From: Lars-Peter Clausen <[email protected]>
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 <[email protected]>
Signed-off-by: Alexandru Ardelean <[email protected]>
---
Changelog v7 -> v8:
* https://lore.kernel.org/linux-iio/[email protected]/
* dropped patch 'lib/string.c: add __sysfs_match_string_with_gaps() helper'
* merged __sysfs_match_string_with_gaps into drivers/iio/industrial-core.c
as iio_sysfs_match_string_with_gaps()
drivers/iio/industrialio-core.c | 39 ++++++++++++++++++++++++++++++---
1 file changed, 36 insertions(+), 3 deletions(-)
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index e9ee9363fed0..db20e2ab437d 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -169,6 +169,36 @@ static const char * const iio_chan_info_postfix[] = {
[IIO_CHAN_INFO_CALIBAMBIENT] = "calibambient",
};
+/**
+ * iio_sysfs_match_string_with_gaps - matches given string in an array with gaps
+ * @array: array of strings
+ * @n: number of strings in the array
+ * @str: string to match with
+ *
+ * Returns index of @str in the @array or -EINVAL, similar to match_string().
+ * Uses sysfs_streq instead of strcmp for matching.
+ *
+ * This routine will look for a string in an array of strings.
+ * The search will continue until the element is found or the n-th element
+ * is reached, regardless of any NULL elements in the array.
+ */
+static int iio_sysfs_match_string_with_gaps(const char * const *array, size_t n,
+ const char *str)
+{
+ const char *item;
+ int index;
+
+ for (index = 0; index < n; index++) {
+ item = array[index];
+ if (!item)
+ continue;
+ if (sysfs_streq(item, str))
+ return index;
+ }
+
+ return -EINVAL;
+}
+
#if defined(CONFIG_DEBUG_FS)
/*
* There's also a CONFIG_DEBUG_FS guard in include/linux/iio/iio.h for
@@ -470,8 +500,11 @@ 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';
@@ -492,7 +525,7 @@ 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]);
@@ -509,7 +542,7 @@ 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 = iio_sysfs_match_string_with_gaps(e->items, e->num_items, buf);
if (ret < 0)
return ret;
--
2.17.1
On Thu, 7 Jan 2021 13:20:49 +0200
Alexandru Ardelean <[email protected]> wrote:
> From: Lars-Peter Clausen <[email protected]>
>
> 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 <[email protected]>
> Signed-off-by: Alexandru Ardelean <[email protected]>
Applied to the togreg branch of iio.git and pushed out as testing for all
the normal autobuilder related reasons.
Note I can still rebase so if anyone wants to add tags or comment it's
not yet too late!
Jonathan
> ---
>
> Changelog v7 -> v8:
> * https://lore.kernel.org/linux-iio/[email protected]/
> * dropped patch 'lib/string.c: add __sysfs_match_string_with_gaps() helper'
> * merged __sysfs_match_string_with_gaps into drivers/iio/industrial-core.c
> as iio_sysfs_match_string_with_gaps()
>
> drivers/iio/industrialio-core.c | 39 ++++++++++++++++++++++++++++++---
> 1 file changed, 36 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index e9ee9363fed0..db20e2ab437d 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -169,6 +169,36 @@ static const char * const iio_chan_info_postfix[] = {
> [IIO_CHAN_INFO_CALIBAMBIENT] = "calibambient",
> };
>
> +/**
> + * iio_sysfs_match_string_with_gaps - matches given string in an array with gaps
> + * @array: array of strings
> + * @n: number of strings in the array
> + * @str: string to match with
> + *
> + * Returns index of @str in the @array or -EINVAL, similar to match_string().
> + * Uses sysfs_streq instead of strcmp for matching.
> + *
> + * This routine will look for a string in an array of strings.
> + * The search will continue until the element is found or the n-th element
> + * is reached, regardless of any NULL elements in the array.
> + */
> +static int iio_sysfs_match_string_with_gaps(const char * const *array, size_t n,
> + const char *str)
> +{
> + const char *item;
> + int index;
> +
> + for (index = 0; index < n; index++) {
> + item = array[index];
> + if (!item)
> + continue;
> + if (sysfs_streq(item, str))
> + return index;
> + }
> +
> + return -EINVAL;
> +}
> +
> #if defined(CONFIG_DEBUG_FS)
> /*
> * There's also a CONFIG_DEBUG_FS guard in include/linux/iio/iio.h for
> @@ -470,8 +500,11 @@ 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';
> @@ -492,7 +525,7 @@ 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]);
> @@ -509,7 +542,7 @@ 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 = iio_sysfs_match_string_with_gaps(e->items, e->num_items, buf);
> if (ret < 0)
> return ret;
>
On Sat, Jan 9, 2021 at 9:23 PM Jonathan Cameron <[email protected]> wrote:
>
> On Thu, 7 Jan 2021 13:20:49 +0200
> Alexandru Ardelean <[email protected]> wrote:
>
> > From: Lars-Peter Clausen <[email protected]>
> >
> > 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 <[email protected]>
> > Signed-off-by: Alexandru Ardelean <[email protected]>
>
> Applied to the togreg branch of iio.git and pushed out as testing for all
> the normal autobuilder related reasons.
>
> Note I can still rebase so if anyone wants to add tags or comment it's
> not yet too late!
Free to add
Reviewed-by: Andy Shevchenko <[email protected]>
--
With Best Regards,
Andy Shevchenko