diff options
| author | Vivien Didelot <vivien.didelot@savoirfairelinux.com> | 2011-03-21 17:59:35 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-03-23 12:50:46 -0700 |
| commit | 4e3837bb22675cef56b921230f7604fe1a451a5f (patch) | |
| tree | bcd51f4b49cc95027ece9bab0d2236054476ea25 | |
| parent | c5243dd839aca1011b90ff0d810f4d6ea927f18f (diff) | |
hwmon: (sht15) Fix integer overflow in humidity calculation
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 <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | 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 a610e7880fb3..38a41d27f3da 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; } |