Re: [PATCH v1 2/9 RESEND] ARM: tegra: lg-x3: Set PMIC's RTC address

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The DT patch sets a non-standard RTC address (0x48) via a secondary `reg` property, but the rtc-max77686 driver ignores it and uses a hardcoded address (0x68). As a result, the commit fails to fix the RTC, leaving it non-functional.
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commit 034a90db28ba53add991c38ac94042a85b474aec
Author: Svyatoslav Ryhel <clamor95@gmail.com>

ARM: tegra: lg-x3: Set PMIC's RTC address

This commit updates the device tree for LG X3 devices by adding a secondary
I2C address for the max77663 PMIC's RTC module. The intention is to
override the default RTC address because it is located at a non-standard
address on this board.

> diff --git a/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi b/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi
> --- a/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi
> +++ b/arch/arm/boot/dts/nvidia/tegra30-lg-x3.dtsi
> @@ -1297,7 +1297,8 @@ pwr_i2c: i2c@7000d000 {
>  
>  		pmic: max77663@1c {
>  			compatible = "maxim,max77663";
> -			reg = <0x1c>;
> +			reg = <0x1c>, <0x48>;
> +			reg-names = "pmic", "rtc";

Does the rtc-max77686 driver actually parse this secondary reg property?

Looking at the driver, it appears to use a hardcoded address via
devm_i2c_new_dummy_device(..., info->drv_data->rtc_i2c_addr), where
rtc_i2c_addr is fixed to 0x68.

Without companion changes to the driver to read the reg property or use
i2c_new_ancillary_device(), it seems the driver will still attempt to access
the RTC at 0x68 and ignore the 0x48 address specified here.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260511074859.24930-1-clamor95@gmail.com?part=2