gpio/mxs: adopt irq_domain support for mxs gpio driver

Remove irq_domain_add_legacy call from mach-mxs.c and have the gpio
driver adopt irqdomain support, so that we can have the mapping
between gpio and irq number available without using virtual_irq_start
and MXS_GPIO_IRQ_START.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/arch/arm/mach-mxs/mach-mxs.c b/arch/arm/mach-mxs/mach-mxs.c
index 8dabfe8..78bf07a 100644
--- a/arch/arm/mach-mxs/mach-mxs.c
+++ b/arch/arm/mach-mxs/mach-mxs.c
@@ -113,20 +113,8 @@
 	return 0;
 }
 
-static int __init mxs_gpio_add_irq_domain(struct device_node *np,
-				struct device_node *interrupt_parent)
-{
-	static int gpio_irq_base = MXS_GPIO_IRQ_START;
-
-	irq_domain_add_legacy(np, 32, gpio_irq_base, 0, &irq_domain_simple_ops, NULL);
-	gpio_irq_base += 32;
-
-	return 0;
-}
-
 static const struct of_device_id mxs_irq_match[] __initconst = {
 	{ .compatible = "fsl,mxs-icoll", .data = mxs_icoll_add_irq_domain, },
-	{ .compatible = "fsl,mxs-gpio", .data = mxs_gpio_add_irq_domain, },
 	{ /* sentinel */ }
 };
 
diff --git a/drivers/gpio/gpio-mxs.c b/drivers/gpio/gpio-mxs.c
index 39e4956..796fb13 100644
--- a/drivers/gpio/gpio-mxs.c
+++ b/drivers/gpio/gpio-mxs.c
@@ -24,6 +24,7 @@
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/gpio.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
@@ -52,8 +53,6 @@
 #define GPIO_INT_LEV_MASK	(1 << 0)
 #define GPIO_INT_POL_MASK	(1 << 1)
 
-#define irq_to_gpio(irq)	((irq) - MXS_GPIO_IRQ_START)
-
 enum mxs_gpio_id {
 	IMX23_GPIO,
 	IMX28_GPIO,
@@ -63,7 +62,7 @@
 	void __iomem *base;
 	int id;
 	int irq;
-	int virtual_irq_start;
+	struct irq_domain *domain;
 	struct bgpio_chip bgc;
 	enum mxs_gpio_id devid;
 };
@@ -82,8 +81,7 @@
 
 static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type)
 {
-	u32 gpio = irq_to_gpio(d->irq);
-	u32 pin_mask = 1 << (gpio & 31);
+	u32 pin_mask = 1 << d->hwirq;
 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 	struct mxs_gpio_port *port = gc->private;
 	void __iomem *pin_addr;
@@ -120,7 +118,7 @@
 	else
 		writel(pin_mask, pin_addr + MXS_CLR);
 
-	writel(1 << (gpio & 0x1f),
+	writel(pin_mask,
 	       port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
 
 	return 0;
@@ -131,7 +129,6 @@
 {
 	u32 irq_stat;
 	struct mxs_gpio_port *port = irq_get_handler_data(irq);
-	u32 gpio_irq_no_base = port->virtual_irq_start;
 
 	desc->irq_data.chip->irq_ack(&desc->irq_data);
 
@@ -140,7 +137,7 @@
 
 	while (irq_stat != 0) {
 		int irqoffset = fls(irq_stat) - 1;
-		generic_handle_irq(gpio_irq_no_base + irqoffset);
+		generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
 		irq_stat &= ~(1 << irqoffset);
 	}
 }
@@ -167,12 +164,12 @@
 	return 0;
 }
 
-static void __init mxs_gpio_init_gc(struct mxs_gpio_port *port)
+static void __init mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base)
 {
 	struct irq_chip_generic *gc;
 	struct irq_chip_type *ct;
 
-	gc = irq_alloc_generic_chip("gpio-mxs", 1, port->virtual_irq_start,
+	gc = irq_alloc_generic_chip("gpio-mxs", 1, irq_base,
 				    port->base, handle_level_irq);
 	gc->private = port;
 
@@ -194,7 +191,7 @@
 	struct mxs_gpio_port *port =
 		container_of(bgc, struct mxs_gpio_port, bgc);
 
-	return port->virtual_irq_start + offset;
+	return irq_find_mapping(port->domain, offset);
 }
 
 static struct platform_device_id mxs_gpio_ids[] = {
@@ -226,6 +223,7 @@
 	static void __iomem *base;
 	struct mxs_gpio_port *port;
 	struct resource *iores = NULL;
+	int irq_base;
 	int err;
 
 	port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL);
@@ -241,7 +239,6 @@
 		port->id = pdev->id;
 		port->devid = pdev->id_entry->driver_data;
 	}
-	port->virtual_irq_start = MXS_GPIO_IRQ_START + port->id * 32;
 
 	port->irq = platform_get_irq(pdev, 0);
 	if (port->irq < 0)
@@ -275,8 +272,19 @@
 	/* clear address has to be used to clear IRQSTAT bits */
 	writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR);
 
+	irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id());
+	if (irq_base < 0)
+		return irq_base;
+
+	port->domain = irq_domain_add_legacy(np, 32, irq_base, 0,
+					     &irq_domain_simple_ops, NULL);
+	if (!port->domain) {
+		err = -ENODEV;
+		goto out_irqdesc_free;
+	}
+
 	/* gpio-mxs can be a generic irq chip */
-	mxs_gpio_init_gc(port);
+	mxs_gpio_init_gc(port, irq_base);
 
 	/* setup one handler for each entry */
 	irq_set_chained_handler(port->irq, mxs_gpio_irq_handler);
@@ -287,18 +295,22 @@
 			 port->base + PINCTRL_DOUT(port), NULL,
 			 port->base + PINCTRL_DOE(port), NULL, 0);
 	if (err)
-		return err;
+		goto out_irqdesc_free;
 
 	port->bgc.gc.to_irq = mxs_gpio_to_irq;
 	port->bgc.gc.base = port->id * 32;
 
 	err = gpiochip_add(&port->bgc.gc);
-	if (err) {
-		bgpio_remove(&port->bgc);
-		return err;
-	}
+	if (err)
+		goto out_bgpio_remove;
 
 	return 0;
+
+out_bgpio_remove:
+	bgpio_remove(&port->bgc);
+out_irqdesc_free:
+	irq_free_descs(irq_base, 32);
+	return err;
 }
 
 static struct platform_driver mxs_gpio_driver = {