return NULL;
 }
 
+/* Compare two async sub-device descriptors for equivalence */
+static bool asd_equal(struct v4l2_async_subdev *asd_x,
+                     struct v4l2_async_subdev *asd_y)
+{
+       if (asd_x->match_type != asd_y->match_type)
+               return false;
+
+       switch (asd_x->match_type) {
+       case V4L2_ASYNC_MATCH_DEVNAME:
+               return strcmp(asd_x->match.device_name,
+                             asd_y->match.device_name) == 0;
+       case V4L2_ASYNC_MATCH_I2C:
+               return asd_x->match.i2c.adapter_id ==
+                       asd_y->match.i2c.adapter_id &&
+                       asd_x->match.i2c.address ==
+                       asd_y->match.i2c.address;
+       case V4L2_ASYNC_MATCH_FWNODE:
+               return asd_x->match.fwnode == asd_y->match.fwnode;
+       default:
+               break;
+       }
+
+       return false;
+}
+
 /* Find the sub-device notifier registered by a sub-device driver. */
 static struct v4l2_async_notifier *v4l2_async_find_subdev_notifier(
        struct v4l2_subdev *sd)
        notifier->parent = NULL;
 }
 
-/* See if an fwnode can be found in a notifier's lists. */
-static bool __v4l2_async_notifier_fwnode_has_async_subdev(
-       struct v4l2_async_notifier *notifier, struct fwnode_handle *fwnode)
+/* See if an async sub-device can be found in a notifier's lists. */
+static bool
+__v4l2_async_notifier_has_async_subdev(struct v4l2_async_notifier *notifier,
+                                      struct v4l2_async_subdev *asd)
 {
-       struct v4l2_async_subdev *asd;
+       struct v4l2_async_subdev *asd_y;
        struct v4l2_subdev *sd;
 
-       list_for_each_entry(asd, ¬ifier->waiting, list) {
-               if (asd->match_type != V4L2_ASYNC_MATCH_FWNODE)
-                       continue;
-
-               if (asd->match.fwnode == fwnode)
+       list_for_each_entry(asd_y, ¬ifier->waiting, list)
+               if (asd_equal(asd, asd_y))
                        return true;
-       }
 
        list_for_each_entry(sd, ¬ifier->done, async_list) {
                if (WARN_ON(!sd->asd))
                        continue;
 
-               if (sd->asd->match_type != V4L2_ASYNC_MATCH_FWNODE)
-                       continue;
-
-               if (sd->asd->match.fwnode == fwnode)
+               if (asd_equal(asd, sd->asd))
                        return true;
        }
 
 }
 
 /*
- * Find out whether an async sub-device was set up for an fwnode already or
+ * Find out whether an async sub-device was set up already or
  * whether it exists in a given notifier before @this_index.
  */
-static bool v4l2_async_notifier_fwnode_has_async_subdev(
-       struct v4l2_async_notifier *notifier, struct fwnode_handle *fwnode,
-       unsigned int this_index)
+static bool
+v4l2_async_notifier_has_async_subdev(struct v4l2_async_notifier *notifier,
+                                    struct v4l2_async_subdev *asd,
+                                    unsigned int this_index)
 {
        unsigned int j;
 
        lockdep_assert_held(&list_lock);
 
-       /* Check that an fwnode is not being added more than once. */
+       /* Check that an asd is not being added more than once. */
        for (j = 0; j < this_index; j++) {
-               struct v4l2_async_subdev *asd = notifier->subdevs[this_index];
-               struct v4l2_async_subdev *other_asd = notifier->subdevs[j];
+               struct v4l2_async_subdev *asd_y = notifier->subdevs[j];
 
-               if (other_asd->match_type == V4L2_ASYNC_MATCH_FWNODE &&
-                   asd->match.fwnode ==
-                   other_asd->match.fwnode)
+               if (asd_equal(asd, asd_y))
                        return true;
        }
 
-       /* Check than an fwnode did not exist in other notifiers. */
+       /* Check that an asd does not exist in other notifiers. */
        list_for_each_entry(notifier, ¬ifier_list, list)
-               if (__v4l2_async_notifier_fwnode_has_async_subdev(
-                           notifier, fwnode))
+               if (__v4l2_async_notifier_has_async_subdev(notifier, asd))
                        return true;
 
        return false;
                case V4L2_ASYNC_MATCH_CUSTOM:
                case V4L2_ASYNC_MATCH_DEVNAME:
                case V4L2_ASYNC_MATCH_I2C:
-                       break;
                case V4L2_ASYNC_MATCH_FWNODE:
-                       if (v4l2_async_notifier_fwnode_has_async_subdev(
-                                   notifier, asd->match.fwnode, i)) {
+                       if (v4l2_async_notifier_has_async_subdev(notifier,
+                                                                asd, i)) {
                                dev_err(dev,
-                                       "fwnode has already been registered or in notifier's subdev list\n");
+                                       "subdev descriptor already listed in this or other notifiers\n");
                                ret = -EEXIST;
                                goto err_unlock;
                        }