ds2760_battery: Fix integer overflow for time_to_empty_now

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>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
This commit is contained in:
Daniel Mack 2009-07-24 15:08:11 +02:00 committed by Anton Vorontsov
parent 83a8af0d31
commit b0525b48f0

View File

@ -211,9 +211,9 @@ static int ds2760_battery_read_status(struct ds2760_device_info *di)
if (di->rem_capacity > 100)
di->rem_capacity = 100;
if (di->current_uA)
di->life_sec = -((di->accum_current_uAh - di->empty_uAh) *
3600L) / di->current_uA;
if (di->current_uA >= 100L)
di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L)
/ (di->current_uA / 100L);
else
di->life_sec = 0;