Merge tag 'driver-core-5.11-rc1' of...

Merge tag 'driver-core-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the big driver core updates for 5.11-rc1

  This time there was a lot of different work happening here for some
  reason:

   - redo of the fwnode link logic, speeding it up greatly

   - auxiliary bus added (this was a tag that will be pulled in from
     other trees/maintainers this merge window as well, as driver
     subsystems started to rely on it)

   - platform driver core cleanups on the way to fixing some long-time
     api updates in future releases

   - minor fixes and tweaks.

  All have been in linux-next with no (finally) reported issues. Testing
  there did helped in shaking issues out a lot :)"

* tag 'driver-core-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (39 commits)
  driver core: platform: don't oops in platform_shutdown() on unbound devices
  ACPI: Use fwnode_init() to set up fwnode
  misc: pvpanic: Replace OF headers by mod_devicetable.h
  misc: pvpanic: Combine ACPI and platform drivers
  usb: host: sl811: Switch to use platform_get_mem_or_io()
  vfio: platform: Switch to use platform_get_mem_or_io()
  driver core: platform: Introduce platform_get_mem_or_io()
  dyndbg: fix use before null check
  soc: fix comment for freeing soc_dev_attr
  driver core: platform: use bus_type functions
  driver core: platform: change logic implementing platform_driver_probe
  driver core: platform: reorder functions
  driver core: make driver_probe_device() static
  driver core: Fix a couple of typos
  driver core: Reorder devices on successful probe
  driver core: Delete pointless parameter in fwnode_operations.add_links
  driver core: Refactor fw_devlink feature
  efi: Update implementation of add_links() to create fwnode links
  of: property: Update implementation of add_links() to create fwnode links
  driver core: Use device's fwnode to check if it is waiting for suppliers
  ...

drivers/acpi/property.c

@@ -76,7 +76,7 @@ static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
 		return false;
 
 	dn->name = link->package.elements[0].string.pointer;
-	dn->fwnode.ops = &acpi_data_fwnode_ops;
+	fwnode_init(&dn->fwnode, &acpi_data_fwnode_ops);
 	dn->parent = parent;
 	INIT_LIST_HEAD(&dn->data.properties);
 	INIT_LIST_HEAD(&dn->data.subnodes);

drivers/acpi/scan.c

@@ -1589,7 +1589,7 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
 	device->device_type = type;
 	device->handle = handle;
 	device->parent = acpi_bus_get_parent(handle);
-	device->fwnode.ops = &acpi_device_fwnode_ops;
+	fwnode_init(&device->fwnode, &acpi_device_fwnode_ops);
 	acpi_set_device_status(device, sta);
 	acpi_device_get_busid(device);
 	acpi_set_pnp_ids(handle, &device->pnp, type);

drivers/base/auxiliary.c

@@ -92,10 +92,15 @@ static int auxiliary_bus_remove(struct device *dev)
 
 static void auxiliary_bus_shutdown(struct device *dev)
 {
-	struct auxiliary_driver *auxdrv = to_auxiliary_drv(dev->driver);
-	struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
+	struct auxiliary_driver *auxdrv = NULL;
+	struct auxiliary_device *auxdev;
+
+	if (dev->driver) {
+		auxdrv = to_auxiliary_drv(dev->driver);
+		auxdev = to_auxiliary_dev(dev);
+	}
 
-	if (auxdrv->shutdown)
+	if (auxdrv && auxdrv->shutdown)
 		auxdrv->shutdown(auxdev);
 }
 

drivers/base/base.h

@@ -133,7 +133,6 @@ extern void device_release_driver_internal(struct device *dev,
 					   struct device *parent);
 
 extern void driver_detach(struct device_driver *drv);
-extern int driver_probe_device(struct device_driver *drv, struct device *dev);
 extern void driver_deferred_probe_del(struct device *dev);
 extern void device_set_deferred_probe_reason(const struct device *dev,
 					     struct va_format *vaf);

drivers/base/class.c

@@ -210,7 +210,7 @@ static void class_create_release(struct class *cls)
 }
 
 /**
- * class_create - create a struct class structure
+ * __class_create - create a struct class structure
  * @owner: pointer to the module that is to "own" this struct class
  * @name: pointer to a string for the name of this class.
  * @key: the lock_class_key for this class; used by mutex lock debugging

drivers/base/core.c

@@ -46,15 +46,108 @@ early_param("sysfs.deprecated", sysfs_deprecated_setup);
 #endif
 
 /* Device links support. */
-static LIST_HEAD(wait_for_suppliers);
-static DEFINE_MUTEX(wfs_lock);
 static LIST_HEAD(deferred_sync);
 static unsigned int defer_sync_state_count = 1;
-static unsigned int defer_fw_devlink_count;
-static LIST_HEAD(deferred_fw_devlink);
-static DEFINE_MUTEX(defer_fw_devlink_lock);
+static DEFINE_MUTEX(fwnode_link_lock);
 static bool fw_devlink_is_permissive(void);
 
+/**
+ * fwnode_link_add - Create a link between two fwnode_handles.
+ * @con: Consumer end of the link.
+ * @sup: Supplier end of the link.
+ *
+ * Create a fwnode link between fwnode handles @con and @sup. The fwnode link
+ * represents the detail that the firmware lists @sup fwnode as supplying a
+ * resource to @con.
+ *
+ * The driver core will use the fwnode link to create a device link between the
+ * two device objects corresponding to @con and @sup when they are created. The
+ * driver core will automatically delete the fwnode link between @con and @sup
+ * after doing that.
+ *
+ * Attempts to create duplicate links between the same pair of fwnode handles
+ * are ignored and there is no reference counting.
+ */
+int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup)
+{
+	struct fwnode_link *link;
+	int ret = 0;
+
+	mutex_lock(&fwnode_link_lock);
+
+	list_for_each_entry(link, &sup->consumers, s_hook)
+		if (link->consumer == con)
+			goto out;
+
+	link = kzalloc(sizeof(*link), GFP_KERNEL);
+	if (!link) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	link->supplier = sup;
+	INIT_LIST_HEAD(&link->s_hook);
+	link->consumer = con;
+	INIT_LIST_HEAD(&link->c_hook);
+
+	list_add(&link->s_hook, &sup->consumers);
+	list_add(&link->c_hook, &con->suppliers);
+out:
+	mutex_unlock(&fwnode_link_lock);
+
+	return ret;
+}
+
+/**
+ * fwnode_links_purge_suppliers - Delete all supplier links of fwnode_handle.
+ * @fwnode: fwnode whose supplier links need to be deleted
+ *
+ * Deletes all supplier links connecting directly to @fwnode.
+ */
+static void fwnode_links_purge_suppliers(struct fwnode_handle *fwnode)
+{
+	struct fwnode_link *link, *tmp;
+
+	mutex_lock(&fwnode_link_lock);
+	list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) {
+		list_del(&link->s_hook);
+		list_del(&link->c_hook);
+		kfree(link);
+	}
+	mutex_unlock(&fwnode_link_lock);
+}
+
+/**
+ * fwnode_links_purge_consumers - Delete all consumer links of fwnode_handle.
+ * @fwnode: fwnode whose consumer links need to be deleted
+ *
+ * Deletes all consumer links connecting directly to @fwnode.
+ */
+static void fwnode_links_purge_consumers(struct fwnode_handle *fwnode)
+{
+	struct fwnode_link *link, *tmp;
+
+	mutex_lock(&fwnode_link_lock);
+	list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) {
+		list_del(&link->s_hook);
+		list_del(&link->c_hook);
+		kfree(link);
+	}
+	mutex_unlock(&fwnode_link_lock);
+}
+
+/**
+ * fwnode_links_purge - Delete all links connected to a fwnode_handle.
+ * @fwnode: fwnode whose links needs to be deleted
+ *
+ * Deletes all links connecting directly to a fwnode.
+ */
+void fwnode_links_purge(struct fwnode_handle *fwnode)
+{
+	fwnode_links_purge_suppliers(fwnode);
+	fwnode_links_purge_consumers(fwnode);
+}
+
 #ifdef CONFIG_SRCU
 static DEFINE_MUTEX(device_links_lock);
 DEFINE_STATIC_SRCU(device_links_srcu);
@@ -468,7 +561,7 @@ postcore_initcall(devlink_class_init);
  * with runtime PM.  First, setting the DL_FLAG_PM_RUNTIME flag will cause the
  * runtime PM framework to take the link into account.  Second, if the
  * DL_FLAG_RPM_ACTIVE flag is set in addition to it, the supplier devices will
- * be forced into the active metastate and reference-counted upon the creation
+ * be forced into the active meta state and reference-counted upon the creation
  * of the link.  If DL_FLAG_PM_RUNTIME is not set, DL_FLAG_RPM_ACTIVE will be
  * ignored.
  *
@@ -491,7 +584,7 @@ postcore_initcall(devlink_class_init);
  * Also, if DL_FLAG_STATELESS, DL_FLAG_AUTOREMOVE_CONSUMER and
  * DL_FLAG_AUTOREMOVE_SUPPLIER are not set in @flags (that is, a persistent
  * managed device link is being added), the DL_FLAG_AUTOPROBE_CONSUMER flag can
- * be used to request the driver core to automaticall probe for a consmer
+ * be used to request the driver core to automatically probe for a consumer
  * driver after successfully binding a driver to the supplier device.
  *
  * The combination of DL_FLAG_STATELESS and one of DL_FLAG_AUTOREMOVE_CONSUMER,
@@ -555,6 +648,17 @@ struct device_link *device_link_add(struct device *consumer,
 		goto out;
 	}
 
+	/*
+	 * SYNC_STATE_ONLY links are useless once a consumer device has probed.
+	 * So, only create it if the consumer hasn't probed yet.
+	 */
+	if (flags & DL_FLAG_SYNC_STATE_ONLY &&
+	    consumer->links.status != DL_DEV_NO_DRIVER &&
+	    consumer->links.status != DL_DEV_PROBING) {
+		link = NULL;
+		goto out;
+	}
+
 	/*
 	 * DL_FLAG_AUTOREMOVE_SUPPLIER indicates that the link will be needed
 	 * longer than for DL_FLAG_AUTOREMOVE_CONSUMER and setting them both
@@ -697,74 +801,6 @@ struct device_link *device_link_add(struct device *consumer,
 }
 EXPORT_SYMBOL_GPL(device_link_add);
 
