rtc-vr41xx: use resource_size()

Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-vr41xx.c b/drivers/rtc/rtc-vr41xx.c
index fadddac..c324424 100644
--- a/drivers/rtc/rtc-vr41xx.c
+++ b/drivers/rtc/rtc-vr41xx.c
@@ -327,7 +327,7 @@
 	if (!res)
 		return -EBUSY;
 
-	rtc1_base = ioremap(res->start, res->end - res->start + 1);
+	rtc1_base = ioremap(res->start, resource_size(res));
 	if (!rtc1_base)
 		return -EBUSY;
 
@@ -337,7 +337,7 @@
 		goto err_rtc1_iounmap;
 	}
 
-	rtc2_base = ioremap(res->start, res->end - res->start + 1);
+	rtc2_base = ioremap(res->start, resource_size(res));
 	if (!rtc2_base) {
 		retval = -EBUSY;
 		goto err_rtc1_iounmap;