drivers: gpio_mcux_igpio: fix code disabling the interrupt

When disabling the interrupt current implementation of the
gpio_pin_interrupt_configure function will first reconfigure the
interrupt to be active on gpio low level.
Since the pin interrupt is enabled if the gpio pin level happens
to be low at the time the interrupt will trigger immediately.
Rewrite the function to disable the interrupt in a safe manner.

Signed-off-by: Frank Li <lgl88911@163.com>

drivers/gpio/gpio_mcux_igpio.c

@@ -123,6 +123,17 @@ static int mcux_igpio_pin_interrupt_configure(struct device *dev,
 	u8_t icr;
 	int shift;
 
+	if (mode == GPIO_INT_MODE_DISABLED) {
+		key = irq_lock();
+
+		WRITE_BIT(base->IMR, pin, 0);
+		WRITE_BIT(data->pin_callback_enables, pin, 0);
+
+		irq_unlock(key);
+
+		return 0;
+	}
+
 	if ((mode == GPIO_INT_MODE_EDGE) && (trig == GPIO_INT_TRIG_LOW)) {
 		icr = 3;
 	} else if ((mode == GPIO_INT_MODE_EDGE) &&
@@ -148,10 +159,9 @@ static int mcux_igpio_pin_interrupt_configure(struct device *dev,
 	key = irq_lock();
 
 	WRITE_BIT(base->EDGE_SEL, pin, trig == GPIO_INT_TRIG_BOTH);
-	WRITE_BIT(base->ISR, pin, mode != GPIO_INT_MODE_DISABLED);
-	WRITE_BIT(base->IMR, pin, mode != GPIO_INT_MODE_DISABLED);
-	WRITE_BIT(data->pin_callback_enables, pin,
-		  mode != GPIO_INT_MODE_DISABLED);
+	WRITE_BIT(base->ISR, pin, 1);
+	WRITE_BIT(base->IMR, pin, 1);
+	WRITE_BIT(data->pin_callback_enables, pin, 1);
 
 	irq_unlock(key);