diff --git a/include/linux/irq.h b/include/linux/irq.h
index 2110f46fcafa..8ff71d14365a 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -637,6 +637,10 @@ int arch_setup_hwirq(unsigned int irq, int node);
 void arch_teardown_hwirq(unsigned int irq);
 #endif
 
+#ifdef CONFIG_GENERIC_IRQ_LEGACY
+void irq_init_desc(unsigned int irq);
+#endif
+
 #ifndef irq_reg_writel
 # define irq_reg_writel(val, addr)	writel(val, addr)
 #endif
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index a83f10e406c1..d269cecdfbf0 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -5,6 +5,10 @@ menu "IRQ subsystem"
 config MAY_HAVE_SPARSE_IRQ
        bool
 
+# Legacy support, required for itanic
+config GENERIC_IRQ_LEGACY
+       bool
+
 # Enable the generic irq autoprobe mechanism
 config GENERIC_IRQ_PROBE
 	bool
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index d514ed6080e1..7f267799a717 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -306,6 +306,13 @@ void irq_mark_irq(unsigned int irq)
 	mutex_unlock(&sparse_irq_lock);
 }
 
+#ifdef CONFIG_GENERIC_IRQ_LEGACY
+void irq_init_desc(unsigned int irq)
+{
+	dynamic_irq_cleanup(irq);
+}
+#endif
+
 #endif /* !CONFIG_SPARSE_IRQ */
 
 /**