Re: [PATCH v5 1/3] i2c: tegra: Fix reset error handling with ACPI

[Andy Shevchenko]

On Wed, Jul 02, 2025 at 07:04:47PM +0530, Akhil R wrote:
> The acpi_evaluate_object() returns an ACPI error code and not the
> Linux one. For the some platforms the error will have positive code
> which may be interpreted incorrectly. Use ACPI_FAILURE() to determine
> the failure and return the error. Also move the reset to a separate
> function to handle this better.

...

> +static int tegra_i2c_reset(struct tegra_i2c_dev *i2c_dev)
> +{
> +	acpi_handle handle = ACPI_HANDLE(i2c_dev->dev);
> +	int err;
> +
> +	if (handle) {
> +		err = acpi_evaluate_object(handle, "_RST", NULL, NULL);
> +		if (ACPI_FAILURE(err))
> +			return -EIO;
> +
> +		return 0;
> +	}
> +
> +	return reset_control_reset(i2c_dev->rst);


It's better to be written other way around:

	acpi_handle handle;
	int err;

	handle = ACPI_HANDLE(i2c_dev->dev);
	if (!handle)
		return reset_control_reset(i2c_dev->rst);

	err = acpi_evaluate_object(handle, "_RST", NULL, NULL);
	if (ACPI_FAILURE(err))
		return -EIO;

	return 0;

> +}

Other than that, LGTM,

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

...

> +	err = tegra_i2c_reset(i2c_dev);
>  	WARN_ON_ONCE(err);

Suggestion to improve in a separate change in the future:

Add a comment explaining why we WARN() here. I.o.w. why this condition
is so critical that we need to WARN().

-- 
With Best Regards,
Andy Shevchenko