Re: [PATCH v2] iio: fix iio_format_avail_range() printing for none IIO_VAL_INT

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 18 Jul 2022 15:07:06 +0200
Jean-Baptiste Maneyrol <jmaneyrol@invensense.com> wrote:

> From: Fawzi Khaber <fawzi.khaber@tdk.com>
> 
> iio_format_avail_range() should print range as follow [min, step, max], so
> the function was previously calling iio_format_list() with length = 3,
> length variable refers to the array size of values not the number of
> elements. In case of non IIO_VAL_INT values each element has integer part
> and decimal part. With length = 3 this would cause premature end of loop
> and result in printing only one element.
> 
> Signed-off-by: Fawzi Khaber <fawzi.khaber@tdk.com>
> Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
> Fixes: eda20ba1e25e ("iio: core: Consolidate iio_format_avail_{list,range}()")
As I'm hoping to sneak in a late pull request for the coming merge window
(as the cycle has been delayed), I've picked this on up on the togreg branch of iio.git.
+ marked for stable.

Thanks,

Jonathan

> ---
>  drivers/iio/industrialio-core.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index 358b909298c0..0f4dbda3b9d3 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -812,7 +812,23 @@ static ssize_t iio_format_avail_list(char *buf, const int *vals,
>  
>  static ssize_t iio_format_avail_range(char *buf, const int *vals, int type)
>  {
> -	return iio_format_list(buf, vals, type, 3, "[", "]");
> +	int length;
> +
> +	/*
> +	 * length refers to the array size , not the number of elements.
> +	 * The purpose is to print the range [min , step ,max] so length should
> +	 * be 3 in case of int, and 6 for other types.
> +	 */
> +	switch (type) {
> +	case IIO_VAL_INT:
> +		length = 3;
> +		break;
> +	default:
> +		length = 6;
> +		break;
> +	}
> +
> +	return iio_format_list(buf, vals, type, length, "[", "]");
>  }
>  
>  static ssize_t iio_read_channel_info_avail(struct device *dev,