[PATCH] ds2760: fix integer overflow for time_to_empty_now

[Daniel Mack]

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@xxxxxxxx>
Cc: Szabolcs Gyurko <szabolcs.gyurko@xxxxxx>
Cc: Matt Reimer <mreimer@xxxxxxxx>
Cc: Anton Vorontsov <cbou@xxxxxxx>

Signed-off-by: Daniel Mack <daniel@xxxxxxxx>
---
 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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