b/arch/arm64/boot/dts/ti/k3-am642-sk.dts
> index d28a38c87f32a..aa87845d77598 100644
> --- a/arch/arm64/boot/dts/ti/k3-am642-sk.dts
> +++ b/arch/arm64/boot/dts/ti/k3-am642-sk.dts
> @@ -198,7 +199,6 @@ &main_pmx0 {
>  	main_mmc1_pins_default: main-mmc1-default-pins {
>  		bootph-all;
>  		pinctrl-single,pins = <
> -			AM64X_IOPAD(0x029c, PIN_INPUT_PULLUP, 0) /* (C20) MMC1_SDWP */
>  			AM64X_IOPAD(0x0298, PIN_INPUT_PULLUP, 0) /* (D19) MMC1_SDCD */
>  			AM64X_IOPAD(0x0294, PIN_INPUT_PULLUP, 0) /* (J19) MMC1_CMD */
>  			AM64X_IOPAD(0x0290, PIN_INPUT, 0) /* (#N/A) MMC1_CLKLB */

[ ... ]

> @@ -210,6 +210,13 @@ AM64X_IOPAD(0x027c, PIN_INPUT_PULLUP, 0) /* (K18) MMC1_DAT3 */
>  		>;
>  	};
>  
> +	main_gpio1_ioexp_intr_pins_default: main-gpio1-ioexp-intr-default-pins {
> +		pinctrl-single,pins = <
> +			AM64X_IOPAD(0x029c, PIN_INPUT, 7) /* (C20) MMC1_SDWP.GPIO1_78 */

[Severity: Medium]
Does the AM64 SK board have an external pull-up for this IO expander interrupt
line?

The original MMC1 configuration for this pin on the SK board used
PIN_INPUT_PULLUP. Since the PCA9538 interrupt output is typically open-drain,
configuring it as PIN_INPUT here drops the internal pull-up. If there is no
external pull-up on the board, could this leave the line floating and trigger
spurious edge-falling interrupt storms?

> +		>;
> +		bootph-all;
> +	};

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260805004821.416613-1-jm@ti.com?part=1