Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux

Pull device tree updates from Grant Likely:
"The branch contains the following device tree changes the v3.17 merge
window:

Group changes to the device tree. In preparation for adding device
tree overlay support, OF_DYNAMIC is reworked so that a set of device
tree changes can be prepared and applied to the tree all at once.
OF_RECONFIG notifiers see the most significant change here so that
users always get a consistent view of the tree. Notifiers generation
is moved from before a change to after it, and notifiers for a group
of changes are emitted after the entire block of changes have been
applied

Automatic console selection from DT. Console drivers can now use
of_console_check() to see if the device node is specified as a console
device. If so then it gets added as a preferred console. UART
devices get this support automatically when uart_add_one_port() is
called.

DT unit tests no longer depend on pre-loaded data in the device tree.
Data is loaded dynamically at the start of unit tests, and then
unloaded again when the tests have completed.

Also contains a few bugfixes for reserved regions and early memory
setup"

* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux: (21 commits)
of: Fixing OF Selftest build error
drivers: of: add automated assignment of reserved regions to client devices
of: Use proper types for checking memory overflow
of: typo fix in __of_prop_dup()
Adding selftest testdata dynamically into live tree
of: Add todo tasklist for Devicetree
of: Transactional DT support.
of: Reorder device tree changes and notifiers
of: Move dynamic node fixups out of powerpc and into common code
of: Make sure attached nodes don't carry along extra children
of: Make devicetree sysfs update functions consistent.
of: Create unlocked versions of node and property add/remove functions
OF: Utility helper functions for dynamic nodes
of: Move CONFIG_OF_DYNAMIC code into a separate file
of: rename of_aliases_mutex to just of_mutex
of/platform: Fix of_platform_device_destroy iteration of devices
of: Migrate of_find_node_by_name() users to for_each_node_by_name()
tty: Update hypervisor tty drivers to use core stdout parsing code.
arm/versatile: Add the uart as the stdout device.
of: Enable console on serial ports specified by /chosen/stdout-path
...

Documentation/devicetree/changesets.txt

···
+A DT changeset is a method which allows one to apply changes
+in the live tree in such a way that either the full set of changes
+will be applied, or none of them will be. If an error occurs partway
+through applying the changeset, then the tree will be rolled back to the
+previous state. A changeset can also be removed after it has been
+applied.
+
+When a changeset is applied, all of the changes get applied to the tree
+at once before emitting OF_RECONFIG notifiers. This is so that the
+receiver sees a complete and consistent state of the tree when it
+receives the notifier.
+
+The sequence of a changeset is as follows.
+
+1. of_changeset_init() - initializes a changeset
+
+2. A number of DT tree change calls, of_changeset_attach_node(),
+of_changeset_detach_node(), of_changeset_add_property(),
+of_changeset_remove_property, of_changeset_update_property() to prepare
+a set of changes. No changes to the active tree are made at this point.
+All the change operations are recorded in the of_changeset 'entries'
+list.
+
+3. mutex_lock(of_mutex) - starts a changeset; The global of_mutex
+ensures there can only be one editor at a time.
+
+4. of_changeset_apply() - Apply the changes to the tree. Either the
+entire changeset will get applied, or if there is an error the tree will
+be restored to the previous state
+
+5. mutex_unlock(of_mutex) - All operations complete, release the mutex
+
+If a successfully applied changeset needs to be removed, it can be done
+with the following sequence.
+
+1. mutex_lock(of_mutex)
+
+2. of_changeset_revert()
+
+3. mutex_unlock(of_mutex)

Documentation/devicetree/todo.txt

···
+Todo list for devicetree:
+
+=== General structure ===
+- Switch from custom lists to (h)list_head for nodes and properties structure
+- Remove of_allnodes list and iterate using list of child nodes alone
+
+=== CONFIG_OF_DYNAMIC ===
+- Switch to RCU for tree updates and get rid of global spinlock
+- Document node lifecycle for CONFIG_OF_DYNAMIC
+- Always set ->full_name at of_attach_node() time
+- pseries: Get rid of open-coded tree modification from arch/powerpc/platforms/pseries/dlpar.c

arch/arm/boot/dts/versatile-ab.dts

···
 		i2c0 = &i2c0;
 	};
 