-/**
- * device_link_wait_for_supplier - Add device to wait_for_suppliers list
- * @consumer: Consumer device
- *
- * Marks the @consumer device as waiting for suppliers to become available by
- * adding it to the wait_for_suppliers list. The consumer device will never be
- * probed until it's removed from the wait_for_suppliers list.
- *
- * The caller is responsible for adding the links to the supplier devices once
- * they are available and removing the @consumer device from the
- * wait_for_suppliers list once links to all the suppliers have been created.
- *
- * This function is NOT meant to be called from the probe function of the
- * consumer but rather from code that creates/adds the consumer device.
- */
-static void device_link_wait_for_supplier(struct device *consumer,
-					  bool need_for_probe)
-{
-	mutex_lock(&wfs_lock);
-	list_add_tail(&consumer->links.needs_suppliers, &wait_for_suppliers);
-	consumer->links.need_for_probe = need_for_probe;
-	mutex_unlock(&wfs_lock);
-}
-
-static void device_link_wait_for_mandatory_supplier(struct device *consumer)
-{
-	device_link_wait_for_supplier(consumer, true);
-}
-
-static void device_link_wait_for_optional_supplier(struct device *consumer)
-{
-	device_link_wait_for_supplier(consumer, false);
-}
-
-/**
- * device_link_add_missing_supplier_links - Add links from consumer devices to
- *					    supplier devices, leaving any
- *					    consumer with inactive suppliers on
- *					    the wait_for_suppliers list
- *
- * Loops through all consumers waiting on suppliers and tries to add all their
- * supplier links. If that succeeds, the consumer device is removed from
- * wait_for_suppliers list. Otherwise, they are left in the wait_for_suppliers
- * list.  Devices left on the wait_for_suppliers list will not be probed.
- *
- * The fwnode add_links callback is expected to return 0 if it has found and
- * added all the supplier links for the consumer device. It should return an
- * error if it isn't able to do so.
- *
- * The caller of device_link_wait_for_supplier() is expected to call this once
- * it's aware of potential suppliers becoming available.
- */
-static void device_link_add_missing_supplier_links(void)
-{
-	struct device *dev, *tmp;
-
-	mutex_lock(&wfs_lock);
-	list_for_each_entry_safe(dev, tmp, &wait_for_suppliers,
-				 links.needs_suppliers) {
-		int ret = fwnode_call_int_op(dev->fwnode, add_links, dev);
-		if (!ret)
-			list_del_init(&dev->links.needs_suppliers);
-		else if (ret != -ENODEV || fw_devlink_is_permissive())
-			dev->links.need_for_probe = false;
-	}
-	mutex_unlock(&wfs_lock);
-}
-
 #ifdef CONFIG_SRCU
 static void __device_link_del(struct kref *kref)
 {
@@ -890,13 +926,13 @@ int device_links_check_suppliers(struct device *dev)
 	 * Device waiting for supplier to become available is not allowed to
 	 * probe.
 	 */
-	mutex_lock(&wfs_lock);
-	if (!list_empty(&dev->links.needs_suppliers) &&
-	    dev->links.need_for_probe) {
-		mutex_unlock(&wfs_lock);
+	mutex_lock(&fwnode_link_lock);
+	if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) &&
+	    !fw_devlink_is_permissive()) {
+		mutex_unlock(&fwnode_link_lock);
 		return -EPROBE_DEFER;
 	}
-	mutex_unlock(&wfs_lock);
+	mutex_unlock(&fwnode_link_lock);
 
 	device_links_write_lock();
 
@@ -960,11 +996,11 @@ static void __device_links_queue_sync_state(struct device *dev,
 	 */
 	dev->state_synced = true;
 
-	if (WARN_ON(!list_empty(&dev->links.defer_hook)))
+	if (WARN_ON(!list_empty(&dev->links.defer_sync)))
 		return;
 
 	get_device(dev);
-	list_add_tail(&dev->links.defer_hook, list);
+	list_add_tail(&dev->links.defer_sync, list);
 }
 
 /**
@@ -982,8 +1018,8 @@ static void device_links_flush_sync_list(struct list_head *list,
 {
 	struct device *dev, *tmp;
 
-	list_for_each_entry_safe(dev, tmp, list, links.defer_hook) {
-		list_del_init(&dev->links.defer_hook);
+	list_for_each_entry_safe(dev, tmp, list, links.defer_sync) {
+		list_del_init(&dev->links.defer_sync);
 
 		if (dev != dont_lock_dev)
 			device_lock(dev);
@@ -1021,12 +1057,12 @@ void device_links_supplier_sync_state_resume(void)
 	if (defer_sync_state_count)
 		goto out;
 
-	list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_hook) {
+	list_for_each_entry_safe(dev, tmp, &deferred_sync, links.defer_sync) {
 		/*
 		 * Delete from deferred_sync list before queuing it to
-		 * sync_list because defer_hook is used for both lists.
+		 * sync_list because defer_sync is used for both lists.
 		 */
-		list_del_init(&dev->links.defer_hook);
+		list_del_init(&dev->links.defer_sync);
 		__device_links_queue_sync_state(dev, &sync_list);
 	}
 out:
@@ -1044,8 +1080,8 @@ late_initcall(sync_state_resume_initcall);
 
 static void __device_links_supplier_defer_sync(struct device *sup)
 {
-	if (list_empty(&sup->links.defer_hook) && dev_has_sync_state(sup))
-		list_add_tail(&sup->links.defer_hook, &deferred_sync);
+	if (list_empty(&sup->links.defer_sync) && dev_has_sync_state(sup))
+		list_add_tail(&sup->links.defer_sync, &deferred_sync);
 }
 
 static void device_link_drop_managed(struct device_link *link)
@@ -1062,10 +1098,7 @@ static ssize_t waiting_for_supplier_show(struct device *dev,
 	bool val;
 
 	device_lock(dev);
-	mutex_lock(&wfs_lock);
-	val = !list_empty(&dev->links.needs_suppliers)
-	      && dev->links.need_for_probe;
-	mutex_unlock(&wfs_lock);
+	val = !list_empty(&dev->fwnode->suppliers);
 	device_unlock(dev);
 	return sysfs_emit(buf, "%u\n", val);
 }
@@ -1092,9 +1125,8 @@ void device_links_driver_bound(struct device *dev)
 	 * the device links it needs to or make new device links as it needs
 	 * them. So, it no longer needs to wait on any suppliers.
 	 */
-	mutex_lock(&wfs_lock);
-	list_del_init(&dev->links.needs_suppliers);
-	mutex_unlock(&wfs_lock);
+	if (dev->fwnode && dev->fwnode->dev == dev)
+		fwnode_links_purge_suppliers(dev->fwnode);
 	device_remove_file(dev, &dev_attr_waiting_for_supplier);
 
 	device_links_write_lock();
@@ -1275,7 +1307,7 @@ void device_links_driver_cleanup(struct device *dev)
 		WRITE_ONCE(link->status, DL_STATE_DORMANT);
 	}
 
-	list_del_init(&dev->links.defer_hook);
+	list_del_init(&dev->links.defer_sync);
 	__device_links_no_driver(dev);
 
 	device_links_write_unlock();
@@ -1385,10 +1417,6 @@ static void device_links_purge(struct device *dev)
 	if (dev->class == &devlink_class)
 		return;
 
-	mutex_lock(&wfs_lock);
-	list_del(&dev->links.needs_suppliers);
-	mutex_unlock(&wfs_lock);
-
 	/*
 	 * Delete all of the remaining links from this device to any other
 	 * devices (either consumers or suppliers).
@@ -1439,139 +1467,267 @@ static bool fw_devlink_is_permissive(void)
 	return fw_devlink_flags == DL_FLAG_SYNC_STATE_ONLY;
 }
 
-static void fw_devlink_link_device(struct device *dev)
+static void fw_devlink_parse_fwnode(struct fwnode_handle *fwnode)
 {
-	int fw_ret;
-
-	if (!fw_devlink_flags)
+	if (fwnode->flags & FWNODE_FLAG_LINKS_ADDED)
 		return;
 
-	mutex_lock(&defer_fw_devlink_lock);
-	if (!defer_fw_devlink_count)
-		device_link_add_missing_supplier_links();
+	fwnode_call_int_op(fwnode, add_links);
+	fwnode->flags |= FWNODE_FLAG_LINKS_ADDED;
+}
+
+static void fw_devlink_parse_fwtree(struct fwnode_handle *fwnode)
+{
+	struct fwnode_handle *child = NULL;
+
+	fw_devlink_parse_fwnode(fwnode);
+
+	while ((child = fwnode_get_next_available_child_node(fwnode, child)))
+		fw_devlink_parse_fwtree(child);
+}
 
+/**
+ * fw_devlink_create_devlink - Create a device link from a consumer to fwnode
+ * @con - Consumer device for the device link
+ * @sup_handle - fwnode handle of supplier
+ *
+ * This function will try to create a device link between the consumer device
+ * @con and the supplier device represented by @sup_handle.
+ *
+ * The supplier has to be provided as a fwnode because incorrect cycles in
+ * fwnode links can sometimes cause the supplier device to never be created.
+ * This function detects such cases and returns an error if it cannot create a
+ * device link from the consumer to a missing supplier.
+ *
+ * Returns,
+ * 0 on successfully creating a device link
+ * -EINVAL if the device link cannot be created as expected
+ * -EAGAIN if the device link cannot be created right now, but it may be
+ *  possible to do that in the future
+ */
+static int fw_devlink_create_devlink(struct device *con,
+				     struct fwnode_handle *sup_handle, u32 flags)
+{
+	struct device *sup_dev;
+	int ret = 0;
+
+	sup_dev = get_dev_from_fwnode(sup_handle);
+	if (sup_dev) {
 		/*
-	 * The device's fwnode not having add_links() doesn't affect if other
-	 * consumers can find this device as a supplier.  So, this check is
-	 * intentionally placed after device_link_add_missing_supplier_links().
+		 * If this fails, it is due to cycles in device links.  Just
+		 * give up on this link and treat it as invalid.
 		 */
-	if (!fwnode_has_op(dev->fwnode, add_links))
+		if (!device_link_add(con, sup_dev, flags))
+			ret = -EINVAL;
+
 		goto out;
+	}
 
