diff --git a/drivers/gpio/gpio-tz1090-pdc.c b/drivers/gpio/gpio-tz1090-pdc.c
index d7536226b847..ede7e403ffde 100644
--- a/drivers/gpio/gpio-tz1090-pdc.c
+++ b/drivers/gpio/gpio-tz1090-pdc.c
@@ -190,7 +190,7 @@ static int tz1090_pdc_gpio_probe(struct platform_device *pdev)
 
 	/* Ioremap the registers */
 	priv->reg = devm_ioremap(&pdev->dev, res_regs->start,
-				 res_regs->end - res_regs->start);
+				 resource_size(res_regs));
 	if (!priv->reg) {
 		dev_err(&pdev->dev, "unable to ioremap registers\n");
 		return -ENOMEM;