gpio: dln2: Use irqchip template

This makes the driver use the irqchip template to assign
properties to the gpio_irq_chip instead of using the
explicit calls to gpiochip_irqchip_add(). The irqchip is
instead added while adding the gpiochip.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Daniel Baluta <daniel.baluta@gmail.com>
Cc: Daniel Baluta <daniel.baluta@gmail.com>
Cc: Octavian Purdila <octavian.purdila@nxp.com>
Link: https://lore.kernel.org/r/20200722073426.38890-1-linus.walleij@linaro.org

drivers/gpio/gpio-dln2.c

@@ -440,6 +440,7 @@ static int dln2_gpio_probe(struct platform_device *pdev)
 {
 	struct dln2_gpio *dln2;
 	struct device *dev = &pdev->dev;
+	struct gpio_irq_chip *girq;
 	int pins;
 	int ret;
 
@@ -476,6 +477,15 @@ static int dln2_gpio_probe(struct platform_device *pdev)
 	dln2->gpio.direction_output = dln2_gpio_direction_output;
 	dln2->gpio.set_config = dln2_gpio_set_config;
 
+	girq = &dln2->gpio.irq;
+	girq->chip = &dln2_gpio_irqchip;
+	/* The event comes from the outside so no parent handler */
+	girq->parent_handler = NULL;
+	girq->num_parents = 0;
+	girq->parents = NULL;
+	girq->default_type = IRQ_TYPE_NONE;
+	girq->handler = handle_simple_irq;
+
 	platform_set_drvdata(pdev, dln2);
 
 	ret = devm_gpiochip_add_data(dev, &dln2->gpio, dln2);
@@ -484,13 +494,6 @@ static int dln2_gpio_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	ret = gpiochip_irqchip_add(&dln2->gpio, &dln2_gpio_irqchip, 0,
-				   handle_simple_irq, IRQ_TYPE_NONE);
-	if (ret < 0) {
-		dev_err(dev, "failed to add irq chip: %d\n", ret);
-		return ret;
-	}
-
 	ret = dln2_register_event_cb(pdev, DLN2_GPIO_CONDITION_MET_EV,
 				     dln2_gpio_event);
 	if (ret) {