+	chosen {
+		stdout-path = &uart0;
+	};
+
 	memory {
 		reg = <0x0 0x08000000>;
 	};

arch/arm/boot/dts/versatile-pb.dts

···
 		};
 	};
 };
-
-#include <testcases.dtsi>

arch/powerpc/kernel/prom.c

···
 }
 EXPORT_SYMBOL(cpu_to_chip_id);
 
-#ifdef CONFIG_PPC_PSERIES
-/*
- * Fix up the uninitialized fields in a new device node:
- * name, type and pci-specific fields
- */
-
-static int of_finish_dynamic_node(struct device_node *node)
-{
-	struct device_node *parent = of_get_parent(node);
-	int err = 0;
-	const phandle *ibm_phandle;
-
-	node->name = of_get_property(node, "name", NULL);
-	node->type = of_get_property(node, "device_type", NULL);
-
-	if (!node->name)
-		node->name = "<NULL>";
-	if (!node->type)
-		node->type = "<NULL>";
-
-	if (!parent) {
-		err = -ENODEV;
-		goto out;
-	}
-
-	/* We don't support that function on PowerMac, at least
-	 * not yet
-	 */
-	if (machine_is(powermac))
-		return -ENODEV;
-
-	/* fix up new node's phandle field */
-	if ((ibm_phandle = of_get_property(node, "ibm,phandle", NULL)))
-		node->phandle = *ibm_phandle;
-
-out:
-	of_node_put(parent);
-	return err;
-}
-
-static int prom_reconfig_notifier(struct notifier_block *nb,
-				  unsigned long action, void *node)
-{
-	int err;
-
-	switch (action) {
-	case OF_RECONFIG_ATTACH_NODE:
-		err = of_finish_dynamic_node(node);
-		if (err < 0)
-			printk(KERN_ERR "finish_node returned %d\n", err);
-		break;
-	default:
-		err = 0;
-		break;
-	}
-	return notifier_from_errno(err);
-}
-
-static struct notifier_block prom_reconfig_nb = {
-	.notifier_call = prom_reconfig_notifier,
-	.priority = 10, /* This one needs to run first */
-};
-
-static int __init prom_reconfig_setup(void)
-{
-	return of_reconfig_notifier_register(&prom_reconfig_nb);
-}
-__initcall(prom_reconfig_setup);
-#endif
-
 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
 {
 	return (int)phys_id == get_hard_smp_processor_id(cpu);

arch/powerpc/platforms/powermac/feature.c

···
 		/* Enable GMAC for now for PCI probing. It will be disabled
 		 * later on after PCI probe
 		 */
-		np = of_find_node_by_name(NULL, "ethernet");
-		while(np) {
+		for_each_node_by_name(np, "ethernet")
 			if (of_device_is_compatible(np, "K2-GMAC"))
 				g5_gmac_enable(np, 0, 1);
-			np = of_find_node_by_name(np, "ethernet");
-		}
 
 		/* Enable FW before PCI probe. Will be disabled later on
 		 * Note: We should have a batter way to check that we are
 		 * dealing with uninorth internal cell and not a PCI cell
 		 * on the external PCI. The code below works though.
 		 */
-		np = of_find_node_by_name(NULL, "firewire");
-		while(np) {
+		for_each_node_by_name(np, "firewire") {
 			if (of_device_is_compatible(np, "pci106b,5811")) {
 				macio_chips[0].flags |= MACIO_FLAG_FW_SUPPORTED;
 				g5_fw_enable(np, 0, 1);
 			}
-			np = of_find_node_by_name(np, "firewire");
 		}
 	}
 #else /* CONFIG_PPC64 */
···
 		/* Enable GMAC for now for PCI probing. It will be disabled
 		 * later on after PCI probe
 		 */
-		np = of_find_node_by_name(NULL, "ethernet");
-		while(np) {
+		for_each_node_by_name(np, "ethernet") {
 			if (np->parent
 			    && of_device_is_compatible(np->parent, "uni-north")
 			    && of_device_is_compatible(np, "gmac"))
 				core99_gmac_enable(np, 0, 1);
-			np = of_find_node_by_name(np, "ethernet");
 		}
 
