static inline int gpio_dw_set_callback(struct device *port,
- gpio_callback_t callback)
+ gpio_callback_t callback,

When I say it's untested, it's for real ... should be *callback here.

/**
@@ -310,7 +336,6 @@ static inline int gpio_port_enable_callback(struct device *port)

api = (struct gpio_driver_api *) port->driver_api;
return api->enable_callback(port, GPIO_ACCESS_BY_PORT, 0);
-
}

With new api, this would call all callback handles, whatever is their
pin_mask.
(see _gpio_fire_callbacks())