[PATCH] iio: imu: adis16400: Fix sign extension

Rasmus Villemoes
2015-01-22T23:34:14Z

The intention is obviously to sign-extend a 12 bit quantity. But
because of C's promotion rules, the assignment is equivalent to "val16
&= 0xfff;". Use the proper API for this.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
---
drivers/iio/imu/adis16400_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/imu/adis16400_core.c b/drivers/iio/imu/adis16400_core.c
index b70873de04ea..fa795dcd5f75 100644
--- a/drivers/iio/imu/adis16400_core.c
+++ b/drivers/iio/imu/adis16400_core.c
@@ -26,6 +26,7 @@
#include <linux/list.h>
#include <linux/module.h>
#include <linux/debugfs.h>
+#include <linux/bitops.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
@@ -414,7 +415,7 @@ static int adis16400_read_raw(struct iio_dev *indio_dev,
mutex_unlock(&indio_dev->mlock);
if (ret)
return ret;
- val16 = ((val16 & 0xFFF) << 4) >> 4;
+ val16 = sign_extend32(val16, 11);
*val = val16;
return IIO_VAL_INT;
case IIO_CHAN_INFO_OFFSET:
--
2.1.3