[PATCH 02/14] POWER: bq27x00: Improve temperature precession

From: Lars-Peter Clausen
Date: Sun Feb 06 2011 - 14:33:48 EST


This patch improves the precession of the temperature property of the bq27x00
driver.
By dividing before multiplying the current code effectively cuts of the last
decimal digit. This patch fixes it by multiplying before dividing.

Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
---
drivers/power/bq27x00_battery.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/power/bq27x00_battery.c b/drivers/power/bq27x00_battery.c
index bb043f9..4f74659 100644
--- a/drivers/power/bq27x00_battery.c
+++ b/drivers/power/bq27x00_battery.c
@@ -109,7 +109,7 @@ static int bq27x00_battery_temperature(struct bq27x00_device_info *di)
if (di->chip == BQ27500)
return temp - 2731;
else
- return ((temp >> 2) - 273) * 10;
+ return ((temp * 5) - 5463) / 2;
}

/*
--
1.7.2.3

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