Hello!

On 8/30/2018 5:39 AM, Nguyen An Hoan wrote:

From: Hoan Nguyen An <[email protected]>

About the formula for temperature calculation
[reg] = [temp] * a + b <=> [temp] = ([reg] - b) / a

Using "(mcelsius * tsc-> coef.aX) / 1000" instead of "DIV_ROUND_CLOSEST(mcelsius, 1000) 
* tsc-> coef.aX"
to avoid and reduce inaccuracy due to rounding the integer division.

Signed-off-by: Hoan Nguyen An <[email protected]>
---
  drivers/thermal/rcar_gen3_thermal.c | 7 +++----
  1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/thermal/rcar_gen3_thermal.c 
b/drivers/thermal/rcar_gen3_thermal.c
index 7aed533..dbb31b8 100644
--- a/drivers/thermal/rcar_gen3_thermal.c
+++ b/drivers/thermal/rcar_gen3_thermal.c
@@ -185,11 +185,10 @@ static int rcar_gen3_thermal_get_temp(void *devdata, int 
*temp)
  static int rcar_gen3_thermal_mcelsius_to_temp(struct rcar_gen3_thermal_tsc 
*tsc,
                                              int mcelsius)
  {
-       int celsius, val1, val2;
+       int val1, val2;
- celsius = DIV_ROUND_CLOSEST(mcelsius, 1000);
-       val1 = celsius * tsc->coef.a1 + tsc->coef.b1;
-       val2 = celsius * tsc->coef.a2 + tsc->coef.b2;
+       val1 = (mcelsius * tsc->coef.a1)/1000 + tsc->coef.b1;
+       val2 = (mcelsius * tsc->coef.a2)/1000 + tsc->coef.b2;

Please be consistent and enclose / in sopaces the same as you do for other operators.

[...]

MBR, Sergei

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