iio: imu: adis: assign value only if return code zero in read funcs

The inline read functions in the ADIS library don't check the return value
of the `adis_read_reg()` function and assign the value of `tmp` regardless.

Fix this by checking if return value is zero and only then assigning the
value of `tmp`.

No known case of the callers of this function incorrectly using the
value, but best to stop any potential risk here.
Not suitable for stable due to no known actual bugs caused by this
issue.

Fixes: 57a1228a06b7a ("iio:imu:adis: Add support for 32bit registers")
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h
index 4c53815bb729a84c51a29f5a6a3c511b2e09a9be..92aae14593bf02a62948709863b89173f1caedd2 100644 (file)
--- a/include/linux/iio/imu/adis.h
+++ b/include/linux/iio/imu/adis.h
@@ -129,7 +129,8 @@ static inline int adis_read_reg_16(struct adis *adis, unsigned int reg,
        int ret;
 
        ret = adis_read_reg(adis, reg, &tmp, 2);
-       *val = tmp;
+       if (ret == 0)
+               *val = tmp;
 
        return ret;
 }
@@ -147,7 +148,8 @@ static inline int adis_read_reg_32(struct adis *adis, unsigned int reg,
        int ret;
 
        ret = adis_read_reg(adis, reg, &tmp, 4);
-       *val = tmp;
+       if (ret == 0)
+               *val = tmp;
 
        return ret;
 }