1 files changed, 43 insertions, 19 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 139cdf7e7327..0cad34f1eede 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -365,6 +365,7 @@ struct device_link *device_link_add(struct device *consumer,
 				link->flags |= DL_FLAG_STATELESS;
 				goto reorder;
 			} else {
+				link->flags |= DL_FLAG_STATELESS;
 				goto out;
 			}
 		}
@@ -433,12 +434,16 @@ struct device_link *device_link_add(struct device *consumer,
 	    flags & DL_FLAG_PM_RUNTIME)
 		pm_runtime_resume(supplier);
 
+	list_add_tail_rcu(&link->s_node, &supplier->links.consumers);
+	list_add_tail_rcu(&link->c_node, &consumer->links.suppliers);
+
 	if (flags & DL_FLAG_SYNC_STATE_ONLY) {
 		dev_dbg(consumer,
 			"Linked as a sync state only consumer to %s\n",
 			dev_name(supplier));
 		goto out;
 	}
+
 reorder:
 	/*
 	 * Move the consumer and all of the devices depending on it to the end
@@ -449,12 +454,9 @@ reorder:
 	 */
 	device_reorder_to_tail(consumer, NULL);
 
-	list_add_tail_rcu(&link->s_node, &supplier->links.consumers);
-	list_add_tail_rcu(&link->c_node, &consumer->links.suppliers);
-
 	dev_dbg(consumer, "Linked as a consumer to %s\n", dev_name(supplier));
 
- out:
+out:
 	device_pm_unlock();
 	device_links_write_unlock();
 
@@ -829,6 +831,13 @@ static void __device_links_supplier_defer_sync(struct device *sup)
 		list_add_tail(&sup->links.defer_sync, &deferred_sync);
 }
 
+static void device_link_drop_managed(struct device_link *link)
+{
+	link->flags &= ~DL_FLAG_MANAGED;
+	WRITE_ONCE(link->status, DL_STATE_NONE);
+	kref_put(&link->kref, __device_link_del);
+}
+
 /**
  * device_links_driver_bound - Update device links after probing its driver.
  * @dev: Device to update the links for.
@@ -842,7 +851,7 @@ static void __device_links_supplier_defer_sync(struct device *sup)
  */
 void device_links_driver_bound(struct device *dev)
 {
-	struct device_link *link;
+	struct device_link *link, *ln;
 	LIST_HEAD(sync_list);
 
 	/*
@@ -882,18 +891,35 @@ void device_links_driver_bound(struct device *dev)
 	else
 		__device_links_queue_sync_state(dev, &sync_list);
 
-	list_for_each_entry(link, &dev->links.suppliers, c_node) {
+	list_for_each_entry_safe(link, ln, &dev->links.suppliers, c_node) {
+		struct device *supplier;
+
 		if (!(link->flags & DL_FLAG_MANAGED))
 			continue;
 
-		WARN_ON(link->status != DL_STATE_CONSUMER_PROBE);
-		WRITE_ONCE(link->status, DL_STATE_ACTIVE);
+		supplier = link->supplier;
+		if (link->flags & DL_FLAG_SYNC_STATE_ONLY) {
+			/*
+			 * When DL_FLAG_SYNC_STATE_ONLY is set, it means no
+			 * other DL_MANAGED_LINK_FLAGS have been set. So, it's
+			 * save to drop the managed link completely.
+			 */
+			device_link_drop_managed(link);
+		} else {
+			WARN_ON(link->status != DL_STATE_CONSUMER_PROBE);
+			WRITE_ONCE(link->status, DL_STATE_ACTIVE);
+		}
 
+		/*
+		 * This needs to be done even for the deleted
+		 * DL_FLAG_SYNC_STATE_ONLY device link in case it was the last
+		 * device link that was preventing the supplier from getting a
+		 * sync_state() call.
+		 */
 		if (defer_sync_state_count)
-			__device_links_supplier_defer_sync(link->supplier);
+			__device_links_supplier_defer_sync(supplier);
 		else
-			__device_links_queue_sync_state(link->supplier,
-							&sync_list);
+			__device_links_queue_sync_state(supplier, &sync_list);
 	}
 
 	dev->links.status = DL_DEV_DRIVER_BOUND;
@@ -903,13 +929,6 @@ void device_links_driver_bound(struct device *dev)
 	device_links_flush_sync_list(&sync_list, dev);
 }
 
-static void device_link_drop_managed(struct device_link *link)
-{
-	link->flags &= ~DL_FLAG_MANAGED;
-	WRITE_ONCE(link->status, DL_STATE_NONE);
-	kref_put(&link->kref, __device_link_del);
-}
-
 /**
  * __device_links_no_driver - Update links of a device without a driver.
  * @dev: Device without a drvier.
@@ -2370,6 +2389,11 @@ u32 fw_devlink_get_flags(void)
 	return fw_devlink_flags;
 }
 
+static bool fw_devlink_is_permissive(void)
+{
+	return fw_devlink_flags == DL_FLAG_SYNC_STATE_ONLY;
+}
+
 /**
  * device_add - add device to device hierarchy.
  * @dev: device.
@@ -2524,7 +2548,7 @@ int device_add(struct device *dev)
 	if (fw_devlink_flags && is_fwnode_dev &&
 	    fwnode_has_op(dev->fwnode, add_links)) {
 		fw_ret = fwnode_call_int_op(dev->fwnode, add_links, dev);
-		if (fw_ret == -ENODEV)
+		if (fw_ret == -ENODEV && !fw_devlink_is_permissive())
 			device_link_wait_for_mandatory_supplier(dev);
 		else if (fw_ret)
 			device_link_wait_for_optional_supplier(dev);