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Subject[PATCH] ds2760: fix integer overflow for time_to_empty_now
Date
On the device we're currently developing, battery sizes of ~2.8Ah and
current flow of ~600mA are typical.

With that values, the life_sec computation overflows due to the
multiplication by 3600.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
Cc: Matt Reimer <mreimer@vpop.net>
Cc: Anton Vorontsov <cbou@mail.ru>

Signed-off-by: Daniel Mack <daniel@caiaq.de>
---
drivers/power/ds2760_battery.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/power/ds2760_battery.c b/drivers/power/ds2760_battery.c
index d545fee..5d30dc0 100644
--- a/drivers/power/ds2760_battery.c
+++ b/drivers/power/ds2760_battery.c
@@ -212,8 +212,8 @@ static int ds2760_battery_read_status(struct ds2760_device_info *di)
di->rem_capacity = 100;

if (di->current_uA)
- di->life_sec = -((di->accum_current_uAh - di->empty_uAh) *
- 3600L) / di->current_uA;
+ di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L)
+ / (di->current_uA / 100L);
else
di->life_sec = 0;

--
1.6.3.1


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