 	/*
-	 * If fw_devlink is being deferred, assume all devices have mandatory
-	 * suppliers they need to link to later. Then, when the fw_devlink is
-	 * resumed, all these devices will get a chance to try and link to any
-	 * suppliers they have.
+	 * DL_FLAG_SYNC_STATE_ONLY doesn't block probing and supports
+	 * cycles. So cycle detection isn't necessary and shouldn't be
+	 * done.
 	 */
-	if (!defer_fw_devlink_count) {
-		fw_ret = fwnode_call_int_op(dev->fwnode, add_links, dev);
-		if (fw_ret == -ENODEV && fw_devlink_is_permissive())
-			fw_ret = -EAGAIN;
+	if (flags & DL_FLAG_SYNC_STATE_ONLY)
+		return -EAGAIN;
+
+	/*
+	 * If we can't find the supplier device from its fwnode, it might be
+	 * due to a cyclic dependency between fwnodes. Some of these cycles can
+	 * be broken by applying logic. Check for these types of cycles and
+	 * break them so that devices in the cycle probe properly.
+	 *
+	 * If the supplier's parent is dependent on the consumer, then
+	 * the consumer-supplier dependency is a false dependency. So,
+	 * treat it as an invalid link.
+	 */
+	sup_dev = fwnode_get_next_parent_dev(sup_handle);
+	if (sup_dev && device_is_dependent(con, sup_dev)) {
+		dev_dbg(con, "Not linking to %pfwP - False link\n",
+			sup_handle);
+		ret = -EINVAL;
 	} else {
-		fw_ret = -ENODEV;
 		/*
-		 * defer_hook is not used to add device to deferred_sync list
-		 * until device is bound. Since deferred fw devlink also blocks
-		 * probing, same list hook can be used for deferred_fw_devlink.
+		 * Can't check for cycles or no cycles. So let's try
+		 * again later.
 		 */
-		list_add_tail(&dev->links.defer_hook, &deferred_fw_devlink);
+		ret = -EAGAIN;
 	}
 
-	if (fw_ret == -ENODEV)
-		device_link_wait_for_mandatory_supplier(dev);
-	else if (fw_ret)
-		device_link_wait_for_optional_supplier(dev);
-
 out:
-	mutex_unlock(&defer_fw_devlink_lock);
+	put_device(sup_dev);
+	return ret;
 }
 
 /**
- * fw_devlink_pause - Pause parsing of fwnode to create device links
- *
- * Calling this function defers any fwnode parsing to create device links until
- * fw_devlink_resume() is called. Both these functions are ref counted and the
- * caller needs to match the calls.
- *
- * While fw_devlink is paused:
- * - Any device that is added won't have its fwnode parsed to create device
- *   links.
- * - The probe of the device will also be deferred during this period.
- * - Any devices that were already added, but waiting for suppliers won't be
- *   able to link to newly added devices.
- *
- * Once fw_devlink_resume():
- * - All the fwnodes that was not parsed will be parsed.
- * - All the devices that were deferred probing will be reattempted if they
- *   aren't waiting for any more suppliers.
- *
- * This pair of functions, is mainly meant to optimize the parsing of fwnodes
- * when a lot of devices that need to link to each other are added in a short
- * interval of time. For example, adding all the top level devices in a system.
- *
- * For example, if N devices are added and:
- * - All the consumers are added before their suppliers
- * - All the suppliers of the N devices are part of the N devices
- *
- * Then:
- *
- * - With the use of fw_devlink_pause() and fw_devlink_resume(), each device
- *   will only need one parsing of its fwnode because it is guaranteed to find
- *   all the supplier devices already registered and ready to link to. It won't
- *   have to do another pass later to find one or more suppliers it couldn't
- *   find in the first parse of the fwnode. So, we'll only need O(N) fwnode
- *   parses.
- *
- * - Without the use of fw_devlink_pause() and fw_devlink_resume(), we would
- *   end up doing O(N^2) parses of fwnodes because every device that's added is
- *   guaranteed to trigger a parse of the fwnode of every device added before
- *   it. This O(N^2) parse is made worse by the fact that when a fwnode of a
- *   device is parsed, all it descendant devices might need to have their
- *   fwnodes parsed too (even if the devices themselves aren't added).
+ * __fw_devlink_link_to_consumers - Create device links to consumers of a device
+ * @dev - Device that needs to be linked to its consumers
+ *
+ * This function looks at all the consumer fwnodes of @dev and creates device
+ * links between the consumer device and @dev (supplier).
+ *
+ * If the consumer device has not been added yet, then this function creates a
+ * SYNC_STATE_ONLY link between @dev (supplier) and the closest ancestor device
+ * of the consumer fwnode. This is necessary to make sure @dev doesn't get a
+ * sync_state() callback before the real consumer device gets to be added and
+ * then probed.
+ *
+ * Once device links are created from the real consumer to @dev (supplier), the
+ * fwnode links are deleted.
  */
-void fw_devlink_pause(void)
+static void __fw_devlink_link_to_consumers(struct device *dev)
 {
-	mutex_lock(&defer_fw_devlink_lock);
-	defer_fw_devlink_count++;
-	mutex_unlock(&defer_fw_devlink_lock);
+	struct fwnode_handle *fwnode = dev->fwnode;
+	struct fwnode_link *link, *tmp;
+
+	list_for_each_entry_safe(link, tmp, &fwnode->consumers, s_hook) {
+		u32 dl_flags = fw_devlink_get_flags();
+		struct device *con_dev;
+		bool own_link = true;
+		int ret;
+
+		con_dev = get_dev_from_fwnode(link->consumer);
+		/*
+		 * If consumer device is not available yet, make a "proxy"
+		 * SYNC_STATE_ONLY link from the consumer's parent device to
+		 * the supplier device. This is necessary to make sure the
+		 * supplier doesn't get a sync_state() callback before the real
+		 * consumer can create a device link to the supplier.
+		 *
+		 * This proxy link step is needed to handle the case where the
+		 * consumer's parent device is added before the supplier.
+		 */
+		if (!con_dev) {
+			con_dev = fwnode_get_next_parent_dev(link->consumer);
+			/*
+			 * However, if the consumer's parent device is also the
+			 * parent of the supplier, don't create a
+			 * consumer-supplier link from the parent to its child
+			 * device. Such a dependency is impossible.
+			 */
+			if (con_dev &&
+			    fwnode_is_ancestor_of(con_dev->fwnode, fwnode)) {
+				put_device(con_dev);
+				con_dev = NULL;
+			} else {
+				own_link = false;
+				dl_flags = DL_FLAG_SYNC_STATE_ONLY;
+			}
+		}
+
+		if (!con_dev)
+			continue;
+
+		ret = fw_devlink_create_devlink(con_dev, fwnode, dl_flags);
+		put_device(con_dev);
+		if (!own_link || ret == -EAGAIN)
+			continue;
+
+		list_del(&link->s_hook);
+		list_del(&link->c_hook);
+		kfree(link);
+	}
 }
 
-/** fw_devlink_resume - Resume parsing of fwnode to create device links
- *
- * This function is used in conjunction with fw_devlink_pause() and is ref
- * counted. See documentation for fw_devlink_pause() for more details.
+/**
+ * __fw_devlink_link_to_suppliers - Create device links to suppliers of a device
+ * @dev - The consumer device that needs to be linked to its suppliers
+ * @fwnode - Root of the fwnode tree that is used to create device links
+ *
+ * This function looks at all the supplier fwnodes of fwnode tree rooted at
+ * @fwnode and creates device links between @dev (consumer) and all the
+ * supplier devices of the entire fwnode tree at @fwnode.
+ *
+ * The function creates normal (non-SYNC_STATE_ONLY) device links between @dev
+ * and the real suppliers of @dev. Once these device links are created, the
+ * fwnode links are deleted. When such device links are successfully created,
+ * this function is called recursively on those supplier devices. This is
+ * needed to detect and break some invalid cycles in fwnode links.  See
+ * fw_devlink_create_devlink() for more details.
+ *
+ * In addition, it also looks at all the suppliers of the entire fwnode tree
+ * because some of the child devices of @dev that have not been added yet
+ * (because @dev hasn't probed) might already have their suppliers added to
+ * driver core. So, this function creates SYNC_STATE_ONLY device links between
+ * @dev (consumer) and these suppliers to make sure they don't execute their
+ * sync_state() callbacks before these child devices have a chance to create
+ * their device links. The fwnode links that correspond to the child devices
+ * aren't delete because they are needed later to create the device links
+ * between the real consumer and supplier devices.
  */
-void fw_devlink_resume(void)
+static void __fw_devlink_link_to_suppliers(struct device *dev,
+					   struct fwnode_handle *fwnode)
 {
-	struct device *dev, *tmp;
-	LIST_HEAD(probe_list);
+	bool own_link = (dev->fwnode == fwnode);
+	struct fwnode_link *link, *tmp;
+	struct fwnode_handle *child = NULL;
+	u32 dl_flags;
 
-	mutex_lock(&defer_fw_devlink_lock);
-	if (!defer_fw_devlink_count) {
-		WARN(true, "Unmatched fw_devlink pause/resume!");
-		goto out;
-	}
+	if (own_link)
+		dl_flags = fw_devlink_get_flags();
+	else
+		dl_flags = DL_FLAG_SYNC_STATE_ONLY;
 
-	defer_fw_devlink_count--;
-	if (defer_fw_devlink_count)
-		goto out;
+	list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) {
+		int ret;
+		struct device *sup_dev;
+		struct fwnode_handle *sup = link->supplier;
 
-	device_link_add_missing_supplier_links();
-	list_splice_tail_init(&deferred_fw_devlink, &probe_list);
-out:
-	mutex_unlock(&defer_fw_devlink_lock);
+		ret = fw_devlink_create_devlink(dev, sup, dl_flags);
+		if (!own_link || ret == -EAGAIN)
+			continue;
+
+		list_del(&link->s_hook);
+		list_del(&link->c_hook);
+		kfree(link);
+
+		/* If no device link was created, nothing more to do. */
+		if (ret)
+			continue;
 
