diff --git a/arch/mips/rb532/gpio.c b/arch/mips/rb532/gpio.c
index 37de05d595e725ebdc59513181d3f43709ce1cb4..6c47dfeb7be326bf2dc4c5a7a1cbb1984b87efec 100644
--- a/arch/mips/rb532/gpio.c
+++ b/arch/mips/rb532/gpio.c
@@ -185,7 +185,7 @@ int __init rb532_gpio_init(void)
 	struct resource *r;
 
 	r = rb532_gpio_reg0_res;
-	rb532_gpio_chip->regbase = ioremap_nocache(r->start, r->end - r->start);
+	rb532_gpio_chip->regbase = ioremap_nocache(r->start, resource_size(r));
 
 	if (!rb532_gpio_chip->regbase) {
 		printk(KERN_ERR "rb532: cannot remap GPIO register 0\n");