Re: [PATCH v1] iio: adc: Use devm_iio_device_register() and dev_err_probe()

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Tue, 24 Jun 2025 23:33:51 -0300
"César Bispo" <dm.cesaraugusto@gmail.com> wrote:

> Replace iio_device_register() with devm_iio_device_register() to let the
> core handle cleanup automatically. This simplifies the driver and avoids
> manual error paths.
> 
> Also use dev_err_probe() for improved error handling and cleaner logs
> when deferrals happen.
> 
Hi. Always include the driver name in the patch title so that people
can quickly see if they care about it not!

iio: adc: qcom-pm8xxx-xoadc: USe devm_iio_device_register() and dev_err_probe()

> Signed-off-by: Cesar Bispo <cesar.bispo@ime.usp.br>
> Co-developed-by: Gabriel Ferreira <gabrielfsouza.araujo@usp.br>
> Signed-off-by: Gabriel Ferreira <gabrielfsouza.araujo@usp.br>
> ---
>  drivers/iio/adc/qcom-pm8xxx-xoadc.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/iio/adc/qcom-pm8xxx-xoadc.c b/drivers/iio/adc/qcom-pm8xxx-xoadc.c
> index 31f88cf7f7f1..447a924eca6d 100644
> --- a/drivers/iio/adc/qcom-pm8xxx-xoadc.c
> +++ b/drivers/iio/adc/qcom-pm8xxx-xoadc.c
> @@ -934,20 +934,18 @@ static int pm8xxx_xoadc_probe(struct platform_device *pdev)
>  	indio_dev->channels = adc->iio_chans;
>  	indio_dev->num_channels = adc->nchans;
>  
> -	ret = iio_device_register(indio_dev);
> +	ret = devm_iio_device_register(dev, indio_dev);
Look at how devm works before considering any such changes.
This change creates a race where you have turned the
power off before removing the userspace interfaces which is a very bad idea.

>  	if (ret)
> -		goto out_disable_vref;
> +		return dev_err_probe(dev, ret, "Unable to register %s\n", indio_dev->name);
>  
>  	ret = pm8xxx_calibrate_device(adc);
>  	if (ret)
> -		goto out_unreg_device;
> +		return ret;
>  
>  	dev_info(dev, "%s XOADC driver enabled\n", variant->name);
>  
>  	return 0;
>  
> -out_unreg_device:
> -	iio_device_unregister(indio_dev);
>  out_disable_vref:
>  	regulator_disable(adc->vref);
>