 		/*
-	 * bus_probe_device() can cause new devices to get added and they'll
-	 * try to grab defer_fw_devlink_lock. So, this needs to be done outside
-	 * the defer_fw_devlink_lock.
+		 * If a device link was successfully created to a supplier, we
+		 * now need to try and link the supplier to all its suppliers.
+		 *
+		 * This is needed to detect and delete false dependencies in
+		 * fwnode links that haven't been converted to a device link
+		 * yet. See comments in fw_devlink_create_devlink() for more
+		 * details on the false dependency.
+		 *
+		 * Without deleting these false dependencies, some devices will
+		 * never probe because they'll keep waiting for their false
+		 * dependency fwnode links to be converted to device links.
 		 */
-	list_for_each_entry_safe(dev, tmp, &probe_list, links.defer_hook) {
-		list_del_init(&dev->links.defer_hook);
-		bus_probe_device(dev);
+		sup_dev = get_dev_from_fwnode(sup);
+		__fw_devlink_link_to_suppliers(sup_dev, sup_dev->fwnode);
+		put_device(sup_dev);
 	}
+
+	/*
+	 * Make "proxy" SYNC_STATE_ONLY device links to represent the needs of
+	 * all the descendants. This proxy link step is needed to handle the
+	 * case where the supplier is added before the consumer's parent device
+	 * (@dev).
+	 */
+	while ((child = fwnode_get_next_available_child_node(fwnode, child)))
+		__fw_devlink_link_to_suppliers(dev, child);
+}
+
+static void fw_devlink_link_device(struct device *dev)
+{
+	struct fwnode_handle *fwnode = dev->fwnode;
+
+	if (!fw_devlink_flags)
+		return;
+
+	fw_devlink_parse_fwtree(fwnode);
+
+	mutex_lock(&fwnode_link_lock);
+	__fw_devlink_link_to_consumers(dev);
+	__fw_devlink_link_to_suppliers(dev, fwnode);
+	mutex_unlock(&fwnode_link_lock);
 }
+
 /* Device links support end. */
 
 int (*platform_notify)(struct device *dev) = NULL;
@@ -2196,7 +2352,7 @@ static int device_add_attrs(struct device *dev)
 			goto err_remove_dev_groups;
 	}
 
-	if (fw_devlink_flags && !fw_devlink_is_permissive()) {
+	if (fw_devlink_flags && !fw_devlink_is_permissive() && dev->fwnode) {
 		error = device_create_file(dev, &dev_attr_waiting_for_supplier);
 		if (error)
 			goto err_remove_dev_online;
@@ -2427,8 +2583,7 @@ void device_initialize(struct device *dev)
 #endif
 	INIT_LIST_HEAD(&dev->links.consumers);
 	INIT_LIST_HEAD(&dev->links.suppliers);
-	INIT_LIST_HEAD(&dev->links.needs_suppliers);
-	INIT_LIST_HEAD(&dev->links.defer_hook);
+	INIT_LIST_HEAD(&dev->links.defer_sync);
 	dev->links.status = DL_DEV_NO_DRIVER;
 }
 EXPORT_SYMBOL_GPL(device_initialize);

drivers/base/dd.c

@@ -370,6 +370,13 @@ static void driver_bound(struct device *dev)
 
 	device_pm_check_callbacks(dev);
 
+	/*
+	 * Reorder successfully probed devices to the end of the device list.
+	 * This ensures that suspend/resume order matches probe order, which
+	 * is usually what drivers rely on.
+	 */
+	device_pm_move_to_tail(dev);
+
 	/*
 	 * Make sure the device is no longer in one of the deferred lists and
 	 * kick off retrying all pending devices
@@ -717,7 +724,7 @@ EXPORT_SYMBOL_GPL(wait_for_device_probe);
  *
  * If the device has a parent, runtime-resume the parent before driver probing.
  */
-int driver_probe_device(struct device_driver *drv, struct device *dev)
+static int driver_probe_device(struct device_driver *drv, struct device *dev)
 {
 	int ret = 0;
 

drivers/base/devres.c

@@ -149,7 +149,7 @@ void * __devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid
 EXPORT_SYMBOL_GPL(__devres_alloc_node);
 #else
 /**
- * devres_alloc - Allocate device resource data
+ * devres_alloc_node - Allocate device resource data
  * @release: Release function devres will be associated with
  * @size: Allocation size
  * @gfp: Allocation flags

drivers/base/firmware_loader/fallback.c

@@ -128,7 +128,7 @@ static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 }
 
 /**
- * firmware_timeout_store() - set number of seconds to wait for firmware
+ * timeout_store() - set number of seconds to wait for firmware
  * @class: device class pointer
  * @attr: device attribute pointer
  * @buf: buffer to scan for timeout value

drivers/base/platform.c

@@ -63,6 +63,21 @@ struct resource *platform_get_resource(struct platform_device *dev,
 }
 EXPORT_SYMBOL_GPL(platform_get_resource);
 
+struct resource *platform_get_mem_or_io(struct platform_device *dev,
+					unsigned int num)
+{
+	u32 i;
+
+	for (i = 0; i < dev->num_resources; i++) {
+		struct resource *r = &dev->resource[i];
+
+		if ((resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) && num-- == 0)
+			return r;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(platform_get_mem_or_io);
+
 #ifdef CONFIG_HAS_IOMEM
 /**
  * devm_platform_get_and_ioremap_resource - call devm_ioremap_resource() for a
@@ -743,62 +758,6 @@ struct platform_device *platform_device_register_full(
 }
 EXPORT_SYMBOL_GPL(platform_device_register_full);
 
-static int platform_drv_probe(struct device *_dev)
-{
-	struct platform_driver *drv = to_platform_driver(_dev->driver);
-	struct platform_device *dev = to_platform_device(_dev);
-	int ret;
-
-	ret = of_clk_set_defaults(_dev->of_node, false);
-	if (ret < 0)
-		return ret;
-
-	ret = dev_pm_domain_attach(_dev, true);
-	if (ret)
-		goto out;
-
-	if (drv->probe) {
-		ret = drv->probe(dev);
-		if (ret)
-			dev_pm_domain_detach(_dev, true);
-	}
-
-out:
-	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
-		dev_warn(_dev, "probe deferral not supported\n");
-		ret = -ENXIO;
-	}
-
-	return ret;
-}
-
-static int platform_drv_probe_fail(struct device *_dev)
-{
-	return -ENXIO;
-}
-
-static int platform_drv_remove(struct device *_dev)
-{
-	struct platform_driver *drv = to_platform_driver(_dev->driver);
-	struct platform_device *dev = to_platform_device(_dev);
-	int ret = 0;
-
-	if (drv->remove)
-		ret = drv->remove(dev);
-	dev_pm_domain_detach(_dev, true);
-
-	return ret;
-}
-
-static void platform_drv_shutdown(struct device *_dev)
-{
-	struct platform_driver *drv = to_platform_driver(_dev->driver);
-	struct platform_device *dev = to_platform_device(_dev);
-
-	if (drv->shutdown)
-		drv->shutdown(dev);
-}
-
 /**
  * __platform_driver_register - register a driver for platform-level devices
  * @drv: platform driver structure
@@ -809,9 +768,6 @@ int __platform_driver_register(struct platform_driver *drv,
 {
 	drv->driver.owner = owner;
 	drv->driver.bus = &platform_bus_type;
-	drv->driver.probe = platform_drv_probe;
-	drv->driver.remove = platform_drv_remove;
-	drv->driver.shutdown = platform_drv_shutdown;
 
 	return driver_register(&drv->driver);
 }
@@ -827,6 +783,11 @@ void platform_driver_unregister(struct platform_driver *drv)
 }
 EXPORT_SYMBOL_GPL(platform_driver_unregister);
 
+static int platform_probe_fail(struct platform_device *pdev)
+{
+	return -ENXIO;
+}
+
 /**
  * __platform_driver_probe - register driver for non-hotpluggable device
  * @drv: platform driver structure
@@ -887,10 +848,9 @@ int __init_or_module __platform_driver_probe(struct platform_driver *drv,
 	 * new devices fail.
 	 */
 	spin_lock(&drv->driver.bus->p->klist_drivers.k_lock);
-	drv->probe = NULL;
+	drv->probe = platform_probe_fail;
 	if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list))
 		retval = -ENODEV;
-	drv->driver.probe = platform_drv_probe_fail;
 	spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock);
 
 	if (code != retval)
@@ -1017,129 +977,6 @@ void platform_unregister_drivers(struct platform_driver * const *drivers,
 }
 EXPORT_SYMBOL_GPL(platform_unregister_drivers);
 
-/* modalias support enables more hands-off userspace setup:
- * (a) environment variable lets new-style hotplug events work once system is
- *     fully running:  "modprobe $MODALIAS"
- * (b) sysfs attribute lets new-style coldplug recover from hotplug events
- *     mishandled before system is fully running:  "modprobe $(cat modalias)"
- */
-static ssize_t modalias_show(struct device *dev,
-			     struct device_attribute *attr, char *buf)
-{
-	struct platform_device *pdev = to_platform_device(dev);
-	int len;
-
-	len = of_device_modalias(dev, buf, PAGE_SIZE);
-	if (len != -ENODEV)
-		return len;
-
-	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
-	if (len != -ENODEV)
-		return len;
-
-	return sysfs_emit(buf, "platform:%s\n", pdev->name);
-}
-static DEVICE_ATTR_RO(modalias);
-
-static ssize_t driver_override_store(struct device *dev,
-				     struct device_attribute *attr,
-				     const char *buf, size_t count)
-{
-	struct platform_device *pdev = to_platform_device(dev);
-	char *driver_override, *old, *cp;
-
-	/* We need to keep extra room for a newline */
-	if (count >= (PAGE_SIZE - 1))
-		return -EINVAL;
-
-	driver_override = kstrndup(buf, count, GFP_KERNEL);
-	if (!driver_override)
-		return -ENOMEM;
-
-	cp = strchr(driver_override, '\n');
-	if (cp)
-		*cp = '\0';
-
-	device_lock(dev);
-	old = pdev->driver_override;
-	if (strlen(driver_override)) {
-		pdev->driver_override = driver_override;
-	} else {
-		kfree(driver_override);
-		pdev->driver_override = NULL;
-	}
-	device_unlock(dev);
-
-	kfree(old);
-
-	return count;
-}
-
-static ssize_t driver_override_show(struct device *dev,
-				    struct device_attribute *attr, char *buf)
-{
-	struct platform_device *pdev = to_platform_device(dev);
-	ssize_t len;
-
-	device_lock(dev);
-	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
-	device_unlock(dev);
-
-	return len;
-}
-static DEVICE_ATTR_RW(driver_override);
-
-static ssize_t numa_node_show(struct device *dev,
-			      struct device_attribute *attr, char *buf)
-{
-	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
-}
-static DEVICE_ATTR_RO(numa_node);
-
-static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
-		int n)
-{
-	struct device *dev = container_of(kobj, typeof(*dev), kobj);
-
-	if (a == &dev_attr_numa_node.attr &&
-			dev_to_node(dev) == NUMA_NO_NODE)
-		return 0;
-
-	return a->mode;
-}
-
-static struct attribute *platform_dev_attrs[] = {
-	&dev_attr_modalias.attr,
-	&dev_attr_numa_node.attr,
-	&dev_attr_driver_override.attr,
-	NULL,
-};
-
-static struct attribute_group platform_dev_group = {
-	.attrs = platform_dev_attrs,
-	.is_visible = platform_dev_attrs_visible,
-};
-__ATTRIBUTE_GROUPS(platform_dev);
-
-static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
-	struct platform_device	*pdev = to_platform_device(dev);
-	int rc;
-
-	/* Some devices have extra OF data and an OF-style MODALIAS */
-	rc = of_device_uevent_modalias(dev, env);
-	if (rc != -ENODEV)
-		return rc;
-
-	rc = acpi_device_uevent_modalias(dev, env);
-	if (rc != -ENODEV)
-		return rc;
-
-	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
-			pdev->name);
-	return 0;
-}
-
 static const struct platform_device_id *platform_match_id(
 			const struct platform_device_id *id,
 			struct platform_device *pdev)
@@ -1154,44 +991,6 @@ static const struct platform_device_id *platform_match_id(
 	return NULL;
 }
 
