[34-longterm 053/247] ds2760_battery: Fix calculation of time_to_empty_now

From: Paul Gortmaker
Date: Thu Jun 23 2011 - 13:33:10 EST

From: Sven Neumann <s.neumann@xxxxxxxxxxxx>

This is a commit scheduled for the next v2.6.34 longterm release.
If you see a problem with using this for longterm, please comment.

commit 86af95039b69a90db15294eb1f9c147f1df0a8ea upstream.

A check against division by zero was modified in commit b0525b48.
Since this change time_to_empty_now is always reported as zero
while the battery is discharging and as a negative value while
the battery is charging. This is because current is negative while
the battery is discharging.

Fix the check introduced by commit b0525b48 so that time_to_empty_now
is reported correctly during discharge and as zero while charging.

Signed-off-by: Sven Neumann <s.neumann@xxxxxxxxxxxx>
Acked-by: Daniel Mack <daniel@xxxxxxxx>
Signed-off-by: Anton Vorontsov <cbouatmailru@xxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
drivers/power/ds2760_battery.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/power/ds2760_battery.c b/drivers/power/ds2760_battery.c
index 3bf8d1f..4e13ebd 100644
--- a/drivers/power/ds2760_battery.c
+++ b/drivers/power/ds2760_battery.c
@@ -212,7 +212,7 @@ static int ds2760_battery_read_status(struct ds2760_device_info *di)
if (di->rem_capacity > 100)
di->rem_capacity = 100;

- if (di->current_uA >= 100L)
+ if (di->current_uA < -100L)
di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L)
/ (di->current_uA / 100L);

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