Checking for NULL is incorrect as serial_base_ctrl_add() uses ERR_PTR().
Let's also pass any returned error along, there's no reason to translate
all errors to -ENODEV.
Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230602070007.59268-1-tony@atomide.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
        ctrl_dev = serial_core_ctrl_find(drv, port->dev, port->ctrl_id);
        if (!ctrl_dev) {
                new_ctrl_dev = serial_core_ctrl_device_add(port);
-               if (!new_ctrl_dev) {
-                       ret = -ENODEV;
+               if (IS_ERR(new_ctrl_dev)) {
+                       ret = PTR_ERR(new_ctrl_dev);
                        goto err_unlock;
                }
                ctrl_dev = new_ctrl_dev;