-/**
- * platform_match - bind platform device to platform driver.
- * @dev: device.
- * @drv: driver.
- *
- * Platform device IDs are assumed to be encoded like this:
- * "<name><instance>", where <name> is a short description of the type of
- * device, like "pci" or "floppy", and <instance> is the enumerated
- * instance of the device, like '0' or '42'.  Driver IDs are simply
- * "<name>".  So, extract the <name> from the platform_device structure,
- * and compare it against the name of the driver. Return whether they match
- * or not.
- */
-static int platform_match(struct device *dev, struct device_driver *drv)
-{
-	struct platform_device *pdev = to_platform_device(dev);
-	struct platform_driver *pdrv = to_platform_driver(drv);
-
-	/* When driver_override is set, only bind to the matching driver */
-	if (pdev->driver_override)
-		return !strcmp(pdev->driver_override, drv->name);
-
-	/* Attempt an OF style match first */
-	if (of_driver_match_device(dev, drv))
-		return 1;
-
-	/* Then try ACPI style match */
-	if (acpi_driver_match_device(dev, drv))
-		return 1;
-
-	/* Then try to match against the id table */
-	if (pdrv->id_table)
-		return platform_match_id(pdrv->id_table, pdev) != NULL;
-
-	/* fall-back to driver name match */
-	return (strcmp(pdev->name, drv->name) == 0);
-}
-
 #ifdef CONFIG_PM_SLEEP
 
 static int platform_legacy_suspend(struct device *dev, pm_message_t mesg)
@@ -1336,6 +1135,234 @@ int platform_pm_restore(struct device *dev)
 
 #endif /* CONFIG_HIBERNATE_CALLBACKS */
 
+/* modalias support enables more hands-off userspace setup:
+ * (a) environment variable lets new-style hotplug events work once system is
+ *     fully running:  "modprobe $MODALIAS"
+ * (b) sysfs attribute lets new-style coldplug recover from hotplug events
+ *     mishandled before system is fully running:  "modprobe $(cat modalias)"
+ */
+static ssize_t modalias_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	int len;
+
+	len = of_device_modalias(dev, buf, PAGE_SIZE);
+	if (len != -ENODEV)
+		return len;
+
+	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
+	if (len != -ENODEV)
+		return len;
+
+	return sysfs_emit(buf, "platform:%s\n", pdev->name);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static ssize_t numa_node_show(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%d\n", dev_to_node(dev));
+}
+static DEVICE_ATTR_RO(numa_node);
+
+static ssize_t driver_override_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	ssize_t len;
+
+	device_lock(dev);
+	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
+	device_unlock(dev);
+
+	return len;
+}
+
+static ssize_t driver_override_store(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	char *driver_override, *old, *cp;
+
+	/* We need to keep extra room for a newline */
+	if (count >= (PAGE_SIZE - 1))
+		return -EINVAL;
+
+	driver_override = kstrndup(buf, count, GFP_KERNEL);
+	if (!driver_override)
+		return -ENOMEM;
+
+	cp = strchr(driver_override, '\n');
+	if (cp)
+		*cp = '\0';
+
+	device_lock(dev);
+	old = pdev->driver_override;
+	if (strlen(driver_override)) {
+		pdev->driver_override = driver_override;
+	} else {
+		kfree(driver_override);
+		pdev->driver_override = NULL;
+	}
+	device_unlock(dev);
+
+	kfree(old);
+
+	return count;
+}
+static DEVICE_ATTR_RW(driver_override);
+
+static struct attribute *platform_dev_attrs[] = {
+	&dev_attr_modalias.attr,
+	&dev_attr_numa_node.attr,
+	&dev_attr_driver_override.attr,
+	NULL,
+};
+
+static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
+		int n)
+{
+	struct device *dev = container_of(kobj, typeof(*dev), kobj);
+
+	if (a == &dev_attr_numa_node.attr &&
+			dev_to_node(dev) == NUMA_NO_NODE)
+		return 0;
+
+	return a->mode;
+}
+
+static struct attribute_group platform_dev_group = {
+	.attrs = platform_dev_attrs,
+	.is_visible = platform_dev_attrs_visible,
+};
+__ATTRIBUTE_GROUPS(platform_dev);
+
+
+/**
+ * platform_match - bind platform device to platform driver.
+ * @dev: device.
+ * @drv: driver.
+ *
+ * Platform device IDs are assumed to be encoded like this:
+ * "<name><instance>", where <name> is a short description of the type of
+ * device, like "pci" or "floppy", and <instance> is the enumerated
+ * instance of the device, like '0' or '42'.  Driver IDs are simply
+ * "<name>".  So, extract the <name> from the platform_device structure,
+ * and compare it against the name of the driver. Return whether they match
+ * or not.
+ */
+static int platform_match(struct device *dev, struct device_driver *drv)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct platform_driver *pdrv = to_platform_driver(drv);
+
+	/* When driver_override is set, only bind to the matching driver */
+	if (pdev->driver_override)
+		return !strcmp(pdev->driver_override, drv->name);
+
+	/* Attempt an OF style match first */
+	if (of_driver_match_device(dev, drv))
+		return 1;
+
+	/* Then try ACPI style match */
+	if (acpi_driver_match_device(dev, drv))
+		return 1;
+
+	/* Then try to match against the id table */
+	if (pdrv->id_table)
+		return platform_match_id(pdrv->id_table, pdev) != NULL;
+
+	/* fall-back to driver name match */
+	return (strcmp(pdev->name, drv->name) == 0);
+}
+
+static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct platform_device	*pdev = to_platform_device(dev);
+	int rc;
+
+	/* Some devices have extra OF data and an OF-style MODALIAS */
+	rc = of_device_uevent_modalias(dev, env);
+	if (rc != -ENODEV)
+		return rc;
+
+	rc = acpi_device_uevent_modalias(dev, env);
+	if (rc != -ENODEV)
+		return rc;
+
+	add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX,
+			pdev->name);
+	return 0;
+}
+
+static int platform_probe(struct device *_dev)
+{
+	struct platform_driver *drv = to_platform_driver(_dev->driver);
+	struct platform_device *dev = to_platform_device(_dev);
+	int ret;
+
+	/*
+	 * A driver registered using platform_driver_probe() cannot be bound
+	 * again later because the probe function usually lives in __init code
+	 * and so is gone. For these drivers .probe is set to
+	 * platform_probe_fail in __platform_driver_probe(). Don't even prepare
+	 * clocks and PM domains for these to match the traditional behaviour.
+	 */
+	if (unlikely(drv->probe == platform_probe_fail))
+		return -ENXIO;
+
+	ret = of_clk_set_defaults(_dev->of_node, false);
+	if (ret < 0)
+		return ret;
+
+	ret = dev_pm_domain_attach(_dev, true);
+	if (ret)
+		goto out;
+
+	if (drv->probe) {
+		ret = drv->probe(dev);
+		if (ret)
+			dev_pm_domain_detach(_dev, true);
+	}
+
+out:
+	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
+		dev_warn(_dev, "probe deferral not supported\n");
+		ret = -ENXIO;
+	}
+
+	return ret;
+}
+
+static int platform_remove(struct device *_dev)
+{
+	struct platform_driver *drv = to_platform_driver(_dev->driver);
+	struct platform_device *dev = to_platform_device(_dev);
+	int ret = 0;
+
+	if (drv->remove)
+		ret = drv->remove(dev);
+	dev_pm_domain_detach(_dev, true);
+
+	return ret;
+}
+
+static void platform_shutdown(struct device *_dev)
+{
+	struct platform_device *dev = to_platform_device(_dev);
+	struct platform_driver *drv;
+
+	if (!_dev->driver)
+		return;
+
+	drv = to_platform_driver(_dev->driver);
+	if (drv->shutdown)
+		drv->shutdown(dev);
+}
+
+
 int platform_dma_configure(struct device *dev)
 {
 	enum dev_dma_attr attr;
@@ -1362,6 +1389,9 @@ struct bus_type platform_bus_type = {
 	.dev_groups	= platform_dev_groups,
 	.match		= platform_match,
 	.uevent		= platform_uevent,
+	.probe		= platform_probe,
+	.remove		= platform_remove,
+	.shutdown	= platform_shutdown,
 	.dma_configure	= platform_dma_configure,
 	.pm		= &platform_dev_pm_ops,
 };

drivers/base/property.c

@@ -614,6 +614,31 @@ struct fwnode_handle *fwnode_get_next_parent(struct fwnode_handle *fwnode)
 }
 EXPORT_SYMBOL_GPL(fwnode_get_next_parent);
 
+/**
+ * fwnode_get_next_parent_dev - Find device of closest ancestor fwnode
+ * @fwnode: firmware node
+ *
+ * Given a firmware node (@fwnode), this function finds its closest ancestor
+ * firmware node that has a corresponding struct device and returns that struct
+ * device.
+ *
+ * The caller of this function is expected to call put_device() on the returned
+ * device when they are done.
+ */
+struct device *fwnode_get_next_parent_dev(struct fwnode_handle *fwnode)
+{
+	struct device *dev = NULL;
+
+	fwnode_handle_get(fwnode);
+	do {
+		fwnode = fwnode_get_next_parent(fwnode);
+		if (fwnode)
+			dev = get_dev_from_fwnode(fwnode);
+	} while (fwnode && !dev);
+	fwnode_handle_put(fwnode);
+	return dev;
+}
+
 /**
  * fwnode_count_parents - Return the number of parents a node has
  * @fwnode: The node the parents of which are to be counted
@@ -660,6 +685,33 @@ struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwnode,
 }
 EXPORT_SYMBOL_GPL(fwnode_get_nth_parent);
 
