ab8500-fg: Change current calculation

This patch updates the gas gauge constant for electric current
calculation according to hardware specification.

Signed-off-by: Benoit GAUTHIER <benoit.gauthier-xsig@stericsson.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Marcus COOPER <marcus.xm.cooper@stericsson.com>
Reviewed-by: Philippe LANGLAIS <philippe.langlais@stericsson.com>
Tested-by: Benoit GAUTHIER <benoit.gauthier-xsig@stericsson.com>
This commit is contained in:
lme00437 2012-12-12 10:07:50 +01:00 committed by Lee Jones
parent 4d3b4aa58a
commit 0577610e0e

View File

@ -36,7 +36,7 @@
#define MILLI_TO_MICRO 1000
#define FG_LSB_IN_MA 1627
#define QLSB_NANO_AMP_HOURS_X10 1129
#define QLSB_NANO_AMP_HOURS_X10 1071
#define INS_CURR_TIMEOUT (3 * HZ)
#define SEC_TO_SAMPLE(S) (S * 4)
@ -672,11 +672,11 @@ int ab8500_fg_inst_curr_finalize(struct ab8500_fg *di, int *res)
/*
* Convert to unit value in mA
* Full scale input voltage is
* 66.660mV => LSB = 66.660mV/(4096*res) = 1.627mA
* 63.160mV => LSB = 63.160mV/(4096*res) = 1.542mA
* Given a 250ms conversion cycle time the LSB corresponds
* to 112.9 nAh. Convert to current by dividing by the conversion
* to 107.1 nAh. Convert to current by dividing by the conversion
* time in hours (250ms = 1 / (3600 * 4)h)
* 112.9nAh assumes 10mOhm, but fg_res is in 0.1mOhm
* 107.1nAh assumes 10mOhm, but fg_res is in 0.1mOhm
*/
val = (val * QLSB_NANO_AMP_HOURS_X10 * 36 * 4) /
(1000 * di->bm->fg_res);