diff --git a/drivers/staging/comedi/drivers/cb_pcidas64.c b/drivers/staging/comedi/drivers/cb_pcidas64.c
index aa481c00e8e7..942ba5cd8270 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas64.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas64.c
@@ -3251,7 +3251,7 @@ static inline int external_ai_queue_in_use(struct comedi_device *dev)
 {
 	const struct pcidas64_board *board = dev->board_ptr;
 
-	if (dev->read_subdev->busy)
+	if (!dev->read_subdev->busy)
 		return 0;
 	if (board->layout == LAYOUT_4020)
 		return 0;