Re: [PATCH v11 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] The driver now unconditionally fails to probe if `device_get_match_data()` returns NULL, which breaks legacy platform device instantiation.
- [Low] The patch uses an undefined macro `__counted_by_ptr` in the definition of `struct hx711_chip_info`, causing a syntax error and build failure.
--

commit 9bf695b7a4a3ec692793615e524f77137dfcf73f
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. This prepares the driver for
supporting more compatible hardware variants.

> No functional change for existing HX711 users.

[Severity: High]
Is this description accurate? For legacy platform devices instantiated by
name, the newly added match data check prevents the driver from probing.

> 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);

[Severity: Low]
Does this compile? The macro __counted_by_ptr is not defined anywhere in
the kernel headers, which causes a syntax error and build failure.

> +	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");

[Severity: High]
Will this break legacy platform device instantiation?

For devices instantiated manually via board files matching the driver name
hx711-gpio, device_get_match_data() will return NULL because the driver
does not provide a platform_device_id table. 

Prior to this patch, the probe function ran successfully for these devices.
Now it aborts with -ENODEV.

> +
> +	hx711_data->chip_info = chip_info;
> +
>  	/*

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260603184859.89693-1-piyushpatle228@gmail.com?part=6