Re: [PATCH] iio: adc: mcp3422: use sysfs_emit() in show functions

[Jonathan Cameron <jic23@kernel.org>]

On Sat, 19 Sep 2026 22:55:07 +0300
Angel2Eyes <thefireking@gmail.com> wrote:

> sysfs_emit() is preferred over sprintf() for sysfs show() callbacks
> since it is aware of the PAGE_SIZE buffer and has built-in size and
> alignment checks.
> 
> Convert the remaining sprintf() calls in mcp3422_show_samp_freqs() and
> mcp3422_show_scales(). The formatted output is unchanged.
> 
> Assisted-by: LLM
> Signed-off-by: Angel2Eyes <thefireking@gmail.com>
Hi.  

In the ideal case you would go further here and make us of the
read_avail() callback and appropriate _avail bitmap elements
for the channels.  Given simple nature of these two functions that
should be easy to convert.  The reason to do this is to make the
ranges etc available to in kernel users.

If you want to just make this simpler change I don't mind, but
we do need that 'well known identity' for the Sign off that
Maxwell has raised.

Jonathan

> ---
>  drivers/iio/adc/mcp3422.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/adc/mcp3422.c b/drivers/iio/adc/mcp3422.c
> index 36ba00edf..fd9e72265 100644
> --- a/drivers/iio/adc/mcp3422.c
> +++ b/drivers/iio/adc/mcp3422.c
> @@ -262,9 +262,9 @@ static ssize_t mcp3422_show_samp_freqs(struct device *dev,
>  	struct mcp3422 *adc = iio_priv(dev_to_iio_dev(dev));
>  
>  	if (adc->id > 4)
> -		return sprintf(buf, "240 60 15\n");
> +		return sysfs_emit(buf, "240 60 15\n");
>  
> -	return sprintf(buf, "240 60 15 3\n");
> +	return sysfs_emit(buf, "240 60 15 3\n");
>  }
>  
>  static ssize_t mcp3422_show_scales(struct device *dev,
> @@ -273,7 +273,7 @@ static ssize_t mcp3422_show_scales(struct device *dev,
>  	struct mcp3422 *adc = iio_priv(dev_to_iio_dev(dev));
>  	u8 sample_rate = FIELD_GET(MCP3422_SRATE_MASK, adc->config);
>  
> -	return sprintf(buf, "0.%09u 0.%09u 0.%09u 0.%09u\n",
> +	return sysfs_emit(buf, "0.%09u 0.%09u 0.%09u 0.%09u\n",
>  		mcp3422_scales[sample_rate][0],
>  		mcp3422_scales[sample_rate][1],
>  		mcp3422_scales[sample_rate][2],
> 
> base-commit: 69fa76f0af3414cc189c3b0b807cb59e327ecc00