[PATCH 3.10 194/319] iio: accel: kxsd9: Fix scaling bug

Willy Tarreau
2017-02-05T19:58:28Z

From: Linus Walleij <linus.walleij@linaro.org>

commit 307fe9dd11ae44d4f8881ee449a7cbac36e1f5de upstream.

All the scaling of the KXSD9 involves multiplication with a
fraction number < 1.

However the scaling value returned from IIO_INFO_SCALE was
unpredictable as only the micros of the value was assigned, and
not the integer part, resulting in scaling like this:

$cat in_accel_scale
-1057462640.011978

Fix this by assigning zero to the integer part.

Tested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/iio/accel/kxsd9.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c
index d94c0ca..4f9d178 100644
--- a/drivers/iio/accel/kxsd9.c
+++ b/drivers/iio/accel/kxsd9.c
@@ -166,6 +166,7 @@ static int kxsd9_read_raw(struct iio_dev *indio_dev,
ret = spi_w8r8(st->us, KXSD9_READ(KXSD9_REG_CTRL_C));
if (ret < 0)
goto error_ret;
+ *val = 0;
*val2 = kxsd9_micro_scales[ret & KXSD9_FS_MASK];
ret = IIO_VAL_INT_PLUS_MICRO;
break;
--
2.8.0.rc2.1.gbe9624a