diff --git a/drivers/staging/comedi/drivers/pcl818.c b/drivers/staging/comedi/drivers/pcl818.c
index 0167d7ee6d0d..42448d22ac9f 100644
--- a/drivers/staging/comedi/drivers/pcl818.c
+++ b/drivers/staging/comedi/drivers/pcl818.c
@@ -540,12 +540,41 @@ static int pcl818_do_insn_bits(struct comedi_device *dev,
 	return insn->n;
 }
 
+static bool pcl818_ai_next_chan(struct comedi_device *dev,
+				struct comedi_subdevice *s)
+{
+	struct pcl818_private *devpriv = dev->private;
+	struct comedi_cmd *cmd = &s->async->cmd;
+
+	s->async->events |= COMEDI_CB_BLOCK;
+
+	devpriv->act_chanlist_pos++;
+	if (devpriv->act_chanlist_pos >= devpriv->act_chanlist_len)
+		devpriv->act_chanlist_pos = 0;
+
+	s->async->cur_chan++;
+	if (s->async->cur_chan >= cmd->chanlist_len) {
+		s->async->cur_chan = 0;
+		devpriv->ai_act_scan--;
+		s->async->events |= COMEDI_CB_EOS;
+	}
+
+	if (cmd->stop_src == TRIG_COUNT && devpriv->ai_act_scan == 0) {
+		/* all data sampled */
+		s->cancel(dev, s);
+		s->async->events |= COMEDI_CB_EOA;
+		comedi_event(dev, s);
+		return false;
+	}
+
+	return true;
+}
+
 static irqreturn_t interrupt_pcl818_ai_mode13_int(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;
 	unsigned int chan;
 
 	if (pcl818_ai_eoc(dev, s, NULL, 0)) {
@@ -570,21 +599,10 @@ static irqreturn_t interrupt_pcl818_ai_mode13_int(int irq, void *d)
 		comedi_event(dev, s);
 		return IRQ_HANDLED;
 	}
-	devpriv->act_chanlist_pos++;
-	if (devpriv->act_chanlist_pos >= devpriv->act_chanlist_len)
-		devpriv->act_chanlist_pos = 0;
 
-	s->async->cur_chan++;
-	if (s->async->cur_chan >= cmd->chanlist_len) {
-		s->async->cur_chan = 0;
-		devpriv->ai_act_scan--;
-	}
+	if (!pcl818_ai_next_chan(dev, s))
+		return IRQ_HANDLED;
 
-	if (cmd->stop_src == TRIG_COUNT && devpriv->ai_act_scan == 0) {
-		/* all data sampled */
-		s->cancel(dev, s);
-		s->async->events |= COMEDI_CB_EOA;
-	}
 	comedi_event(dev, s);
 	return IRQ_HANDLED;
 }
@@ -594,7 +612,6 @@ static irqreturn_t interrupt_pcl818_ai_mode13_dma(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;
 	int i, len, bufptr;
 	unsigned short *ptr;
 
@@ -621,23 +638,8 @@ static irqreturn_t interrupt_pcl818_ai_mode13_dma(int irq, void *d)
 
 		comedi_buf_put(s->async, ptr[bufptr++] >> 4);	/*  get one sample */
 
-		devpriv->act_chanlist_pos++;
-		if (devpriv->act_chanlist_pos >= devpriv->act_chanlist_len)
-			devpriv->act_chanlist_pos = 0;
-
-		s->async->cur_chan++;
-		if (s->async->cur_chan >= cmd->chanlist_len) {
-			s->async->cur_chan = 0;
-			devpriv->ai_act_scan--;
-		}
-
-		if (cmd->stop_src == TRIG_COUNT && devpriv->ai_act_scan == 0) {
-			/* all data sampled */
-			s->cancel(dev, s);
-			s->async->events |= COMEDI_CB_EOA;
-			comedi_event(dev, s);
+		if (!pcl818_ai_next_chan(dev, s))
 			return IRQ_HANDLED;
-		}
 	}
 
 	if (len > 0)
@@ -650,7 +652,6 @@ static irqreturn_t interrupt_pcl818_ai_mode13_fifo(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;
 	int i, len;
 	unsigned char lo;
 
@@ -694,23 +695,8 @@ static irqreturn_t interrupt_pcl818_ai_mode13_fifo(int irq, void *d)
 
 		comedi_buf_put(s->async, (lo >> 4) | (inb(dev->iobase + PCL818_FI_DATAHI) << 4));	/*  get one sample */
 
-		devpriv->act_chanlist_pos++;
-		if (devpriv->act_chanlist_pos >= devpriv->act_chanlist_len)
-			devpriv->act_chanlist_pos = 0;
-
-		s->async->cur_chan++;
-		if (s->async->cur_chan >= cmd->chanlist_len) {
-			s->async->cur_chan = 0;
-			devpriv->ai_act_scan--;
-		}
-
-		if (cmd->stop_src == TRIG_COUNT && devpriv->ai_act_scan == 0) {
-			/* all data sampled */
-			s->cancel(dev, s);
-			s->async->events |= COMEDI_CB_EOA;
-			comedi_event(dev, s);
+		if (!pcl818_ai_next_chan(dev, s))
 			return IRQ_HANDLED;
-		}
 	}
 
 	if (len > 0)