diff --git a/drivers/comedi/drivers/pcl818.c b/drivers/comedi/drivers/pcl818.c
index aa775a024fc7..89f32c493caa 100644
--- a/drivers/comedi/drivers/pcl818.c
+++ b/drivers/comedi/drivers/pcl818.c
@@ -534,13 +534,14 @@ static irqreturn_t pcl818_interrupt(int irq, void *d)
 	struct comedi_device *dev = d;
 	struct pcl818_private *devpriv = dev->private;
 	struct comedi_subdevice *s = dev->read_subdev;
-	struct comedi_cmd *cmd = &s->async->cmd;
+	struct comedi_cmd *cmd;
 
 	if (!dev->attached || !devpriv->ai_cmd_running) {
 		pcl818_ai_clear_eoc(dev);
 		return IRQ_HANDLED;
 	}
 
+	cmd = &s->async->cmd;
 	if (devpriv->ai_cmd_canceled) {
 		/*
 		 * The cleanup from ai_cancel() has been delayed