diff --git a/drivers/watchdog/realtek_otto_wdt.c b/drivers/watchdog/realtek_otto_wdt.c
index 2c30ddd574c5..1495e8a8cbb5 100644
--- a/drivers/watchdog/realtek_otto_wdt.c
+++ b/drivers/watchdog/realtek_otto_wdt.c
@@ -114,12 +114,6 @@ static int otto_wdt_tick_ms(struct otto_wdt_ctrl *ctrl, int prescale)
  * the value stored in those fields. This means each phase will run for at least
  * one tick, so small values need to be clamped to correctly reflect the timeout.
  */
-static inline unsigned int div_round_ticks(unsigned int val, unsigned int tick_duration,
-		unsigned int min_ticks)
-{
-	return max(min_ticks, DIV_ROUND_UP(val, tick_duration));
-}
-
 static int otto_wdt_determine_timeouts(struct watchdog_device *wdev, unsigned int timeout,
 		unsigned int pretimeout)
 {
@@ -140,9 +134,9 @@ static int otto_wdt_determine_timeouts(struct watchdog_device *wdev, unsigned in
 			return -EINVAL;
 
 		tick_ms = otto_wdt_tick_ms(ctrl, prescale);
-		total_ticks = div_round_ticks(timeout_ms, tick_ms, 2);
-		phase1_ticks = div_round_ticks(timeout_ms - pretimeout_ms, tick_ms, 1);
-		phase2_ticks = total_ticks - phase1_ticks;
+		total_ticks = max(2, DIV_ROUND_UP(timeout_ms, tick_ms));
+		phase2_ticks = max(1, pretimeout_ms / tick_ms);
+		phase1_ticks = total_ticks - phase2_ticks;
 
 		prescale_next++;
 	} while (phase1_ticks > OTTO_WDT_PHASE_TICKS_MAX