Re: [PATCH 2/2] iio: Handle enumerated properties with gaps

[Jonathan Cameron <jic23@jic23.retrosnub.co.uk>]

On Mon, 22 Apr 2019 11:32:57 +0300
Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:

> From: Lars-Peter Clausen <lars@metafoo.de>
> 
> Some enums might have gaps or reserved values in the middle of their value
> range. E.g. consider a 2-bit enum where the values 0, 1 and 3 have a
> meaning, but 2 is a reserved value and can not be used.
> 
> Add support for such enums to the IIO enum helper functions. A reserved
> values is marked by setting its entry in the items array to NULL rather
> than the normal descriptive string value.
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Looks good, subject to the whole gaps parameter discussion on patch
1.

Thanks,

Jonathan

> ---
>  drivers/iio/industrialio-core.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index f2ebca65f964..c141a29bf446 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -447,8 +447,11 @@ ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
>  	if (!e->num_items)
>  		return 0;
>  
> -	for (i = 0; i < e->num_items; ++i)
> +	for (i = 0; i < e->num_items; ++i) {
> +		if (!e->items[i])
> +			continue;
>  		len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]);
> +	}
>  
>  	/* replace last space with a newline */
>  	buf[len - 1] = '\n';
> @@ -469,7 +472,7 @@ ssize_t iio_enum_read(struct iio_dev *indio_dev,
>  	i = e->get(indio_dev, chan);
>  	if (i < 0)
>  		return i;
> -	else if (i >= e->num_items)
> +	else if (i >= e->num_items || !e->items[i])
>  		return -EINVAL;
>  
>  	return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]);
> @@ -486,7 +489,8 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
>  	if (!e->set)
>  		return -EINVAL;
>  
> -	ret = __sysfs_match_string(e->items, e->num_items, buf);
> +	ret = __sysfs_match_string_with_gaps(e->items, e->num_items,
> +					     buf, true);
>  	if (ret < 0)
>  		return ret;
>