iio: querying buffer scan_mask should return 0/1
Ensure that querying the IIO buffer scan_mask returns a value of
0 or 1. Currently querying the scan mask has the value returned
by test_bit(), which returns either true or false. For some
architectures test_bit() may return -1 for true, which will appear
to return an error when returning from iio_scan_mask_query().
Additionally, it's important for the sysfs interface to consistently
return the same thing when querying the scan_mask.
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index c67d83b..fe25042 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -165,7 +165,8 @@
int ret;
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- ret = test_bit(to_iio_dev_attr(attr)->address,
+ /* Ensure ret is 0 or 1. */
+ ret = !!test_bit(to_iio_dev_attr(attr)->address,
indio_dev->buffer->scan_mask);
return sprintf(buf, "%d\n", ret);
@@ -866,7 +867,8 @@
if (!buffer->scan_mask)
return 0;
- return test_bit(bit, buffer->scan_mask);
+ /* Ensure return value is 0 or 1. */
+ return !!test_bit(bit, buffer->scan_mask);
};
EXPORT_SYMBOL_GPL(iio_scan_mask_query);