In case when the properties are supplied in the secondary fwnode
(for example, built-in device properties) the fwnode pointer left
unassigned. This makes unable to retrieve them.
Assign fwnode to parent's if no primary one provided.
Fixes: 7cba1a4d5e16 ("gpiolib: generalize devprop_gpiochip_set_names() for device properties")
Fixes: 2afa97e9868f ("gpiolib: Read "gpio-line-names" from a firmware node")
Reported-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Tested-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
                               struct lock_class_key *lock_key,
                               struct lock_class_key *request_key)
 {
+       struct fwnode_handle *fwnode = gc->parent ? dev_fwnode(gc->parent) : NULL;
        unsigned long   flags;
        int             ret = 0;
        unsigned        i;
 
        of_gpio_dev_init(gc, gdev);
 
+       /*
+        * Assign fwnode depending on the result of the previous calls,
+        * if none of them succeed, assign it to the parent's one.
+        */
+       gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode;
+
        gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
        if (gdev->id < 0) {
                ret = gdev->id;