 		/* Enable FW before PCI probe. Will be disabled later on
···
 		 * dealing with uninorth internal cell and not a PCI cell
 		 * on the external PCI. The code below works though.
 		 */
-		np = of_find_node_by_name(NULL, "firewire");
-		while(np) {
+		for_each_node_by_name(np, "firewire") {
 			if (np->parent
 			    && of_device_is_compatible(np->parent, "uni-north")
 			    && (of_device_is_compatible(np, "pci106b,18") ||
···
 				macio_chips[0].flags |= MACIO_FLAG_FW_SUPPORTED;
 				core99_firewire_enable(np, 0, 1);
 			}
-			np = of_find_node_by_name(np, "firewire");
 		}
 
 		/* Enable ATA-100 before PCI probe. */
 		np = of_find_node_by_name(NULL, "ata-6");
-		while(np) {
+		for_each_node_by_name(np, "ata-6") {
 			if (np->parent
 			    && of_device_is_compatible(np->parent, "uni-north")
 			    && of_device_is_compatible(np, "kauai-ata")) {
 				core99_ata100_enable(np, 1);
 			}
-			np = of_find_node_by_name(np, "ata-6");
 		}
 
 		/* Switch airport off */

arch/powerpc/platforms/powermac/pci.c

···
 {
 	struct device_node *nec;
 
-	for (nec = NULL; (nec = of_find_node_by_name(nec, "usb")) != NULL;) {
+	for_each_node_by_name(nec, "usb") {
 		struct pci_controller *hose;
 		u32 data;
 		const u32 *prop;

arch/powerpc/platforms/powermac/smp.c

···
 	int ok;
 
 	/* Look for the clock chip */
-	while ((cc = of_find_node_by_name(cc, "i2c-hwclock")) != NULL) {
+	for_each_node_by_name(cc, "i2c-hwclock") {
 		p = of_get_parent(cc);
 		ok = p && of_device_is_compatible(p, "uni-n-i2c");
 		of_node_put(p);

arch/powerpc/platforms/powermac/udbg_adb.c

···
 	 * of type "adb". If not, we return a failure, but we keep the
 	 * bext output set for now
 	 */
-	for (np = NULL; (np = of_find_node_by_name(np, "keyboard")) != NULL;) {
+	for_each_node_by_name(np, "keyboard") {
 		struct device_node *parent = of_get_parent(np);
 		int found = (parent && strcmp(parent->type, "adb") == 0);
 		of_node_put(parent);

arch/powerpc/platforms/pseries/hotplug-memory.c

···
 	if (!memblock_size)
 		return -EINVAL;
 
-	p = (u32 *)of_get_property(pr->dn, "ibm,dynamic-memory", NULL);
+	p = (u32 *) pr->old_prop->value;
 	if (!p)
 		return -EINVAL;
 

arch/powerpc/platforms/pseries/setup.c

···
 	struct device_node *np;
 	const char *typep;
 
-	for (np = NULL; (np = of_find_node_by_name(np,
-						   "interrupt-controller"));) {
+	for_each_node_by_name(np, "interrupt-controller") {
 		typep = of_get_property(np, "compatible", NULL);
 		if (strstr(typep, "open-pic")) {
 			pSeries_mpic_node = of_node_get(np);

drivers/cpufreq/pmac64-cpufreq.c

···
 	}
 
 	/* Lookup the i2c hwclock */
-	for (hwclock = NULL;
-	     (hwclock = of_find_node_by_name(hwclock, "i2c-hwclock")) != NULL;){
+	for_each_node_by_name(hwclock, "i2c-hwclock") {
 		const char *loc = of_get_property(hwclock,
 				"hwctrl-location", NULL);
 		if (loc == NULL)

drivers/crypto/nx/nx-842.c

···
 		goto error_out;
 	}
 
-	/* Set ptr to new property if provided */
-	if (new_prop) {
-		/* Single property */
-		if (!strncmp(new_prop->name, "status", new_prop->length)) {
-			status = new_prop;
-
-		} else if (!strncmp(new_prop->name, "ibm,max-sg-len",
-					new_prop->length)) {
-			maxsglen = new_prop;
-
-		} else if (!strncmp(new_prop->name, "ibm,max-sync-cop",
-					new_prop->length)) {
-			maxsyncop = new_prop;
-
-		} else {
-			/*
-			 * Skip the update, the property being updated
-			 * has no impact.
-			 */
-			goto out;
-		}
-	}
+	/*
+	 * If this is a property update, there are only certain properties that
+	 * we care about. Bail if it isn't in the below list
+	 */
+	if (new_prop && (strncmp(new_prop->name, "status", new_prop->length) ||
+		         strncmp(new_prop->name, "ibm,max-sg-len", new_prop->length) ||
+		         strncmp(new_prop->name, "ibm,max-sync-cop", new_prop->length)))
+		goto out;
 
