sh: mach-x3proto: Migrate to linear irq domain.

In the interest of getting off of the create_irq() API we can get all of
the functionality we're interested in through a linear IRQ domain. Fairly
straightforward conversion utilizing a single linear domain.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/boards/Kconfig

@@ -292,6 +292,7 @@ config SH_X3PROTO
 	bool "SH-X3 Prototype board"
 	depends on CPU_SUBTYPE_SHX3
 	select NO_IOPORT if !PCI
+	select IRQ_DOMAIN
 
 config SH_MAGIC_PANEL_R2
 	bool "Magic Panel R2"

arch/sh/boards/mach-x3proto/gpio.c

@@ -3,7 +3,7 @@
  *
  * Renesas SH-X3 Prototype Baseboard GPIO Support.
  *
- * Copyright (C) 2010  Paul Mundt
+ * Copyright (C) 2010 - 2012  Paul Mundt
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
@@ -17,6 +17,7 @@
 #include <linux/irq.h>
 #include <linux/kernel.h>
 #include <linux/spinlock.h>
+#include <linux/irqdomain.h>
 #include <linux/io.h>
 #include <mach/ilsel.h>
 #include <mach/hardware.h>
@@ -26,7 +27,7 @@
 #define KEYDETR 0xb81c0004
 
 static DEFINE_SPINLOCK(x3proto_gpio_lock);
-static unsigned int x3proto_gpio_irq_map[NR_BASEBOARD_GPIOS] = { 0, };
+static struct irq_domain *x3proto_irq_domain;
 
 static int x3proto_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 {
@@ -49,7 +50,14 @@ static int x3proto_gpio_get(struct gpio_chip *chip, unsigned gpio)
 
 static int x3proto_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
 {
-	return x3proto_gpio_irq_map[gpio];
+	int virq;
+
+	if (gpio < chip->ngpio)
+		virq = irq_create_mapping(x3proto_irq_domain, gpio);
+	else
+		virq = -ENXIO;
+
+	return virq;
 }
 
 static void x3proto_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
@@ -62,9 +70,8 @@ static void x3proto_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
 	chip->irq_mask_ack(data);
 
 	mask = __raw_readw(KEYDETR);
-
 	for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS)
-		generic_handle_irq(x3proto_gpio_to_irq(NULL, pin));
+		generic_handle_irq(irq_linear_revmap(x3proto_irq_domain, pin));
 
 	chip->irq_unmask(data);
 }
@@ -78,10 +85,23 @@ struct gpio_chip x3proto_gpio_chip = {
 	.ngpio			= NR_BASEBOARD_GPIOS,
 };
 
+static int x3proto_gpio_irq_map(struct irq_domain *domain, unsigned int virq,
+				irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler_name(virq, &dummy_irq_chip, handle_simple_irq,
+				      "gpio");
+
+	return 0;
+}
+
+static struct irq_domain_ops x3proto_gpio_irq_ops = {
+	.map	= x3proto_gpio_irq_map,
+	.xlate	= irq_domain_xlate_twocell,
+};
+
 int __init x3proto_gpio_setup(void)
 {
-	int ilsel;
-	int ret, i;
+	int ilsel, ret;
 
 	ilsel = ilsel_enable(ILSEL_KEY);
 	if (unlikely(ilsel < 0))
@@ -91,21 +111,10 @@ int __init x3proto_gpio_setup(void)
 	if (unlikely(ret))
 		goto err_gpio;
 
-	for (i = 0; i < NR_BASEBOARD_GPIOS; i++) {
-		unsigned long flags;
-		int irq = create_irq();
-
-		if (unlikely(irq < 0)) {
-			ret = -EINVAL;
+	x3proto_irq_domain = irq_domain_add_linear(NULL, NR_BASEBOARD_GPIOS,
+						   &x3proto_gpio_irq_ops, NULL);
+	if (unlikely(!x3proto_irq_domain))
 		goto err_irq;
-		}
-
-		spin_lock_irqsave(&x3proto_gpio_lock, flags);
-		x3proto_gpio_irq_map[i] = irq;
-		irq_set_chip_and_handler_name(irq, &dummy_irq_chip,
-					      handle_simple_irq, "gpio");
-		spin_unlock_irqrestore(&x3proto_gpio_lock, flags);
-	}
 
 	pr_info("registering '%s' support, handling GPIOs %u -> %u, "
 		"bound to IRQ %u\n",
@@ -119,10 +128,6 @@ int __init x3proto_gpio_setup(void)
 	return 0;
 
 err_irq:
-	for (; i >= 0; --i)
-		if (x3proto_gpio_irq_map[i])
-			destroy_irq(x3proto_gpio_irq_map[i]);
-
 	ret = gpiochip_remove(&x3proto_gpio_chip);
 	if (unlikely(ret))
 		pr_err("Failed deregistering GPIO\n");