[PATCH 4.18 066/145] iio: ad9523: Fix return value for ad952x_store()

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Lars-Peter Clausen <lars@xxxxxxxxxx>

commit 9a5094ca29ea9b1da301b31fd377c0c0c4c23034 upstream.

A sysfs write callback function needs to either return the number of
consumed characters or an error.

The ad952x_store() function currently returns 0 if the input value was "0",
this will signal that no characters have been consumed and the function
will be called repeatedly in a loop indefinitely. Fix this by returning
number of supplied characters to indicate that the whole input string has
been consumed.

Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Fixes: cd1678f96329 ("iio: frequency: New driver for AD9523 SPI Low Jitter Clock Generator")
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/iio/frequency/ad9523.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/iio/frequency/ad9523.c
+++ b/drivers/iio/frequency/ad9523.c
@@ -508,7 +508,7 @@ static ssize_t ad9523_store(struct devic
 		return ret;
 
 	if (!state)
-		return 0;
+		return len;
 
 	mutex_lock(&indio_dev->mlock);
 	switch ((u32)this_attr->address) {