 	/* Perform property updates */
 	ret = nx842_OF_upd_status(new_devdata, status);

drivers/edac/cell_edac.c

···
 	int				j;
 	u32				nr_pages;
 
-	for (np = NULL;
-	     (np = of_find_node_by_name(np, "memory")) != NULL;) {
+	for_each_node_by_name(np, "memory") {
 		struct resource r;
 
 		/* We "know" that the Cell firmware only creates one entry

drivers/of/Kconfig

···
 
 config OF_SELFTEST
 	bool "Device Tree Runtime self tests"
-	depends on OF_IRQ
+	depends on OF_IRQ && OF_EARLY_FLATTREE
+	select OF_DYNAMIC
 	help
 	  This option builds in test cases for the device tree infrastructure
 	  that are executed once at boot time, and the results dumped to the

drivers/of/Makefile

···
 obj-y = base.o device.o platform.o
+obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
 obj-$(CONFIG_OF_FLATTREE) += fdt.o
 obj-$(CONFIG_OF_EARLY_FLATTREE) += fdt_address.o
 obj-$(CONFIG_OF_PROMTREE) += pdt.o
 obj-$(CONFIG_OF_ADDRESS)  += address.o
 obj-$(CONFIG_OF_IRQ)    += irq.o
 obj-$(CONFIG_OF_NET)	+= of_net.o
-obj-$(CONFIG_OF_SELFTEST) += selftest.o
+obj-$(CONFIG_OF_SELFTEST) += of_selftest.o
+of_selftest-objs := selftest.o testcase-data/testcases.dtb.o
 obj-$(CONFIG_OF_MDIO)	+= of_mdio.o
 obj-$(CONFIG_OF_PCI)	+= of_pci.o
 obj-$(CONFIG_OF_PCI_IRQ)  += of_pci_irq.o

drivers/of/base.c

···
  *      as published by the Free Software Foundation; either version
  *      2 of the License, or (at your option) any later version.
  */
+#include <linux/console.h>
 #include <linux/ctype.h>
 #include <linux/cpu.h>
 #include <linux/module.h>
···
 EXPORT_SYMBOL(of_allnodes);
 struct device_node *of_chosen;
 struct device_node *of_aliases;
-static struct device_node *of_stdout;
+struct device_node *of_stdout;
 
-static struct kset *of_kset;
+struct kset *of_kset;
 
 /*
- * Used to protect the of_aliases; but also overloaded to hold off addition of
- * nodes to sysfs
+ * Used to protect the of_aliases, to hold off addition of nodes to sysfs.
+ * This mutex must be held whenever modifications are being made to the
+ * device tree. The of_{attach,detach}_node() and
+ * of_{add,remove,update}_property() helpers make sure this happens.
  */
-DEFINE_MUTEX(of_aliases_mutex);
+DEFINE_MUTEX(of_mutex);
 
 /* use when traversing tree through the allnext, child, sibling,
  * or parent members of struct device_node.
···
 }
 #endif
 
