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



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>
Acked-by: Rodolfo Giometti <giometti@xxxxxxxx>
---
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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Relevant Pages

  • [PATCH 02/14] POWER: bq27x00: Improve temperature precession
    ... decimal digit. ... This patch fixes it by multiplying before dividing. ...
    (Linux-Kernel)
  • Re: dividing into
    ... I just don't see how that is multiplying one by three. ... terms of the number of items you end up with, just as dividing 2 pizzas ... dividing two pizzas into 8 equal pieces. ... To me, this illustrates that "dividing an object into 3 pieces" in normal English, is more like a multiplication than a division process in mathematics, since "division" in mathematics implies dividing into equal parts. ...
    (alt.usage.english)
  • Re: dividing into
    ... I suggest that mine is the common meaning as far as mathematics ... I just don't see how that is multiplying one by three. ... terms of the number of items you end up with, just as dividing 2 pizzas ... But I can't see any possibility of 4x2=8 representing the operation of dividing two pizzas into 8 equal pieces. ...
    (alt.usage.english)
  • Re: Kinda Miss TG...
    ... dividing by fractions than with multiplying by them. ... think of that as multiplying by the inversion of the fraction. ... Computing the number of photons hitting the camera sensor is just such ...
    (rec.music.classical.guitar)
  • Re: Kinda Miss TG...
    ... multiplying or dividing by a number less than 1. ... The local diesel power plant here on this tiny island runs at about ... Rest assured that I can multiply numbers too, even fractions! ... The case is clearer with dividing by fractions than with multiplying by them. ...
    (rec.music.classical.guitar)