+/**
+ * fwnode_is_ancestor_of - Test if @test_ancestor is ancestor of @test_child
+ * @test_ancestor: Firmware which is tested for being an ancestor
+ * @test_child: Firmware which is tested for being the child
+ *
+ * A node is considered an ancestor of itself too.
+ *
+ * Returns true if @test_ancestor is an ancestor of @test_child.
+ * Otherwise, returns false.
+ */
+bool fwnode_is_ancestor_of(struct fwnode_handle *test_ancestor,
+				  struct fwnode_handle *test_child)
+{
+	if (!test_ancestor)
+		return false;
+
+	fwnode_handle_get(test_child);
+	while (test_child) {
+		if (test_child == test_ancestor) {
+			fwnode_handle_put(test_child);
+			return true;
+		}
+		test_child = fwnode_get_next_parent(test_child);
+	}
+	return false;
+}
+
 /**
  * fwnode_get_next_child_node - Return the next child node handle for a node
  * @fwnode: Firmware node to find the next child node for.

drivers/base/soc.c

@@ -168,7 +168,7 @@ struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr
 }
 EXPORT_SYMBOL_GPL(soc_device_register);
 
-/* Ensure soc_dev->attr is freed prior to calling soc_device_unregister. */
+/* Ensure soc_dev->attr is freed after calling soc_device_unregister. */
 void soc_device_unregister(struct soc_device *soc_dev)
 {
 	device_unregister(&soc_dev->dev);

drivers/base/swnode.c

@@ -653,7 +653,7 @@ swnode_register(const struct software_node *node, struct swnode *parent,
 	swnode->parent = parent;
 	swnode->allocated = allocated;
 	swnode->kobj.kset = swnode_kset;
-	swnode->fwnode.ops = &software_node_ops;
+	fwnode_init(&swnode->fwnode, &software_node_ops);
 
 	ida_init(&swnode->child_ids);
 	INIT_LIST_HEAD(&swnode->entry);

drivers/firmware/efi/efi-init.c

@@ -316,11 +316,9 @@ static struct device_node *find_pci_overlap_node(void)
  * resource reservation conflict on the memory window that the efifb
  * framebuffer steals from the PCIe host bridge.
  */
-static int efifb_add_links(const struct fwnode_handle *fwnode,
-			   struct device *dev)
+static int efifb_add_links(struct fwnode_handle *fwnode)
 {
 	struct device_node *sup_np;
-	struct device *sup_dev;
 
 	sup_np = find_pci_overlap_node();
 
@@ -331,27 +329,9 @@ static int efifb_add_links(const struct fwnode_handle *fwnode,
 	if (!sup_np)
 		return 0;
 
-	sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
+	fwnode_link_add(fwnode, of_fwnode_handle(sup_np));
 	of_node_put(sup_np);
 
-	/*
-	 * Return -ENODEV if the PCI graphics controller device hasn't been
-	 * registered yet.  This ensures that efifb isn't allowed to probe
-	 * and this function is retried again when new devices are
-	 * registered.
-	 */
-	if (!sup_dev)
-		return -ENODEV;
-
-	/*
-	 * If this fails, retrying this function at a later point won't
-	 * change anything. So, don't return an error after this.
-	 */
-	if (!device_link_add(dev, sup_dev, fw_devlink_get_flags()))
-		dev_warn(dev, "device_link_add() failed\n");
-
-	put_device(sup_dev);
-
 	return 0;
 }
 
@@ -359,9 +339,7 @@ static const struct fwnode_operations efifb_fwnode_ops = {
 	.add_links = efifb_add_links,
 };
 
-static struct fwnode_handle efifb_fwnode = {
-	.ops = &efifb_fwnode_ops,
-};
+static struct fwnode_handle efifb_fwnode;
 
 static int __init register_gop_device(void)
 {
@@ -375,8 +353,10 @@ static int __init register_gop_device(void)
 	if (!pd)
 		return -ENOMEM;
 
-	if (IS_ENABLED(CONFIG_PCI))
+	if (IS_ENABLED(CONFIG_PCI)) {
+		fwnode_init(&efifb_fwnode, &efifb_fwnode_ops);
 		pd->dev.fwnode = &efifb_fwnode;
+	}
 
 	err = platform_device_add_data(pd, &screen_info, sizeof(screen_info));
 	if (err)

drivers/misc/pvpanic.c

@@ -8,14 +8,14 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#include <linux/acpi.h>
+#include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/kexec.h>
+#include <linux/mod_devicetable.h>
 #include <linux/module.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
 #include <linux/platform_device.h>
 #include <linux/types.h>
+
 #include <uapi/misc/pvpanic.h>
 
 static void __iomem *base;
@@ -49,101 +49,16 @@ static struct notifier_block pvpanic_panic_nb = {
 	.priority = 1, /* let this called before broken drm_fb_helper */
 };
 
-#ifdef CONFIG_ACPI
-static int pvpanic_add(struct acpi_device *device);
-static int pvpanic_remove(struct acpi_device *device);
-
-static const struct acpi_device_id pvpanic_device_ids[] = {
-	{ "QEMU0001", 0 },
-	{ "", 0 }
-};
-MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids);
-
-static struct acpi_driver pvpanic_driver = {
-	.name =		"pvpanic",
-	.class =	"QEMU",
-	.ids =		pvpanic_device_ids,
-	.ops =		{
-				.add =		pvpanic_add,
-				.remove =	pvpanic_remove,
-			},
-	.owner =	THIS_MODULE,
-};
-
-static acpi_status
-pvpanic_walk_resources(struct acpi_resource *res, void *context)
-{
-	struct resource r;
-
-	if (acpi_dev_resource_io(res, &r)) {
-#ifdef CONFIG_HAS_IOPORT_MAP
-		base = ioport_map(r.start, resource_size(&r));
-		return AE_OK;
-#else
-		return AE_ERROR;
-#endif
-	} else if (acpi_dev_resource_memory(res, &r)) {
-		base = ioremap(r.start, resource_size(&r));
-		return AE_OK;
-	}
-
-	return AE_ERROR;
-}
-
-static int pvpanic_add(struct acpi_device *device)
-{
-	int ret;
-
-	ret = acpi_bus_get_status(device);
-	if (ret < 0)
-		return ret;
-
-	if (!device->status.enabled || !device->status.functional)
-		return -ENODEV;
-
-	acpi_walk_resources(device->handle, METHOD_NAME__CRS,
-			    pvpanic_walk_resources, NULL);
-
-	if (!base)
-		return -ENODEV;
-
-	atomic_notifier_chain_register(&panic_notifier_list,
-				       &pvpanic_panic_nb);
-
-	return 0;
-}
-
-static int pvpanic_remove(struct acpi_device *device)
-{
-
-	atomic_notifier_chain_unregister(&panic_notifier_list,
-					 &pvpanic_panic_nb);
-	iounmap(base);
-
-	return 0;
-}
-
-static int pvpanic_register_acpi_driver(void)
-{
-	return acpi_bus_register_driver(&pvpanic_driver);
-}
-
-static void pvpanic_unregister_acpi_driver(void)
-{
-	acpi_bus_unregister_driver(&pvpanic_driver);
-}
-#else
-static int pvpanic_register_acpi_driver(void)
-{
-	return -ENODEV;
-}
-
-static void pvpanic_unregister_acpi_driver(void) {}
-#endif
-
 static int pvpanic_mmio_probe(struct platform_device *pdev)
 {
-	base = devm_platform_ioremap_resource(pdev, 0);
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+
+	res = platform_get_mem_or_io(pdev, 0);
+	if (res && resource_type(res) == IORESOURCE_IO)
+		base = devm_ioport_map(dev, res->start, resource_size(res));
+	else
+		base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 
@@ -167,30 +82,19 @@ static const struct of_device_id pvpanic_mmio_match[] = {
 	{}
 };
 
+static const struct acpi_device_id pvpanic_device_ids[] = {
+	{ "QEMU0001", 0 },
+	{ "", 0 }
+};
+MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids);
+
 static struct platform_driver pvpanic_mmio_driver = {
 	.driver = {
 		.name = "pvpanic-mmio",
 		.of_match_table = pvpanic_mmio_match,
+		.acpi_match_table = pvpanic_device_ids,
 	},
 	.probe = pvpanic_mmio_probe,
 	.remove = pvpanic_mmio_remove,
 };
-
-static int __init pvpanic_mmio_init(void)
-{
-	if (acpi_disabled)
-		return platform_driver_register(&pvpanic_mmio_driver);
-	else
-		return pvpanic_register_acpi_driver();
-}
-
-static void __exit pvpanic_mmio_exit(void)
-{
-	if (acpi_disabled)
-		platform_driver_unregister(&pvpanic_mmio_driver);
-	else
-		pvpanic_unregister_acpi_driver();
-}
-
-module_init(pvpanic_mmio_init);
-module_exit(pvpanic_mmio_exit);
+module_platform_driver(pvpanic_mmio_driver);

drivers/of/dynamic.c

@@ -356,6 +356,7 @@ void of_node_release(struct kobject *kobj)
 
 	property_list_free(node->properties);
 	property_list_free(node->deadprops);
+	fwnode_links_purge(of_fwnode_handle(node));
 
 	kfree(node->full_name);
 	kfree(node->data);

drivers/of/platform.c

@@ -538,9 +538,7 @@ static int __init of_platform_default_populate_init(void)
 	}
 
 	/* Populate everything else. */
-	fw_devlink_pause();
 	of_platform_default_populate(NULL, NULL, NULL);
-	fw_devlink_resume();
 
 	return 0;
 }

drivers/of/property.c

@@ -1038,33 +1038,9 @@ static bool of_is_ancestor_of(struct device_node *test_ancestor,
 }
 
