serial: sh-sci: Updated calculation of bit error rate and bit rate
Currently, the decimal point is discarded calculation of BRR.
Therefore, it can not calculate a value close to the correct value.
This patch fixes this problem by using DIV_ROUND_CLOSEST.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 26dad3e..2ba4206 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -1789,11 +1789,13 @@
for (sr = 8; sr <= 32; sr++) {
for (c = 0; c <= 3; c++) {
/* integerized formulas from HSCIF documentation */
- br = freq / (sr * (1 << (2 * c + 1)) * bps) - 1;
+ br = DIV_ROUND_CLOSEST(freq, (sr *
+ (1 << (2 * c + 1)) * bps)) - 1;
if (br < 0 || br > 255)
continue;
- err = freq / ((br + 1) * bps * sr *
- (1 << (2 * c + 1)) / 1000) - 1000;
+ err = DIV_ROUND_CLOSEST(freq, ((br + 1) * bps * sr *
+ (1 << (2 * c + 1)) / 1000)) -
+ 1000;
if (min_err > err) {
min_err = err;
*brr = br;