--- /dev/null
+/* irqreturn.h */
+#ifndef _LINUX_IRQRETURN_H
+#define _LINUX_IRQRETURN_H
+
+/*
+ * For 2.4.x compatibility, 2.4.x can use
+ *
+ * typedef void irqreturn_t;
+ * #define IRQ_NONE
+ * #define IRQ_HANDLED
+ * #define IRQ_RETVAL(x)
+ *
+ * To mix old-style and new-style irq handler returns.
+ *
+ * IRQ_NONE means we didn't handle it.
+ * IRQ_HANDLED means that we did have a valid interrupt and handled it.
+ * IRQ_RETVAL(x) selects on the two depending on x being non-zero (for handled)
+ */
+typedef int irqreturn_t;
+
+#define IRQ_NONE (0)
+#define IRQ_HANDLED (1)
+#define IRQ_RETVAL(x) ((x) != 0)
+
+#endif