diff --git a/drivers/staging/comedi/drivers/pcm_common.c b/drivers/staging/comedi/drivers/pcm_common.c
index 85ee05ece9c8cc8e7605910e80e695929874bb9b..8a718aea6f3c56bd9d6fea30cb9b11d3180695cf 100644
--- a/drivers/staging/comedi/drivers/pcm_common.c
+++ b/drivers/staging/comedi/drivers/pcm_common.c
@@ -29,41 +29,19 @@ int comedi_pcm_cmdtest(struct comedi_device *dev,
 	if (err)
 		return 2;
 
-	/* step 3: make sure arguments are trivially compatible */
+	/* Step 3: check if arguments are trivially valid */
 
-	/* cmd->start_src == TRIG_NOW || cmd->start_src == TRIG_INT */
-	if (cmd->start_arg != 0) {
-		cmd->start_arg = 0;
-		err++;
-	}
-
-	/* cmd->scan_begin_src == TRIG_EXT */
-	if (cmd->scan_begin_arg != 0) {
-		cmd->scan_begin_arg = 0;
-		err++;
-	}
-
-	/* cmd->convert_src == TRIG_NOW */
-	if (cmd->convert_arg != 0) {
-		cmd->convert_arg = 0;
-		err++;
-	}
-
-	/* cmd->scan_end_src == TRIG_COUNT */
-	if (cmd->scan_end_arg != cmd->chanlist_len) {
-		cmd->scan_end_arg = cmd->chanlist_len;
-		err++;
-	}
+	err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
+	err |= cfc_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
+	err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0);
+	err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
 
 	switch (cmd->stop_src) {
 	case TRIG_COUNT:
 		/* any count allowed */
 		break;
 	case TRIG_NONE:
-		if (cmd->stop_arg != 0) {
-			cmd->stop_arg = 0;
-			err++;
-		}
+		err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
 		break;
 	default:
 		break;