irqdomain: Implement a method to automatically call parent domains alloc/free

Add a flags to irq_domain.flags to control whether the irqdomain core
should automatically call parent irqdomain's alloc/free callbacks. It
help to reduce hierarchy irqdomains users' code size.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Link: http://lkml.kernel.org/r/1416061447-9472-4-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 7aca1ad..dd2709b 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -134,6 +134,9 @@
 	/* Irq domain is hierarchical */
 	IRQ_DOMAIN_FLAG_HIERARCHY	= (1 << 0),
 
+	/* Core calls alloc/free recursive through the domain hierarchy. */
+	IRQ_DOMAIN_FLAG_AUTO_RECURSIVE	= (1 << 1),
+
 	/*
 	 * Flags starting from IRQ_DOMAIN_FLAG_NONCORE are reserved
 	 * for implementation specific purposes and ignored by the
@@ -285,22 +288,13 @@
 extern void irq_domain_free_irqs_top(struct irq_domain *domain,
 				     unsigned int virq, unsigned int nr_irqs);
 
-static inline int irq_domain_alloc_irqs_parent(struct irq_domain *domain,
-					       unsigned int irq_base,
-					       unsigned int nr_irqs, void *arg)
-{
-	if (domain->parent && domain->parent->ops->alloc)
-		return domain->parent->ops->alloc(domain->parent, irq_base,
-						  nr_irqs, arg);
-	return -ENOSYS;
-}
+extern int irq_domain_alloc_irqs_parent(struct irq_domain *domain,
+					unsigned int irq_base,
+					unsigned int nr_irqs, void *arg);
 
-static inline void irq_domain_free_irqs_parent(struct irq_domain *domain,
-				unsigned int irq_base, unsigned int nr_irqs)
-{
-	if (domain->parent && domain->parent->ops->free)
-		domain->parent->ops->free(domain->parent, irq_base, nr_irqs);
-}
+extern void irq_domain_free_irqs_parent(struct irq_domain *domain,
+					unsigned int irq_base,
+					unsigned int nr_irqs);
 
 static inline bool irq_domain_is_hierarchy(struct irq_domain *domain)
 {