[PATCH] gpio: Fix test on unsigned in lnw_irq_type()

[Roel Kluin <roel.kluin@gmail.com>]

The wrong test was used, gpio is unsigned.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
---
diff --git a/drivers/gpio/langwell_gpio.c b/drivers/gpio/langwell_gpio.c
index 5711ce5..0d0cbc0 100644
--- a/drivers/gpio/langwell_gpio.c
+++ b/drivers/gpio/langwell_gpio.c
@@ -123,8 +123,11 @@ static int lnw_irq_type(unsigned irq, unsigned type)
 	void __iomem *grer = (void __iomem *)(&lnw->reg_base->GRER[reg]);
 	void __iomem *gfer = (void __iomem *)(&lnw->reg_base->GFER[reg]);
 
-	if (gpio < 0 || gpio > lnw->chip.ngpio)
+	if (irq < lnw->irq_base || gpio > lnw->chip.ngpio ||
+			reg >= ARRAY_SIZE(lnw->reg_base->GRER)
+			reg >= ARRAY_SIZE(lnw->reg_base->GFER))
 		return -EINVAL;
+
 	spin_lock_irqsave(&lnw->lock, flags);
 	if (type & IRQ_TYPE_EDGE_RISING)
 		value = readl(grer) | BIT(gpio % 32);