diff --git a/drivers/rtc/rtc-ds1553.c b/drivers/rtc/rtc-ds1553.c
index ecafbad..762521a 100644
--- a/drivers/rtc/rtc-ds1553.c
+++ b/drivers/rtc/rtc-ds1553.c
@@ -226,7 +226,7 @@
 	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 
 	if (pdata->irq < 0)
-		return -ENOIOCTLCMD;
+		return -ENOIOCTLCMD; /* fall back into rtc-dev's emulation */
 	switch (cmd) {
 	case RTC_AIE_OFF:
 		pdata->irqen &= ~RTC_AF;