Re: [PATCH v9 06/11] iio: adc: hx711: introduce hx711_chip_info structure

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] Driver probe unconditionally fails for legacy non-DT platform devices.
- [Low] Use of undeclared macro `__counted_by_ptr` causes a build failure.
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commit e7a943897aef3be5de1d3c4561e37e20e131b7c5
Author: Piyush Patle <piyushpatle228@gmail.com>

iio: adc: hx711: introduce hx711_chip_info structure

Add a per-variant static configuration structure and populate the IIO
device fields from it at probe time.

> diff --git a/drivers/iio/adc/hx711.c b/drivers/iio/adc/hx711.c
> index 823fd74f9cf95..062d6860da7d6 100644
> --- a/drivers/iio/adc/hx711.c
> +++ b/drivers/iio/adc/hx711.c
[ ... ]
> @@ -74,6 +76,20 @@ static int hx711_get_scale_to_gain(const int *gain_scale, int scale)
>  	return -EINVAL;
>  }
>  
> +/**
> + * struct hx711_chip_info - per-variant static configuration
> + * @name: IIO device name
> + * @channels: channel specification array
> + * @num_channels: number of entries in @channels
> + * @iio_info: IIO info ops for this variant
> + */
> +struct hx711_chip_info {
> +	const char			*name;
> +	const struct iio_chan_spec	*channels __counted_by_ptr(num_channels);

Does this cause a build failure? The __counted_by_ptr macro does not appear 
to be defined in the kernel headers, which will result in a syntax error 
during compilation.

> +	unsigned int			num_channels;
> +	const struct iio_info		*iio_info;
> +};
> +
[ ... ]
> @@ -473,6 +498,12 @@ static int hx711_probe(struct platform_device *pdev)
>  
>  	mutex_init(&hx711_data->lock);
>  
> +	chip_info = device_get_match_data(dev);
> +	if (!chip_info)
> +		return dev_err_probe(dev, -ENODEV, "missing driver data\n");

Does this cause a regression for legacy non-DT platform devices?

The device_get_match_data function relies on a firmware node being present. 
If a platform device is registered by name without a device tree or ACPI 
node, this will return NULL.

Since there is no fallback behavior or id_table provided for name-based 
matching, this now unconditionally fails the probe with -ENODEV, whereas 
previously the driver fell back to the default configuration.

> +
> +	hx711_data->chip_info = chip_info;
> +

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Sashiko AI review · https://sashiko.dev/#/patchset/20260518220228.63322-1-piyushpatle228@gmail.com?part=6