diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index e70ed55..1b5d742 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -44,6 +44,19 @@
 
 extern void irq_set_thread_affinity(struct irq_desc *desc);
 
+/* Inline functions for support of irq chips on slow busses */
+static inline void chip_bus_lock(unsigned int irq, struct irq_desc *desc)
+{
+	if (unlikely(desc->chip->bus_lock))
+		desc->chip->bus_lock(irq);
+}
+
+static inline void chip_bus_sync_unlock(unsigned int irq, struct irq_desc *desc)
+{
+	if (unlikely(desc->chip->bus_sync_unlock))
+		desc->chip->bus_sync_unlock(irq);
+}
+
 /*
  * Debugging printout:
  */