Merge tag 'for-5.8/block-2020-06-01' of git://git.kernel.dk/linux-block

[thirdparty/linux.git] / drivers / base / core.c

diff --git a/drivers/base/core.c b/drivers/base/core.c
index fb8ae248e5aa8ec69924d0bea737d45190dd0d6b..de808c5a187b37f9dc2e090e81eadcc3c3591111 100644 (file)
--- 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.
@@ -1374,7 +1393,7 @@ static void device_release(struct kobject *kobj)
        else if (dev->class && dev->class->dev_release)
                dev->class->dev_release(dev);
        else
-               WARN(1, KERN_ERR "Device '%s' does not have a release() function, it is broken and must be fixed. See Documentation/kobject.txt.\n",
+               WARN(1, KERN_ERR "Device '%s' does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst.\n",
                        dev_name(dev));
        kfree(p);
 }
@@ -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);
@@ -3858,6 +3882,7 @@ void set_secondary_fwnode(struct device *dev, struct fwnode_handle *fwnode)
        else
                dev->fwnode = fwnode;
 }
+EXPORT_SYMBOL_GPL(set_secondary_fwnode);
 
 /**
  * device_set_of_node_from_dev - reuse device-tree node of another device