diff --git a/drivers/misc/atmel-ssc.c b/drivers/misc/atmel-ssc.c
index 4afffe6..769a4e8 100644
--- a/drivers/misc/atmel-ssc.c
+++ b/drivers/misc/atmel-ssc.c
@@ -95,7 +95,7 @@
 	}
 
 	ssc->pdev = pdev;
-	ssc->regs = ioremap(regs->start, regs->end - regs->start + 1);
+	ssc->regs = ioremap(regs->start, resource_size(regs));
 	if (!ssc->regs) {
 		dev_dbg(&pdev->dev, "ioremap failed\n");
 		retval = -EINVAL;