-#if defined(CONFIG_OF_DYNAMIC)
-/**
- *	of_node_get - Increment refcount of a node
- *	@node:	Node to inc refcount, NULL is supported to
- *		simplify writing of callers
- *
- *	Returns node.
- */
-struct device_node *of_node_get(struct device_node *node)
-{
-	if (node)
-		kobject_get(&node->kobj);
-	return node;
-}
-EXPORT_SYMBOL(of_node_get);
-
-static inline struct device_node *kobj_to_device_node(struct kobject *kobj)
-{
-	return container_of(kobj, struct device_node, kobj);
-}
-
-/**
- *	of_node_release - release a dynamically allocated node
- *	@kref:  kref element of the node to be released
- *
- *	In of_node_put() this function is passed to kref_put()
- *	as the destructor.
- */
-static void of_node_release(struct kobject *kobj)
-{
-	struct device_node *node = kobj_to_device_node(kobj);
-	struct property *prop = node->properties;
-
-	/* We should never be releasing nodes that haven't been detached. */
-	if (!of_node_check_flag(node, OF_DETACHED)) {
-		pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
-		dump_stack();
-		return;
-	}
-
-	if (!of_node_check_flag(node, OF_DYNAMIC))
-		return;
-
-	while (prop) {
-		struct property *next = prop->next;
-		kfree(prop->name);
-		kfree(prop->value);
-		kfree(prop);
-		prop = next;
-
-		if (!prop) {
-			prop = node->deadprops;
-			node->deadprops = NULL;
-		}
-	}
-	kfree(node->full_name);
-	kfree(node->data);
-	kfree(node);
-}
-
-/**
- *	of_node_put - Decrement refcount of a node
- *	@node:	Node to dec refcount, NULL is supported to
- *		simplify writing of callers
- *
- */
-void of_node_put(struct device_node *node)
-{
-	if (node)
-		kobject_put(&node->kobj);
-}
-EXPORT_SYMBOL(of_node_put);
-#else
+#ifndef CONFIG_OF_DYNAMIC
 static void of_node_release(struct kobject *kobj)
 {
 	/* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
···
 	return name;
 }
 
-static int __of_add_property_sysfs(struct device_node *np, struct property *pp)
+int __of_add_property_sysfs(struct device_node *np, struct property *pp)
 {
 	int rc;
 
 	/* Important: Don't leak passwords */
 	bool secure = strncmp(pp->name, "security-", 9) == 0;
+
+	if (!of_kset || !of_node_is_attached(np))
+		return 0;
 
 	sysfs_bin_attr_init(&pp->attr);
 	pp->attr.attr.name = safe_name(&np->kobj, pp->name);
···
 	return rc;
 }
 
-static int __of_node_add(struct device_node *np)
+int __of_attach_node_sysfs(struct device_node *np)
 {
 	const char *name;
 	struct property *pp;
 	int rc;
+
+	if (!of_kset)
+		return 0;
 
 	np->kobj.kset = of_kset;
 	if (!np->parent) {
···
 	return 0;
 }
 
-int of_node_add(struct device_node *np)
-{
-	int rc = 0;
-
-	BUG_ON(!of_node_is_initialized(np));
-
-	/*
-	 * Grab the mutex here so that in a race condition between of_init() and
-	 * of_node_add(), node addition will still be consistent.
-	 */
-	mutex_lock(&of_aliases_mutex);
-	if (of_kset)
-		rc = __of_node_add(np);
-	else
-		/* This scenario may be perfectly valid, but report it anyway */
-		pr_info("of_node_add(%s) before of_init()\n", np->full_name);
-	mutex_unlock(&of_aliases_mutex);
-	return rc;
-}
-
-#if defined(CONFIG_OF_DYNAMIC)
-static void of_node_remove(struct device_node *np)
-{
-	struct property *pp;
-
-	BUG_ON(!of_node_is_initialized(np));
-
-	/* only remove properties if on sysfs */
-	if (of_node_is_attached(np)) {
-		for_each_property_of_node(np, pp)
-			sysfs_remove_bin_file(&np->kobj, &pp->attr);
-		kobject_del(&np->kobj);
-	}
-
-	/* finally remove the kobj_init ref */
-	of_node_put(np);
-}
-#endif
-
 static int __init of_init(void)
 {
 	struct device_node *np;
 
 	/* Create the kset, and register existing nodes */
-	mutex_lock(&of_aliases_mutex);
+	mutex_lock(&of_mutex);
 	of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj);
 	if (!of_kset) {
-		mutex_unlock(&of_aliases_mutex);
+		mutex_unlock(&of_mutex);
 		return -ENOMEM;
 	}
 	for_each_of_allnodes(np)
-		__of_node_add(np);
-	mutex_unlock(&of_aliases_mutex);
+		__of_attach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
 
 	/* Symlink in /proc as required by userspace ABI */
 	if (of_allnodes)
···
  * Find a property with a given name for a given node
  * and return the value.
  */
-static const void *__of_get_property(const struct device_node *np,
-				     const char *name, int *lenp)
+const void *__of_get_property(const struct device_node *np,
+			      const char *name, int *lenp)
 {
 	struct property *pp = __of_find_property(np, name, lenp);
 
