[PATCH 4.4 036/118] iio: accel: kxsd9: Fix scaling bug

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From	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Newsgroups	linux.kernel
Subject	[PATCH 4.4 036/118] iio: accel: kxsd9: Fix scaling bug
Date	Thu, 22 Sep 2016 19:40:02 +0200
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4.4-stable review patch.  If anyone has any objections, please let me know.

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

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/iio/accel/kxsd9.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/iio/accel/kxsd9.c
+++ b/drivers/iio/accel/kxsd9.c
@@ -166,6 +166,7 @@ static int kxsd9_read_raw(struct iio_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;

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[PATCH 4.4 036/118] iio: accel: kxsd9: Fix scaling bug Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-09-22 19:40 +0200

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