pinctrl: at91: use gpiolib API to mark a GPIO used as an IRQ

When an IRQ is started on a GPIO line, mark this GPIO as IRQ in
the gpiolib so we can keep track of the usage centrally.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-at91.c

@@ -1325,6 +1325,31 @@ static int alt_gpio_irq_type(struct irq_data *d, unsigned type)
 	return 0;
 }
 
+static unsigned int gpio_irq_startup(struct irq_data *d)
+{
+	struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
+	unsigned	pin = d->hwirq;
+	int ret;
+
+	ret = gpio_lock_as_irq(&at91_gpio->chip, pin);
+	if (ret) {
+		dev_err(at91_gpio->chip.dev, "unable to lock pind %lu IRQ\n",
+			d->hwirq);
+		return ret;
+	}
+	gpio_irq_unmask(d);
+	return 0;
+}
+
+static void gpio_irq_shutdown(struct irq_data *d)
+{
+	struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
+	unsigned	pin = d->hwirq;
+
+	gpio_irq_mask(d);
+	gpio_unlock_as_irq(&at91_gpio->chip, pin);
+}
+
 #ifdef CONFIG_PM
 
 static u32 wakeups[MAX_GPIO_BANKS];
@@ -1399,6 +1424,8 @@ void at91_pinctrl_gpio_resume(void)
 
 static struct irq_chip gpio_irqchip = {
 	.name		= "GPIO",
+	.irq_startup	= gpio_irq_startup,
+	.irq_shutdown	= gpio_irq_shutdown,
 	.irq_disable	= gpio_irq_mask,
 	.irq_mask	= gpio_irq_mask,
 	.irq_unmask	= gpio_irq_unmask,