···
 }
 EXPORT_SYMBOL(of_count_phandle_with_args);
 
-#if defined(CONFIG_OF_DYNAMIC)
-static int of_property_notify(int action, struct device_node *np,
-			      struct property *prop)
-{
-	struct of_prop_reconfig pr;
-
-	/* only call notifiers if the node is attached */
-	if (!of_node_is_attached(np))
-		return 0;
-
-	pr.dn = np;
-	pr.prop = prop;
-	return of_reconfig_notify(action, &pr);
-}
-#else
-static int of_property_notify(int action, struct device_node *np,
-			      struct property *prop)
-{
-	return 0;
-}
-#endif
-
 /**
  * __of_add_property - Add a property to a node without lock operations
  */
-static int __of_add_property(struct device_node *np, struct property *prop)
+int __of_add_property(struct device_node *np, struct property *prop)
 {
 	struct property **next;
 
···
 	unsigned long flags;
 	int rc;
 
-	rc = of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop);
-	if (rc)
-		return rc;
+	mutex_lock(&of_mutex);
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
 	rc = __of_add_property(np, prop);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
-	if (rc)
-		return rc;
 
-	if (of_node_is_attached(np))
+	if (!rc)
 		__of_add_property_sysfs(np, prop);
 
+	mutex_unlock(&of_mutex);
+
+	if (!rc)
+		of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL);
+
 	return rc;
+}
+
+int __of_remove_property(struct device_node *np, struct property *prop)
+{
+	struct property **next;
+
+	for (next = &np->properties; *next; next = &(*next)->next) {
+		if (*next == prop)
+			break;
+	}
+	if (*next == NULL)
+		return -ENODEV;
+
+	/* found the node */
+	*next = prop->next;
+	prop->next = np->deadprops;
+	np->deadprops = prop;
+
+	return 0;
+}
+
+void __of_remove_property_sysfs(struct device_node *np, struct property *prop)
+{
+	/* at early boot, bail here and defer setup to of_init() */
+	if (of_kset && of_node_is_attached(np))
+		sysfs_remove_bin_file(&np->kobj, &prop->attr);
 }
 
 /**
···
  */
 int of_remove_property(struct device_node *np, struct property *prop)
 {
-	struct property **next;
 	unsigned long flags;
-	int found = 0;
 	int rc;
 
-	rc = of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop);
-	if (rc)
-		return rc;
+	mutex_lock(&of_mutex);
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	next = &np->properties;
-	while (*next) {
-		if (*next == prop) {
-			/* found the node */
-			*next = prop->next;
-			prop->next = np->deadprops;
-			np->deadprops = prop;
-			found = 1;
-			break;
-		}
-		next = &(*next)->next;
-	}
+	rc = __of_remove_property(np, prop);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
-	if (!found)
-		return -ENODEV;
+	if (!rc)
+		__of_remove_property_sysfs(np, prop);
 
-	/* at early boot, bail hear and defer setup to of_init() */
-	if (!of_kset)
-		return 0;
+	mutex_unlock(&of_mutex);
 
-	sysfs_remove_bin_file(&np->kobj, &prop->attr);
+	if (!rc)
+		of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL);
+
+	return rc;
+}
+
+int __of_update_property(struct device_node *np, struct property *newprop,
+		struct property **oldpropp)
+{
+	struct property **next, *oldprop;
+
+	for (next = &np->properties; *next; next = &(*next)->next) {
+		if (of_prop_cmp((*next)->name, newprop->name) == 0)
+			break;
+	}
+	*oldpropp = oldprop = *next;
+
+	if (oldprop) {
+		/* replace the node */
+		newprop->next = oldprop->next;
+		*next = newprop;
+		oldprop->next = np->deadprops;
+		np->deadprops = oldprop;
+	} else {
+		/* new node */
+		newprop->next = NULL;
+		*next = newprop;
+	}
 
 	return 0;
+}
+
+void __of_update_property_sysfs(struct device_node *np, struct property *newprop,
+		struct property *oldprop)
+{
+	/* At early boot, bail out and defer setup to of_init() */
+	if (!of_kset)
+		return;
+
+	if (oldprop)
+		sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
+	__of_add_property_sysfs(np, newprop);
 }
 
