diff --git a/drivers/staging/comedi/drivers/usbdux.c b/drivers/staging/comedi/drivers/usbdux.c
index 8eb2742e6fef..5adbfedf780f 100644
--- a/drivers/staging/comedi/drivers/usbdux.c
+++ b/drivers/staging/comedi/drivers/usbdux.c
@@ -623,12 +623,10 @@ static int usbdux_ai_cmdtest(struct comedi_device *dev,
 
 	err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
 
-	if (cmd->stop_src == TRIG_COUNT) {
-		/* any count is allowed */
-	} else {
-		/* TRIG_NONE */
+	if (cmd->stop_src == TRIG_COUNT)
+		err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1);
+	else	/* TRIG_NONE */
 		err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
-	}
 
 	if (err)
 		return 3;
@@ -1003,12 +1001,10 @@ static int usbdux_ao_cmdtest(struct comedi_device *dev,
 
 	err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
 
-	if (cmd->stop_src == TRIG_COUNT) {
-		/* any count is allowed */
-	} else {
-		/* TRIG_NONE */
+	if (cmd->stop_src == TRIG_COUNT)
+		err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1);
+	else	/* TRIG_NONE */
 		err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
-	}
 
 	if (err)
 		return 3;