diff --git a/drivers/staging/comedi/drivers/addi_apci_1564.c b/drivers/staging/comedi/drivers/addi_apci_1564.c
index 3e8377a3b67b..2664bfa7b8f1 100644
--- a/drivers/staging/comedi/drivers/addi_apci_1564.c
+++ b/drivers/staging/comedi/drivers/addi_apci_1564.c
@@ -87,6 +87,7 @@
 #define APCI1564_DO_INT_STATUS_CC		BIT(1)
 #define APCI1564_DO_INT_STATUS_VCC		BIT(0)
 #define APCI1564_DO_IRQ_REG			0x20
+#define APCI1564_DO_IRQ_INTR			BIT(0)
 #define APCI1564_WDOG_REG			0x24
 #define APCI1564_WDOG_RELOAD_REG		0x28
 #define APCI1564_WDOG_TIMEBASE_REG		0x2c