Re: [PATCH v2 4/9] ARM: tegra: lg-x3: Add light sensor node

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] arm: dt: incorrect interrupt trigger polarity for APDS9900 sensor
--

commit 9cb1ebe47a901b15c3fac941849ede08f1799d2f
Author: Svyatoslav Ryhel <clamor95@gmail.com>

ARM: tegra: lg-x3: Add light sensor node

This commit adds the device tree node for the Avago APDS9900 ambient
light and proximity sensor to the tegra30-lg-x3 dtsi file.

> diff --git a/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi b/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi
> index d5365253c740b..4cd2bbc94f9d7 100644
> --- a/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi
> +++ b/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi
[ ... ]
> @@ -1106,6 +1106,19 @@ nfc@28 {
>  			firmware-gpios = <&gpio TEGRA_GPIO(R, 0) GPIO_ACTIVE_HIGH>;
>  		};
>  
> +		light-sensor@39 {
> +			compatible = "avago,apds9900";
> +			reg = <0x39>;
> +
> +			interrupt-parent = <&gpio>;
> +			interrupts = <TEGRA_GPIO(K, 2) IRQ_TYPE_EDGE_RISING>;

[Severity: Low]
Is IRQ_TYPE_EDGE_RISING the correct interrupt polarity for this sensor?

The device tree describes the APDS9900 interrupt as IRQ_TYPE_EDGE_RISING, but
the APDS9900 has an active-low open-drain interrupt pin, meaning it asserts
via a falling edge or low level. This appears to be a mismatch between the DT
hardware description and physical hardware.

While the Linux tsl2772 driver currently hardcodes IRQF_TRIGGER_FALLING
(masking the issue in Linux), could this latent hardware description bug break
interrupt handling for any OS or future driver refactoring that relies on the
DT-provided flags? Booting an OS that relies on the DT interrupt trigger flags
will configure the GPIO interrupt for a rising edge, which will fail to
trigger when the sensor pulls the line low.

> +
> +			vdd-supply = <&vdd_3v0_proxi>;
> +			vddio-supply = <&vdd_1v8_sen>;
> +
> +			led-max-microamp = <100000>;
> +		};
> +

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261004154456.145362-1-clamor95@gmail.com?part=4