 /*
···
  */
 int of_update_property(struct device_node *np, struct property *newprop)
 {
-	struct property **next, *oldprop;
+	struct property *oldprop;
 	unsigned long flags;
 	int rc;
-
-	rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop);
-	if (rc)
-		return rc;
 
 	if (!newprop->name)
 		return -EINVAL;
 
-	raw_spin_lock_irqsave(&devtree_lock, flags);
-	next = &np->properties;
-	oldprop = __of_find_property(np, newprop->name, NULL);
-	if (!oldprop) {
-		/* add the new node */
-		rc = __of_add_property(np, newprop);
-	} else while (*next) {
-		/* replace the node */
-		if (*next == oldprop) {
-			newprop->next = oldprop->next;
-			*next = newprop;
-			oldprop->next = np->deadprops;
-			np->deadprops = oldprop;
-			break;
-		}
-		next = &(*next)->next;
-	}
-	raw_spin_unlock_irqrestore(&devtree_lock, flags);
-	if (rc)
-		return rc;
-
-	/* At early boot, bail out and defer setup to of_init() */
-	if (!of_kset)
-		return 0;
-
-	/* Update the sysfs attribute */
-	if (oldprop)
-		sysfs_remove_bin_file(&np->kobj, &oldprop->attr);
-	__of_add_property_sysfs(np, newprop);
-
-	return 0;
-}
-
-#if defined(CONFIG_OF_DYNAMIC)
-/*
- * Support for dynamic device trees.
- *
- * On some platforms, the device tree can be manipulated at runtime.
- * The routines in this section support adding, removing and changing
- * device tree nodes.
- */
-
-static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain);
-
-int of_reconfig_notifier_register(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_register(&of_reconfig_chain, nb);
-}
-EXPORT_SYMBOL_GPL(of_reconfig_notifier_register);
-
-int of_reconfig_notifier_unregister(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_unregister(&of_reconfig_chain, nb);
-}
-EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister);
-
-int of_reconfig_notify(unsigned long action, void *p)
-{
-	int rc;
-
-	rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p);
-	return notifier_to_errno(rc);
-}
-
-/**
- * of_attach_node - Plug a device node into the tree and global list.
- */
-int of_attach_node(struct device_node *np)
-{
-	unsigned long flags;
-	int rc;
-
-	rc = of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np);
-	if (rc)
-		return rc;
+	mutex_lock(&of_mutex);
 
 	raw_spin_lock_irqsave(&devtree_lock, flags);
-	np->sibling = np->parent->child;
-	np->allnext = np->parent->allnext;
-	np->parent->allnext = np;
-	np->parent->child = np;
-	of_node_clear_flag(np, OF_DETACHED);
+	rc = __of_update_property(np, newprop, &oldprop);
 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
 
-	of_node_add(np);
-	return 0;
-}
+	if (!rc)
+		__of_update_property_sysfs(np, newprop, oldprop);
 
-/**
- * of_detach_node - "Unplug" a node from the device tree.
- *
- * The caller must hold a reference to the node.  The memory associated with
- * the node is not freed until its refcount goes to zero.
- */
-int of_detach_node(struct device_node *np)
-{
-	struct device_node *parent;
-	unsigned long flags;
-	int rc = 0;
+	mutex_unlock(&of_mutex);
 
-	rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np);
-	if (rc)
-		return rc;
+	if (!rc)
+		of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop);
 
-	raw_spin_lock_irqsave(&devtree_lock, flags);
-
-	if (of_node_check_flag(np, OF_DETACHED)) {
-		/* someone already detached it */
-		raw_spin_unlock_irqrestore(&devtree_lock, flags);
-		return rc;
-	}
-
-	parent = np->parent;
-	if (!parent) {
-		raw_spin_unlock_irqrestore(&devtree_lock, flags);
-		return rc;
-	}
-
-	if (of_allnodes == np)
-		of_allnodes = np->allnext;
-	else {
-		struct device_node *prev;
-		for (prev = of_allnodes;
-		     prev->allnext != np;
-		     prev = prev->allnext)
-			;
-		prev->allnext = np->allnext;
-	}
-
-	if (parent->child == np)
-		parent->child = np->sibling;
-	else {
-		struct device_node *prevsib;
-		for (prevsib = np->parent->child;
-		     prevsib->sibling != np;
-		     prevsib = prevsib->sibling)
-			;
-		prevsib->sibling = np->sibling;
-	}
-
-	of_node_set_flag(np, OF_DETACHED);
-	raw_spin_unlock_irqrestore(&devtree_lock, flags);
-
-	of_node_remove(np);
 	return rc;
 }
-#endif /* defined(CONFIG_OF_DYNAMIC) */
 
