diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c
index 3b51055be40e6..7f9334a8af500 100644
--- a/drivers/net/can/dev/dev.c
+++ b/drivers/net/can/dev/dev.c
@@ -530,6 +530,11 @@ int register_candev(struct net_device *dev)
 	if (!priv->data_bitrate_const != !priv->data_bitrate_const_cnt)
 		return -EINVAL;
 
+	/* We only support either fixed bit rates or bit timing const. */
+	if ((priv->bitrate_const || priv->data_bitrate_const) &&
+	    (priv->bittiming_const || priv->data_bittiming_const))
+		return -EINVAL;
+
 	if (!can_bittiming_const_valid(priv->bittiming_const) ||
 	    !can_bittiming_const_valid(priv->data_bittiming_const))
 		return -EINVAL;