[PATCH 4.4 27/76] iio: imu: adis16480: assign bias value only if operation succeeded

Greg Kroah-Hartman
2020-01-22T09:57:14Z

From: Alexandru Ardelean <alexandru.ardelean@analog.com>

commit 9b742763d9d4195e823ae6ece760c9ed0500c1dc upstream.

This was found only after the whole thing with the inline functions, but
the compiler actually found something. The value of the `bias` (in
adis16480_get_calibbias()) should only be set if the read operation was
successful.

No actual known problem occurs as users of this function all
ultimately check the return value. Hence probably not stable material.

Fixes: 2f3abe6cbb6c9 ("iio:imu: Add support for the ADIS16480 and similar IMUs")
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/iio/imu/adis16480.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/iio/imu/adis16480.c
+++ b/drivers/iio/imu/adis16480.c
@@ -372,12 +372,14 @@ static int adis16480_get_calibbias(struc
case IIO_MAGN:
case IIO_PRESSURE:
ret = adis_read_reg_16(&st->adis, reg, &val16);
- *bias = sign_extend32(val16, 15);
+ if (ret == 0)
+ *bias = sign_extend32(val16, 15);
break;
case IIO_ANGL_VEL:
case IIO_ACCEL:
ret = adis_read_reg_32(&st->adis, reg, &val32);
- *bias = sign_extend32(val32, 31);
+ if (ret == 0)
+ *bias = sign_extend32(val32, 31);
break;
default:
ret = -EINVAL;