ARM: davinci: aintc: use irq domain

We need to create an irq domain if we want to select SPARSE_IRQ. The
cp-intc driver already supports it, but aintc doesn't. Use the helpers
provided by the generic irq chip abstraction.
Reviewed-by: David Lechner <david@lechnology.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

arch/arm/mach-davinci/irq.c

@@ -23,6 +23,7 @@
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/io.h>
+#include <linux/irqdomain.h>
 
 #include <mach/hardware.h>
 #include <mach/cputype.h>
@@ -40,23 +41,23 @@
 #define IRQ_INTPRI0_REG_OFFSET	0x0030
 #define IRQ_INTPRI7_REG_OFFSET	0x004C
 
+static struct irq_domain *davinci_irq_domain;
+
 static inline void davinci_irq_writel(unsigned long value, int offset)
 {
 	__raw_writel(value, davinci_intc_base + offset);
 }
 
 static __init void
-davinci_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
+davinci_irq_setup_gc(void __iomem *base,
+		     unsigned int irq_start, unsigned int num)
 {
 	struct irq_chip_generic *gc;
 	struct irq_chip_type *ct;
 
-	gc = irq_alloc_generic_chip("AINTC", 1, irq_start, base, handle_edge_irq);
-	if (!gc) {
-		pr_err("%s: irq_alloc_generic_chip for IRQ %u failed\n",
-		       __func__, irq_start);
-		return;
-	}
+	gc = irq_get_domain_generic_chip(davinci_irq_domain, irq_start);
+	gc->reg_base = base;
+	gc->irq_base = irq_start;
 
 	ct = gc->chip_types;
 	ct->chip.irq_ack = irq_gc_ack_set_bit;
@@ -74,6 +75,7 @@ void __init davinci_irq_init(void)
 {
 	unsigned i, j;
 	const u8 *davinci_def_priorities = davinci_soc_info.intc_irq_prios;
+	int ret, irq_base;
 
 	davinci_intc_type = DAVINCI_INTC_TYPE_AINTC;
 	davinci_intc_base = ioremap(davinci_soc_info.intc_base, SZ_4K);
@@ -110,8 +112,25 @@ void __init davinci_irq_init(void)
 		davinci_irq_writel(pri, i);
 	}
 
+	irq_base = irq_alloc_descs(-1, 0, davinci_soc_info.intc_irq_num, 0);
+	if (WARN_ON(irq_base < 0))
+		return;
+
+	davinci_irq_domain = irq_domain_add_legacy(NULL,
+					davinci_soc_info.intc_irq_num,
+					irq_base, 0, &irq_domain_simple_ops,
+					NULL);
+	if (WARN_ON(!davinci_irq_domain))
+		return;
+
+	ret = irq_alloc_domain_generic_chips(davinci_irq_domain, 32, 1,
+					    "AINTC", handle_edge_irq,
+					    IRQ_NOREQUEST | IRQ_NOPROBE, 0, 0);
+	if (WARN_ON(ret))
+		return;
+
 	for (i = 0, j = 0; i < davinci_soc_info.intc_irq_num; i += 32, j += 0x04)
-		davinci_alloc_gc(davinci_intc_base + j, i, 32);
+		davinci_irq_setup_gc(davinci_intc_base + j, irq_base + i, 32);
 
 	irq_set_handler(IRQ_TINT1_TINT34, handle_level_irq);
 }