1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/rtc/rtc-m48t59.c b/drivers/rtc/rtc-m48t59.c
index 3978f4caf724..28365388fb6c 100644
--- a/drivers/rtc/rtc-m48t59.c
+++ b/drivers/rtc/rtc-m48t59.c
@@ -433,7 +433,7 @@ static int __devinit m48t59_rtc_probe(struct platform_device *pdev)
 
         if (!m48t59->ioaddr) {
                 /* ioaddr not mapped externally */
-                m48t59->ioaddr = ioremap(res->start, res->end - res->start + 1);
+                m48t59->ioaddr = ioremap(res->start, resource_size(res));
                 if (!m48t59->ioaddr)
                         goto out;
         }