diff --git a/drivers/rtc/mc13783-rtc.c b/drivers/rtc/mc13783-rtc.c
index b6e1501..6ea9137 100644
--- a/drivers/rtc/mc13783-rtc.c
+++ b/drivers/rtc/mc13783-rtc.c
@@ -77,7 +77,7 @@
 	return 0;
 }
 
-void rtc_set(struct rtc_time *rtc)
+int rtc_set(struct rtc_time *rtc)
 {
 	u32 time, day, reg;
 
@@ -86,7 +86,7 @@
 		slave = spi_setup_slave(1, 0, 1000000,
 				SPI_MODE_2 | SPI_CS_HIGH);
 		if (!slave)
-			return;
+			return -1;
 	}
 
 	time = mktime(rtc->tm_year, rtc->tm_mon, rtc->tm_mday,
@@ -95,7 +95,7 @@
 	time %= 86400;
 
 	if (spi_claim_bus(slave))
-		return;
+		return -1;
 
 	reg = 0x2c000000 | day | 0x80000000;
 	spi_xfer(slave, 32, (uchar *)&reg, (uchar *)&day,
@@ -106,6 +106,8 @@
 			SPI_XFER_BEGIN | SPI_XFER_END);
 
 	spi_release_bus(slave);
+
+	return -1;
 }
 
 void rtc_reset(void)