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 13:04:16 -0700 |
| commit | 61493eba2918294ee62855d2943aa563aa301c0d (patch) | |
| tree | 1f980d7a54b0ce8fe9459165ad3eceb4a4f955d9 | |
| parent | de988be1f66ecc6ea96c11dac2e4c5bc44de9615 (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; } |