 /**
- * of_get_next_parent_dev - Add device link to supplier from supplier phandle
- * @np: device tree node
- *
- * Given a device tree node (@np), this function finds its closest ancestor
- * device tree node that has a corresponding struct device.
- *
- * The caller of this function is expected to call put_device() on the returned
- * device when they are done.
- */
-static struct device *of_get_next_parent_dev(struct device_node *np)
-{
-	struct device *dev = NULL;
-
-	of_node_get(np);
-	do {
-		np = of_get_next_parent(np);
-		if (np)
-			dev = get_dev_from_fwnode(&np->fwnode);
-	} while (np && !dev);
-	of_node_put(np);
-	return dev;
-}
-
-/**
- * of_link_to_phandle - Add device link to supplier from supplier phandle
- * @dev: consumer device
- * @sup_np: phandle to supplier device tree node
+ * of_link_to_phandle - Add fwnode link to supplier from supplier phandle
+ * @con_np: consumer device tree node
+ * @sup_np: supplier device tree node
  *
  * Given a phandle to a supplier device tree node (@sup_np), this function
  * finds the device that owns the supplier device tree node and creates a
@@ -1074,16 +1050,14 @@ static struct device *of_get_next_parent_dev(struct device_node *np)
  * cases, it returns an error.
  *
  * Returns:
- * - 0 if link successfully created to supplier
- * - -EAGAIN if linking to the supplier should be reattempted
+ * - 0 if fwnode link successfully created to supplier
  * - -EINVAL if the supplier link is invalid and should not be created
- * - -ENODEV if there is no device that corresponds to the supplier phandle
+ * - -ENODEV if struct device will never be create for supplier
  */
-static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
-			      u32 dl_flags)
+static int of_link_to_phandle(struct device_node *con_np,
+			      struct device_node *sup_np)
 {
-	struct device *sup_dev, *sup_par_dev;
-	int ret = 0;
+	struct device *sup_dev;
 	struct device_node *tmp_np = sup_np;
 
 	of_node_get(sup_np);
@@ -1106,7 +1080,8 @@ static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
 	}
 
 	if (!sup_np) {
-		dev_dbg(dev, "Not linking to %pOFP - No device\n", tmp_np);
+		pr_debug("Not linking %pOFP to %pOFP - No device\n",
+			 con_np, tmp_np);
 		return -ENODEV;
 	}
 
@@ -1115,53 +1090,30 @@ static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
 	 * descendant nodes. By definition, a child node can't be a functional
 	 * dependency for the parent node.
 	 */
-	if (of_is_ancestor_of(dev->of_node, sup_np)) {
-		dev_dbg(dev, "Not linking to %pOFP - is descendant\n", sup_np);
+	if (of_is_ancestor_of(con_np, sup_np)) {
+		pr_debug("Not linking %pOFP to %pOFP - is descendant\n",
+			 con_np, sup_np);
 		of_node_put(sup_np);
 		return -EINVAL;
 	}
+
+	/*
+	 * Don't create links to "early devices" that won't have struct devices
+	 * created for them.
+	 */
 	sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
 	if (!sup_dev && of_node_check_flag(sup_np, OF_POPULATED)) {
-		/* Early device without struct device. */
-		dev_dbg(dev, "Not linking to %pOFP - No struct device\n",
-			sup_np);
+		pr_debug("Not linking %pOFP to %pOFP - No struct device\n",
+			 con_np, sup_np);
 		of_node_put(sup_np);
 		return -ENODEV;
-	} else if (!sup_dev) {
-		/*
-		 * DL_FLAG_SYNC_STATE_ONLY doesn't block probing and supports
-		 * cycles. So cycle detection isn't necessary and shouldn't be
-		 * done.
-		 */
-		if (dl_flags & DL_FLAG_SYNC_STATE_ONLY) {
-			of_node_put(sup_np);
-			return -EAGAIN;
-		}
-
-		sup_par_dev = of_get_next_parent_dev(sup_np);
-
-		if (sup_par_dev && device_is_dependent(dev, sup_par_dev)) {
-			/* Cyclic dependency detected, don't try to link */
-			dev_dbg(dev, "Not linking to %pOFP - cycle detected\n",
-				sup_np);
-			ret = -EINVAL;
-		} else {
-			/*
-			 * Can't check for cycles or no cycles. So let's try
-			 * again later.
-			 */
-			ret = -EAGAIN;
 	}
+	put_device(sup_dev);
 
+	fwnode_link_add(of_fwnode_handle(con_np), of_fwnode_handle(sup_np));
 	of_node_put(sup_np);
-		put_device(sup_par_dev);
-		return ret;
-	}
-	of_node_put(sup_np);
-	if (!device_link_add(dev, sup_dev, dl_flags))
-		ret = -EINVAL;
-	put_device(sup_dev);
-	return ret;
+
+	return 0;
 }
 
 /**
@@ -1361,37 +1313,29 @@ static const struct supplier_bindings of_supplier_bindings[] = {
  * that list phandles to suppliers. If @prop_name isn't one, this function
  * doesn't do anything.
  *
- * If @prop_name is one, this function attempts to create device links from the
- * consumer device @dev to all the devices of the suppliers listed in
- * @prop_name.
+ * If @prop_name is one, this function attempts to create fwnode links from the
+ * consumer device tree node @con_np to all the suppliers device tree nodes
+ * listed in @prop_name.
  *
- * Any failed attempt to create a device link will NOT result in an immediate
+ * Any failed attempt to create a fwnode link will NOT result in an immediate
  * return.  of_link_property() must create links to all the available supplier
- * devices even when attempts to create a link to one or more suppliers fail.
+ * device tree nodes even when attempts to create a link to one or more
+ * suppliers fail.
  */
-static int of_link_property(struct device *dev, struct device_node *con_np,
-			     const char *prop_name)
+static int of_link_property(struct device_node *con_np, const char *prop_name)
 {
 	struct device_node *phandle;
 	const struct supplier_bindings *s = of_supplier_bindings;
 	unsigned int i = 0;
 	bool matched = false;
 	int ret = 0;
-	u32 dl_flags;
-
-	if (dev->of_node == con_np)
-		dl_flags = fw_devlink_get_flags();
-	else
-		dl_flags = DL_FLAG_SYNC_STATE_ONLY;
 
 	/* Do not stop at first failed link, link all available suppliers. */
 	while (!matched && s->parse_prop) {
 		while ((phandle = s->parse_prop(con_np, prop_name, i))) {
 			matched = true;
 			i++;
-			if (of_link_to_phandle(dev, phandle, dl_flags)
-								== -EAGAIN)
-				ret = -EAGAIN;
+			of_link_to_phandle(con_np, phandle);
 			of_node_put(phandle);
 		}
 		s++;
@@ -1399,31 +1343,18 @@ static int of_link_property(struct device *dev, struct device_node *con_np,
 	return ret;
 }
 
-static int of_link_to_suppliers(struct device *dev,
-				  struct device_node *con_np)
+static int of_fwnode_add_links(struct fwnode_handle *fwnode)
 {
-	struct device_node *child;
 	struct property *p;
-	int ret = 0;
+	struct device_node *con_np = to_of_node(fwnode);
 
-	for_each_property_of_node(con_np, p)
-		if (of_link_property(dev, con_np, p->name))
-			ret = -ENODEV;
-
-	for_each_available_child_of_node(con_np, child)
-		if (of_link_to_suppliers(dev, child) && !ret)
-			ret = -EAGAIN;
+	if (!con_np)
+		return -EINVAL;
 
-	return ret;
-}
+	for_each_property_of_node(con_np, p)
+		of_link_property(con_np, p->name);
 
-static int of_fwnode_add_links(const struct fwnode_handle *fwnode,
-			       struct device *dev)
-{
-	if (unlikely(!is_of_node(fwnode)))
 	return 0;
-
-	return of_link_to_suppliers(dev, to_of_node(fwnode));
 }
 
 const struct fwnode_operations of_fwnode_ops = {

drivers/usb/host/sl811-hcd.c

@@ -1614,12 +1614,18 @@ sl811h_probe(struct platform_device *dev)
 	void __iomem		*addr_reg;
 	void __iomem		*data_reg;
 	int			retval;
-	u8			tmp, ioaddr = 0;
+	u8			tmp, ioaddr;
 	unsigned long		irqflags;
 
 	if (usb_disabled())
 		return -ENODEV;
 
+	/* the chip may be wired for either kind of addressing */
+	addr = platform_get_mem_or_io(dev, 0);
+	data = platform_get_mem_or_io(dev, 1);
+	if (!addr || !data || resource_type(addr) != resource_type(data))
+		return -ENODEV;
+
 	/* basic sanity checks first.  board-specific init logic should
 	 * have initialized these three resources and probably board
 	 * specific platform_data.  we don't probe for IRQs, and do only
@@ -1632,16 +1638,8 @@ sl811h_probe(struct platform_device *dev)
 	irq = ires->start;
 	irqflags = ires->flags & IRQF_TRIGGER_MASK;
 
-	/* the chip may be wired for either kind of addressing */
-	addr = platform_get_resource(dev, IORESOURCE_MEM, 0);
-	data = platform_get_resource(dev, IORESOURCE_MEM, 1);
-	retval = -EBUSY;
-	if (!addr || !data) {
-		addr = platform_get_resource(dev, IORESOURCE_IO, 0);
-		data = platform_get_resource(dev, IORESOURCE_IO, 1);
-		if (!addr || !data)
-			return -ENODEV;
-		ioaddr = 1;
+	ioaddr = resource_type(addr) == IORESOURCE_IO;
+	if (ioaddr) {
 		/*
 		 * NOTE: 64-bit resource->start is getting truncated
 		 * to avoid compiler warning, assuming that ->start

drivers/vfio/platform/vfio_platform.c

@@ -25,19 +25,8 @@ static struct resource *get_platform_resource(struct vfio_platform_device *vdev,
 					      int num)
 {
 	struct platform_device *dev = (struct platform_device *) vdev->opaque;
-	int i;
 
-	for (i = 0; i < dev->num_resources; i++) {
-		struct resource *r = &dev->resource[i];
-
-		if (resource_type(r) & (IORESOURCE_MEM|IORESOURCE_IO)) {
-			if (!num)
-				return r;
-
-			num--;
-		}
-	}
-	return NULL;
+	return platform_get_mem_or_io(dev, num);
 }
 
 static int get_platform_irq(struct vfio_platform_device *vdev, int i)

fs/kernfs/dir.c

@@ -604,8 +604,7 @@ const struct dentry_operations kernfs_dops = {
  */
 struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry)
 {
-	if (dentry->d_sb->s_op == &kernfs_sops &&
-	    !d_really_is_negative(dentry))
+	if (dentry->d_sb->s_op == &kernfs_sops)
 		return kernfs_dentry_node(dentry);
 	return NULL;
 }
@@ -1599,7 +1598,7 @@ int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent,
 	return error;
 }
 
