Re: [PATCH v2] iio: adc: bcm_iproc_adc: Convert probe() to use dev_err_probe()

[Andy Shevchenko]

On Thu, Jul 30, 2026 at 07:32:45PM +0530, mdshahid03@xxxxxxxxx wrote:

> Replace open-coded probe error handling with dev_err_probe() for
> resource acquisition and initialization failures.
> 
> This simplifies the error paths, avoids repetitive error handling,
> and automatically suppresses duplicate messages when -EPROBE_DEFER is
> returned while preserving the existing error messages.
> 
> Also remove the redundant error message after iproc_adc_enable(),
> allowing the error to be propagated without additional logging.

...

> static int iproc_adc_probe(struct platform_device *pdev)

While at it, consider adding

	struct device *dev = &pdev->dev;

at the top of the function to simplify the below calls.

>  	adc_priv->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
>  			   "adc-syscon");
> -	if (IS_ERR(adc_priv->regmap)) {
> -		dev_err(&pdev->dev, "failed to get handle for tsc syscon\n");
> -		ret = PTR_ERR(adc_priv->regmap);
> -		return ret;
> -	}
> +	if (IS_ERR(adc_priv->regmap))
> +		return dev_err_probe(&pdev->dev,
> +				     PTR_ERR(adc_priv->regmap),
> +				     "failed to get handle for tsc syscon\n");

		return dev_err_probe(dev, PTR_ERR(adc_priv->regmap),
				     "failed to get handle for tsc syscon\n");

>  	adc_priv->adc_clk = devm_clk_get(&pdev->dev, "tsc_clk");
> -	if (IS_ERR(adc_priv->adc_clk)) {
> -		dev_err(&pdev->dev,
> -			"failed getting clock tsc_clk\n");
> -		ret = PTR_ERR(adc_priv->adc_clk);
> -		return ret;
> -	}
> +	if (IS_ERR(adc_priv->adc_clk))
> +		return dev_err_probe(&pdev->dev,
> +				     PTR_ERR(adc_priv->adc_clk),
> +				     "failed getting clock tsc_clk\n");

And here, and so on...

...

>  	adc_priv->irqno = platform_get_irq(pdev, 0);
>  	if (adc_priv->irqno < 0)
> -		return adc_priv->irqno;
> +		return dev_err_probe(&pdev->dev,
> +				     adc_priv->irqno,
> +				     "failed to get IRQ\n");

This is wrong. The above call print an error.

>  	ret = regmap_clear_bits(adc_priv->regmap, IPROC_REGCTL2,
>  				IPROC_ADC_AUXIN_SCAN_ENA);
> -	if (ret) {
> -		dev_err(&pdev->dev, "failed to write IPROC_REGCTL2 %d\n", ret);
> -		return ret;
> -	}
> +	if (ret)
> +		return dev_err_probe(&pdev->dev,
> +				     ret,
> +				     "failed to write IPROC_REGCTL2\n");

It's a one line still (with the above change):

		return dev_err_probe(dev, ret, "failed to write IPROC_REGCTL2\n");

>  	ret = devm_request_threaded_irq(&pdev->dev, adc_priv->irqno,
>  				iproc_adc_interrupt_handler,
>  				iproc_adc_interrupt_thread,
>  				IRQF_SHARED, "iproc-adc", indio_dev);
> -	if (ret) {
> -		dev_err(&pdev->dev, "request_irq error %d\n", ret);
> -		return ret;
> -	}

> +	if (ret)
> +		return dev_err_probe(&pdev->dev,
> +				     ret,
> +				     "failed to request IRQ\n");

This should be a separate patch to drop the dup message. The IRQ core prints
it.

...

> +		return dev_err_probe(&pdev->dev,
> +				     ret,
> +				     "failed to enable clock\n");

One line.

-- 
With Best Regards,
Andy Shevchenko