diff mbox series

rtc: pcf2123: fix negative offset rounding

Message ID 20190619131753.14802-1-alexandre.belloni@bootlin.com
State Accepted
Headers show
Series rtc: pcf2123: fix negative offset rounding | expand

Commit Message

Alexandre Belloni June 19, 2019, 1:17 p.m. UTC
Using result = (value + divisor/2) / divisor is rounding values up and only
works well for positive values. Instead use DIV_ROUND_CLOSEST which does
the correct thing.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
 drivers/rtc/rtc-pcf2123.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/rtc/rtc-pcf2123.c b/drivers/rtc/rtc-pcf2123.c
index 39da8b214275..80a53d2dc813 100644
--- a/drivers/rtc/rtc-pcf2123.c
+++ b/drivers/rtc/rtc-pcf2123.c
@@ -244,7 +244,7 @@  static int pcf2123_set_offset(struct device *dev, long offset)
 	else if (offset < OFFSET_STEP * -128)
 		reg = -128;
 	else
-		reg = (s8)((offset + (OFFSET_STEP >> 1)) / OFFSET_STEP);
+		reg = DIV_ROUND_CLOSEST(offset, OFFSET_STEP);
 
 	/* choose fine offset only for odd values in the normal range */
 	if (reg & 1 && reg <= 63 && reg >= -64) {