-/* Relationship between s_mode and the DT_xxx types */
+/* Relationship between mode and the DT_xxx types */
 static inline unsigned char dt_type(struct kernfs_node *kn)
 {
 	return (kn->mode >> 12) & 15;

include/linux/acpi.h

@@ -55,7 +55,7 @@ static inline struct fwnode_handle *acpi_alloc_fwnode_static(void)
 	if (!fwnode)
 		return NULL;
 
-	fwnode->ops = &acpi_static_fwnode_ops;
+	fwnode_init(fwnode, &acpi_static_fwnode_ops);
 
 	return fwnode;
 }

include/linux/device.h

@@ -351,19 +351,13 @@ enum dl_dev_state {
  * struct dev_links_info - Device data related to device links.
  * @suppliers: List of links to supplier devices.
  * @consumers: List of links to consumer devices.
- * @needs_suppliers: Hook to global list of devices waiting for suppliers.
- * @defer_hook: Hook to global list of devices that have deferred sync_state or
- *		deferred fw_devlink.
- * @need_for_probe: If needs_suppliers is on a list, this indicates if the
- *		    suppliers are needed for probe or not.
+ * @defer_sync: Hook to global list of devices that have deferred sync_state.
  * @status: Driver status information.
  */
 struct dev_links_info {
 	struct list_head suppliers;
 	struct list_head consumers;
-	struct list_head needs_suppliers;
-	struct list_head defer_hook;
-	bool need_for_probe;
+	struct list_head defer_sync;
 	enum dl_dev_state status;
 };
 

include/linux/device/class.h

@@ -256,6 +256,20 @@ extern void class_destroy(struct class *cls);
 
 /* This is a #define to keep the compiler from merging different
  * instances of the __key variable */
+
+/**
+ * class_create - create a struct class structure
+ * @owner: pointer to the module that is to "own" this struct class
+ * @name: pointer to a string for the name of this class.
+ *
+ * This is used to create a struct class pointer that can then be used
+ * in calls to device_create().
+ *
+ * Returns &struct class pointer on success, or ERR_PTR() on error.
+ *
+ * Note, the pointer created here is to be destroyed when finished by
+ * making a call to class_destroy().
+ */
 #define class_create(owner, name)		\
 ({						\
 	static struct lock_class_key __key;	\

include/linux/fwnode.h

@@ -10,14 +10,32 @@
 #define _LINUX_FWNODE_H_
 
 #include <linux/types.h>
+#include <linux/list.h>
 
 struct fwnode_operations;
 struct device;
 
+/*
+ * fwnode link flags
+ *
+ * LINKS_ADDED: The fwnode has already be parsed to add fwnode links.
+ */
+#define FWNODE_FLAG_LINKS_ADDED		BIT(0)
+
 struct fwnode_handle {
 	struct fwnode_handle *secondary;
 	const struct fwnode_operations *ops;
 	struct device *dev;
+	struct list_head suppliers;
+	struct list_head consumers;
+	u8 flags;
+};
+
+struct fwnode_link {
+	struct fwnode_handle *supplier;
+	struct list_head s_hook;
+	struct fwnode_handle *consumer;
+	struct list_head c_hook;
 };
 
 /**
@@ -68,44 +86,8 @@ struct fwnode_reference_args {
  *			       endpoint node.
  * @graph_get_port_parent: Return the parent node of a port node.
  * @graph_parse_endpoint: Parse endpoint for port and endpoint id.
- * @add_links:	Called after the device corresponding to the fwnode is added
- *		using device_add(). The function is expected to create device
- *		links to all the suppliers of the device that are available at
- *		the time this function is called.  The function must NOT stop
- *		at the first failed device link if other unlinked supplier
- *		devices are present in the system.  This is necessary for the
- *		driver/bus sync_state() callbacks to work correctly.
- *
- *		For example, say Device-C depends on suppliers Device-S1 and
- *		Device-S2 and the dependency is listed in that order in the
- *		firmware.  Say, S1 gets populated from the firmware after
- *		late_initcall_sync().  Say S2 is populated and probed way
- *		before that in device_initcall(). When C is populated, if this
- *		add_links() function doesn't continue past a "failed linking to
- *		S1" and continue linking C to S2, then S2 will get a
- *		sync_state() callback before C is probed. This is because from
- *		the perspective of S2, C was never a consumer when its
- *		sync_state() evaluation is done. To avoid this, the add_links()
- *		function has to go through all available suppliers of the
- *		device (that corresponds to this fwnode) and link to them
- *		before returning.
- *
- *		If some suppliers are not yet available (indicated by an error
- *		return value), this function will be called again when other
- *		devices are added to allow creating device links to any newly
- *		available suppliers.
- *
- *		Return 0 if device links have been successfully created to all
- *		the known suppliers of this device or if the supplier
- *		information is not known.
- *
- *		Return -ENODEV if the suppliers needed for probing this device
- *		have not been registered yet (because device links can only be
- *		created to devices registered with the driver core).
- *
- *		Return -EAGAIN if some of the suppliers of this device have not
- *		been registered yet, but none of those suppliers are necessary
- *		for probing the device.
+ * @add_links:	Create fwnode links to all the suppliers of the fwnode. Return
+ *		zero on success, a negative error code otherwise.
  */
 struct fwnode_operations {
 	struct fwnode_handle *(*get)(struct fwnode_handle *fwnode);
@@ -145,8 +127,7 @@ struct fwnode_operations {
 	(*graph_get_port_parent)(struct fwnode_handle *fwnode);
 	int (*graph_parse_endpoint)(const struct fwnode_handle *fwnode,
 				    struct fwnode_endpoint *endpoint);
-	int (*add_links)(const struct fwnode_handle *fwnode,
-			 struct device *dev);
+	int (*add_links)(struct fwnode_handle *fwnode);
 };
 
 #define fwnode_has_op(fwnode, op)				\
@@ -170,8 +151,16 @@ struct fwnode_operations {
 	} while (false)
 #define get_dev_from_fwnode(fwnode)	get_device((fwnode)->dev)
 
+static inline void fwnode_init(struct fwnode_handle *fwnode,
+			       const struct fwnode_operations *ops)
+{
+	fwnode->ops = ops;
+	INIT_LIST_HEAD(&fwnode->consumers);
+	INIT_LIST_HEAD(&fwnode->suppliers);
+}
+
 extern u32 fw_devlink_get_flags(void);
-void fw_devlink_pause(void);
-void fw_devlink_resume(void);
+int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup);
+void fwnode_links_purge(struct fwnode_handle *fwnode);
 
 #endif

include/linux/kernfs.h

@@ -116,7 +116,7 @@ struct kernfs_elem_attr {
  * kernfs node is represented by single kernfs_node.  Most fields are
  * private to kernfs and shouldn't be accessed directly by kernfs users.
  *
- * As long as s_count reference is held, the kernfs_node itself is
+ * As long as count reference is held, the kernfs_node itself is
  * accessible.  Dereferencing elem or any other outer entity requires
  * active reference.
  */

include/linux/of.h

@@ -108,7 +108,7 @@ static inline void of_node_init(struct device_node *node)
 #if defined(CONFIG_OF_KOBJ)
 	kobject_init(&node->kobj, &of_node_ktype);
 #endif
-	node->fwnode.ops = &of_fwnode_ops;
+	fwnode_init(&node->fwnode, &of_fwnode_ops);
 }
 
 #if defined(CONFIG_OF_KOBJ)
@@ -1307,6 +1307,7 @@ static inline int of_get_available_child_count(const struct device_node *np)
 #define _OF_DECLARE(table, name, compat, fn, fn_type)			\
 	static const struct of_device_id __of_table_##name		\
 		__used __section("__" #table "_of_table")		\
+		__aligned(__alignof__(struct of_device_id))		\
 		 = { .compatible = compat,				\
 		     .data = (fn == (fn_type)NULL) ? fn : fn  }
 #else

include/linux/platform_device.h

@@ -52,6 +52,9 @@ extern struct device platform_bus;
 
 extern struct resource *platform_get_resource(struct platform_device *,
 					      unsigned int, unsigned int);
+extern struct resource *platform_get_mem_or_io(struct platform_device *,
+					       unsigned int);
+
 extern struct device *
 platform_find_device_by_driver(struct device *start,
 			       const struct device_driver *drv);

include/linux/property.h

@@ -85,9 +85,12 @@ const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode);
 struct fwnode_handle *fwnode_get_parent(const struct fwnode_handle *fwnode);
 struct fwnode_handle *fwnode_get_next_parent(
 	struct fwnode_handle *fwnode);
+struct device *fwnode_get_next_parent_dev(struct fwnode_handle *fwnode);
 unsigned int fwnode_count_parents(const struct fwnode_handle *fwn);
 struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwn,
 					    unsigned int depth);
+bool fwnode_is_ancestor_of(struct fwnode_handle *test_ancestor,
+				  struct fwnode_handle *test_child);
 struct fwnode_handle *fwnode_get_next_child_node(
 	const struct fwnode_handle *fwnode, struct fwnode_handle *child);
 struct fwnode_handle *fwnode_get_next_available_child_node(

kernel/irq/irqdomain.c

@@ -100,7 +100,7 @@ struct fwnode_handle *__irq_domain_alloc_fwnode(unsigned int type, int id,
 	fwid->type = type;
 	fwid->name = n;
 	fwid->pa = pa;
-	fwid->fwnode.ops = &irqchip_fwnode_ops;
+	fwnode_init(&fwid->fwnode, &irqchip_fwnode_ops);
 	return &fwid->fwnode;
 }
 EXPORT_SYMBOL_GPL(__irq_domain_alloc_fwnode);

lib/dynamic_debug.c

@@ -561,9 +561,14 @@ static int ddebug_exec_queries(char *query, const char *modname)
 int dynamic_debug_exec_queries(const char *query, const char *modname)
 {
 	int rc;
-	char *qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL);
+	char *qry; /* writable copy of query */
 
-	if (!query)
+	if (!query) {
+		pr_err("non-null query/command string expected\n");
+		return -EINVAL;
+	}
+	qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL);
+	if (!qry)
 		return -ENOMEM;
 
 	rc = ddebug_exec_queries(qry, modname);