1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/watchdog/at32ap700x_wdt.c b/drivers/watchdog/at32ap700x_wdt.c
index e8ae638e5804..037847923dcb 100644
--- a/drivers/watchdog/at32ap700x_wdt.c
+++ b/drivers/watchdog/at32ap700x_wdt.c
@@ -326,7 +326,7 @@ static int __init at32_wdt_probe(struct platform_device *pdev)
                 return -ENOMEM;
         }
 
-        wdt->regs = ioremap(regs->start, regs->end - regs->start + 1);
+        wdt->regs = ioremap(regs->start, resource_size(regs));
         if (!wdt->regs) {
                 ret = -ENOMEM;
                 dev_dbg(&pdev->dev, "could not map I/O memory\n");