irq/generic-chip: Export irq_init_generic_chip() locally

This function will be used in the devres variant of
irq_alloc_generic_chip().

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-doc@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Link: http://lkml.kernel.org/r/1496246820-13250-4-git-send-email-brgl@bgdev.pl

kernel/irq/generic-chip.c

@@ -201,10 +201,9 @@ static void irq_writel_be(u32 val, void __iomem *addr)
 	iowrite32be(val, addr);
 }
 
-static void
-irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
-		      int num_ct, unsigned int irq_base,
-		      void __iomem *reg_base, irq_flow_handler_t handler)
+void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
+			   int num_ct, unsigned int irq_base,
+			   void __iomem *reg_base, irq_flow_handler_t handler)
 {
 	raw_spin_lock_init(&gc->lock);
 	gc->num_ct = num_ct;

kernel/irq/internals.h

@@ -226,3 +226,14 @@ irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { }
 static inline void
 irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action) { }
 #endif
+
+#ifdef CONFIG_GENERIC_IRQ_CHIP
+void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
+			   int num_ct, unsigned int irq_base,
+			   void __iomem *reg_base, irq_flow_handler_t handler);
+#else
+static inline void
+irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
+		      int num_ct, unsigned int irq_base,
+		      void __iomem *reg_base, irq_flow_handler_t handler) { }
+#endif /* CONFIG_GENERIC_IRQ_CHIP */