+static int lookup_existing_device(struct device *dev, void *data)
+{
+ struct fw_device *old = fw_device(dev);
+ struct fw_device *new = data;
+ struct fw_card *card = new->card;
+ int match = 0;
+
+ down_read(&fw_device_rwsem); /* serialize config_rom access */
+ spin_lock_irq(&card->lock); /* serialize node access */
+
+ if (memcmp(old->config_rom, new->config_rom, 6 * 4) == 0 &&
+ atomic_cmpxchg(&old->state,
+ FW_DEVICE_GONE,
+ FW_DEVICE_RUNNING) == FW_DEVICE_GONE) {
+ struct fw_node *current_node = new->node;
+ struct fw_node *obsolete_node = old->node;
+
+ new->node = obsolete_node;
+ new->node->data = new;
+ old->node = current_node;
+ old->node->data = old;
+
+ old->max_speed = new->max_speed;
+ old->node_id = current_node->node_id;
+ smp_wmb(); /* update node_id before generation */
+ old->generation = card->generation;
+ old->config_rom_retries = 0;
+ fw_notify("rediscovered device %s\n", dev_name(dev));