diff options
| author | Paer-Olof Haakansson <par-olof.hakansson@stericsson.com> | 2012-05-10 10:41:55 +0200 |
|---|---|---|
| committer | Mathieu J. Poirier <mathieu.poirier@linaro.org> | 2012-09-25 09:37:06 -0600 |
| commit | 997a88a15aa6b98732341daf54fec6f116982408 (patch) | |
| tree | 7db677b90f19867551364ca41927fa5d8b5f9255 /drivers/power | |
| parent | cf0886a6e03f2de0735ee8aa8dc674ca1510972d (diff) | |
power: Overflow in current calculation
When calculating the average current the nominator will
overflow when the charging current is high.
Signed-off-by: Henrik Sölver <henrik.solver@stericsson.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Par-Olof HAKANSSON <par-olof.hakansson@stericsson.com>
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
Diffstat (limited to 'drivers/power')
| -rw-r--r-- | drivers/power/ab8500_fg.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/power/ab8500_fg.c b/drivers/power/ab8500_fg.c index 46010ecaaf0b..7c421504f18a 100644 --- a/drivers/power/ab8500_fg.c +++ b/drivers/power/ab8500_fg.c @@ -805,15 +805,13 @@ static void ab8500_fg_acc_cur_work(struct work_struct *work) /* * Convert to unit value in mA - * Full scale input voltage is - * 66.660mV => LSB = 66.660mV/(4096*res) = 1.627mA - * Given a 250ms conversion cycle time the LSB corresponds - * to 112.9 nAh. Convert to current by dividing by the conversion + * by dividing by the conversion * time in hours (= samples / (3600 * 4)h) - * 112.9nAh assumes 10mOhm, but fg_res is in 0.1mOhm + * and multiply with 1000 */ - di->avg_curr = (val * QLSB_NANO_AMP_HOURS_X10 * 36) / - (1000 * di->bat->fg_res * (di->fg_samples / 4)); + + di->avg_curr = (di->accu_charge * 36) / + ((di->fg_samples / 4) * 10); di->flags.conv_done = true; @@ -821,6 +819,9 @@ static void ab8500_fg_acc_cur_work(struct work_struct *work) queue_work(di->fg_wq, &di->fg_work); + dev_dbg(di->dev, + "fg_res: %d, fg_samples: %d, gasg: %d, accu_charge: %d\n", + di->bat->fg_res, di->fg_samples, val, di->accu_charge); return; exit: dev_err(di->dev, |