net/mlx4_core: Avoid setting ports to auto when only one port type is…

… supported

When only one port type is supported, it should be read only.
We reject changing requests, even to the auto sense mode.

Fixes: 27bf91d ("mlx4_core: Add link type autosensing")
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/main.c

@@ -1102,6 +1102,14 @@ static int __set_port_type(struct mlx4_port_info *info,
 	int i;
 	int err = 0;
 
+	if ((port_type & mdev->caps.supported_type[info->port]) != port_type) {
+		mlx4_err(mdev,
+			 "Requested port type for port %d is not supported on this HCA\n",
+			 info->port);
+		err = -EINVAL;
+		goto err_sup;
+	}
+
 	mlx4_stop_sense(mdev);
 	mutex_lock(&priv->port_mutex);
 	info->tmp_type = port_type;
@@ -1147,7 +1155,7 @@ static int __set_port_type(struct mlx4_port_info *info,
 out:
 	mlx4_start_sense(mdev);
 	mutex_unlock(&priv->port_mutex);
-
+err_sup:
 	return err;
 }