From: Vivien Didelot <[email protected]>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit ccd32e735de7a941906e093f8dca924bb05c5794 upstream.

An integer overflow occurs in the calculation of RHlinear when the
relative humidity is greater than around 30%. The consequence is a subtle
(but noticeable) error in the resulting humidity measurement.

Signed-off-by: Vivien Didelot <[email protected]>
Signed-off-by: Jean Delvare <[email protected]>
Cc: Jonathan Cameron <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>
---
 drivers/hwmon/sht15.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/sht15.c b/drivers/hwmon/sht15.c
index a610e78..38a41d2 100644
--- a/drivers/hwmon/sht15.c
+++ b/drivers/hwmon/sht15.c
@@ -333,11 +333,11 @@ static inline int sht15_calc_humid(struct sht15_data 
*data)
 
        const int c1 = -4;
        const int c2 = 40500; /* x 10 ^ -6 */
-       const int c3 = -2800; /* x10 ^ -9 */
+       const int c3 = -28; /* x 10 ^ -7 */
 
        RHlinear = c1*1000
                + c2 * data->val_humid/1000
-               + (data->val_humid * data->val_humid * c3)/1000000;
+               + (data->val_humid * data->val_humid * c3) / 10000;
        return (temp - 25000) * (10000 + 80 * data->val_humid)
                / 1000000 + RHlinear;
 }
-- 
1.7.4.4

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