Re: [PATCH v6 3/5] arm64: dts: renesas: add support for solidrun rzg2l som and hb-iiot evb

[Josua Mayer <josua@solid-run.com>]

On 10/08/2026 10:26, sashiko-bot@kernel.org wrote:
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [Medium] Lost interrupts for child devices due to edge-triggered parent interrupt configuration on the I2C expander
> --
>
> --- Patch [3]: [PATCH v6 3/5] arm64: dts: renesas: add support for solidrun rzg2l som and hb-iiot evb ---
> commit 3f1957626f1e1e5ab1e7ddedbfb53c5dea3788e0
> Author: Josua Mayer <josua@solid-run.com>
>
> arm64: dts: renesas: add support for solidrun rzg2l som and hb-iiot evb
>
> This commit adds device tree support for the SolidRun RZ/G2L SoM on the
> Hummingboard IIoT carrier board, including Ethernet, eMMC, USB, and
> configurable mux states for various interfaces.
>
> Link: https://www.solid-run.com/embedded-industrial-iot/renesas-rz-family/rz-g2l-som/
> Link: https://www.solid-run.com/embedded-industrial-iot/renesas-rz-family/hummingboard-rz-series-sbcs/hummingboard-rz-g2l-iot-sbc/
>
>> diff --git a/arch/arm64/boot/dts/renesas/rzg2l-hummingboard-iiot-common.dtsi b/arch/arm64/boot/dts/renesas/rzg2l-hummingboard-iiot-common.dtsi
>> new file mode 100644
>> index 0000000000000..eaec4cca76949
>> --- /dev/null
>> +++ b/arch/arm64/boot/dts/renesas/rzg2l-hummingboard-iiot-common.dtsi
> [ ... ]
>
>> +	tca6416_u21: gpio@21 {
>> +		compatible = "ti,tcal6416";
>> +		reg = <0x21>;
> [ ... ]
>
>> +		/* Level triggered irq does not currently work well on RZ/G2L, fall-back to edge */
>> +		interrupts-extended = <&pinctrl RZG2L_GPIO(4, 0) IRQ_TYPE_EDGE_FALLING>;
> [ ... ]
>
>> +	light-sensor@44 {
>> +		compatible = "isil,isl29023";
>> +		reg = <0x44>;
>> +		/* IRQ shared between accelerometer, light-sensor and Tamper input (J5007) */
>> +		interrupts-extended = <&tca6416_u21 7 IRQ_TYPE_LEVEL_LOW>;
>> +	};
>> +
>> +	accelerometer@53 {
>> +		compatible = "adi,adxl345";
>> +		reg = <0x53>;
>> +		interrupts-extended = <&tca6416_u21 7 IRQ_TYPE_LEVEL_LOW>;
>> +		/* IRQ shared between accelerometer, light-sensor and Tamper input (J5007) */
>> +		interrupt-names = "INT1";
>> +	};
> [Severity: Medium]
> Will this edge-triggered configuration cause lost interrupts for the child
> devices sharing this expander?
>
> The parent expander (tca6416_u21) interrupt is forced to
> IRQ_TYPE_EDGE_FALLING. However, child devices like the accelerometer and
> light sensor are configured to use IRQ_TYPE_LEVEL_LOW on the shared pin 7.
>
> If one device asserts its interrupt (pulling the shared line low), the
> expander will trigger a falling edge to the SoC. If the second device
> also asserts its interrupt before the first is cleared, the shared line
> remains low even after the first device deasserts it.
>
> Because the SoC parent interrupt is strictly edge-triggered, no second
> falling edge is generated in this scenario. Could this leave the interrupt
> line stuck low permanently and drop all future interrupts from these sensors?
>
It might, it might not, for now this is the compromise.
Maybe one day rzg2l pinctrl/gpio driver will implement level-triggered irq.

I consider this not blocking.