shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-06 10:58:48 +09:00
Code Issues Packages Projects Releases Wiki Activity

IIO: bmp280-core.c: fix error in humidity calculation

Browse Source 
commit ed3730c435 upstream.

While calculating the compensation of the humidity there are negative values
interpreted as unsigned because of unsigned variables used.  These values as
well as the constants need to be casted to signed as indicated by the
documentation of the sensor.

Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andreas Klinger
2017-04-10 19:00:01 +02:00
committed by Greg Kroah-Hartman
parent a03176f92a
commit dfb450b2b6
1 changed files with 6 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
drivers/iio/pressure/bmp280-core.c
View File

@@ -175,11 +175,12 @@ static u32 bmp280_compensate_humidity(struct bmp280_data *data,
}
H6 = sign_extend32(tmp, 7);
var = ((s32)data->t_fine) - 76800;
var = ((((adc_humidity << 14) - (H4 << 20) - (H5 * var)) + 16384) >> 15)
* (((((((var * H6) >> 10) * (((var * H3) >> 11) + 32768)) >> 10)
+ 2097152) * H2 + 8192) >> 14);
var -= ((((var >> 15) * (var >> 15)) >> 7) * H1) >> 4;
var = ((s32)data->t_fine) - (s32)76800;
var = ((((adc_humidity << 14) - (H4 << 20) - (H5 * var))
+ (s32)16384) >> 15) * (((((((var * H6) >> 10)
* (((var * (s32)H3) >> 11) + (s32)32768)) >> 10)
+ (s32)2097152) * H2 + 8192) >> 14);
var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)H1) >> 4;
return var >> 12;
};