pinctrl: mcp23s08: 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_nested() and
gpiochip_set_nested_irqchip(). The irqchip is instead
added while adding the gpiochip.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Lars Poeschel <poeschel@lemonage.de>
Cc: Jason Kridner <jkridner@gmail.com>
Link: https://lore.kernel.org/r/20200721125223.344411-1-linus.walleij@linaro.org

drivers/pinctrl/pinctrl-mcp23s08.c

@@ -522,29 +522,6 @@ static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
 	return 0;
 }
 
-static int mcp23s08_irqchip_setup(struct mcp23s08 *mcp)
-{
-	struct gpio_chip *chip = &mcp->chip;
-	int err;
-
-	err =  gpiochip_irqchip_add_nested(chip,
-					   &mcp->irq_chip,
-					   0,
-					   handle_simple_irq,
-					   IRQ_TYPE_NONE);
-	if (err) {
-		dev_err(chip->parent,
-			"could not connect irqchip to gpiochip: %d\n", err);
-		return err;
-	}
-
-	gpiochip_set_nested_irqchip(chip,
-				    &mcp->irq_chip,
-				    mcp->irq);
-
-	return 0;
-}
-
 /*----------------------------------------------------------------------*/
 
 int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
@@ -589,10 +566,6 @@ int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 	if (ret < 0)
 		goto fail;
 
-	ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
-	if (ret < 0)
-		goto fail;
-
 	mcp->irq_controller =
 		device_property_read_bool(dev, "interrupt-controller");
 	if (mcp->irq && mcp->irq_controller) {
@@ -629,11 +602,22 @@ int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
 	}
 
 	if (mcp->irq && mcp->irq_controller) {
-		ret = mcp23s08_irqchip_setup(mcp);
-		if (ret)
-			goto fail;
+		struct gpio_irq_chip *girq = &mcp->chip.irq;
+
+		girq->chip = &mcp->irq_chip;
+		/* This will let us handle the parent IRQ in the driver */
+		girq->parent_handler = NULL;
+		girq->num_parents = 0;
+		girq->parents = NULL;
+		girq->default_type = IRQ_TYPE_NONE;
+		girq->handler = handle_simple_irq;
+		girq->threaded = true;
 	}
 
+	ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
+	if (ret < 0)
+		goto fail;
+
 	mcp->pinctrl_desc.pctlops = &mcp_pinctrl_ops;
 	mcp->pinctrl_desc.confops = &mcp_pinconf_ops;
 	mcp->pinctrl_desc.npins = mcp->chip.ngpio;