 static void of_alias_add(struct alias_prop *ap, struct device_node *np,
 			 int id, const char *stem, int stem_len)
···
 		of_chosen = of_find_node_by_path("/chosen@0");
 
 	if (of_chosen) {
+		/* linux,stdout-path and /aliases/stdout are for legacy compatibility */
 		const char *name = of_get_property(of_chosen, "stdout-path", NULL);
 		if (!name)
 			name = of_get_property(of_chosen, "linux,stdout-path", NULL);
+		if (IS_ENABLED(CONFIG_PPC) && !name)
+			name = of_get_property(of_aliases, "stdout", NULL);
 		if (name)
 			of_stdout = of_find_node_by_path(name);
 	}
···
 	struct alias_prop *app;
 	int id = -ENODEV;
 
-	mutex_lock(&of_aliases_mutex);
+	mutex_lock(&of_mutex);
 	list_for_each_entry(app, &aliases_lookup, link) {
 		if (strcmp(app->stem, stem) != 0)
 			continue;
···
 			break;
 		}
 	}
-	mutex_unlock(&of_aliases_mutex);
+	mutex_unlock(&of_mutex);
 
 	return id;
 }
···
 EXPORT_SYMBOL_GPL(of_prop_next_string);
 
 /**
- * of_device_is_stdout_path - check if a device node matches the
- *                            linux,stdout-path property
+ * of_console_check() - Test and setup console for DT setup
+ * @dn - Pointer to device node
+ * @name - Name to use for preferred console without index. ex. "ttyS"
+ * @index - Index to use for preferred console.
  *
- * Check if this device node matches the linux,stdout-path property
- * in the chosen node. return true if yes, false otherwise.
+ * Check if the given device node matches the stdout-path property in the
+ * /chosen node. If it does then register it as the preferred console and return
+ * TRUE. Otherwise return FALSE.
  */
-int of_device_is_stdout_path(struct device_node *dn)
+bool of_console_check(struct device_node *dn, char *name, int index)
 {
-	if (!of_stdout)
+	if (!dn || dn != of_stdout || console_set_on_cmdline)
 		return false;
-
-	return of_stdout == dn;
+	return add_preferred_console(name, index, NULL);
 }
-EXPORT_SYMBOL_GPL(of_device_is_stdout_path);
+EXPORT_SYMBOL_GPL(of_console_check);
 
 /**
  *	of_find_next_cache_node - Find a node's subsidiary cache

drivers/of/device.c

···
 	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
 
 	seen = 0;
-	mutex_lock(&of_aliases_mutex);
+	mutex_lock(&of_mutex);
 	list_for_each_entry(app, &aliases_lookup, link) {
 		if (dev->of_node == app->np) {
 			add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
···
 			seen++;
 		}
 	}
-	mutex_unlock(&of_aliases_mutex);
+	mutex_unlock(&of_mutex);
 }
 
 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)

drivers/of/dynamic.c

···
+/*
+ * Support for dynamic device trees.
+ *
+ * On some platforms, the device tree can be manipulated at runtime.
+ * The routines in this section support adding, removing and changing
+ * device tree nodes.
+ */
+
+#include <linux/of.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+
+#include "of_private.h"
+
+/**
+ * of_node_get() - Increment refcount of a node
+ * @node:	Node to inc refcount, NULL is supported to simplify writing of
+ *		callers
+ *
+ * Returns node.
+ */
+struct device_node *of_node_get(struct device_node *node)
+{
+	if (node)
+		kobject_get(&node->kobj);
+	return node;
+}
+EXPORT_SYMBOL(of_node_get);
+
+/**
+ * of_node_put() - Decrement refcount of a node
+ * @node:	Node to dec refcount, NULL is supported to simplify writing of
+ *		callers
+ */
+void of_node_put(struct device_node *node)
+{
+	if (node)
+		kobject_put(&node->kobj);
+}
+EXPORT_SYMBOL(of_node_put);
+
+void __of_detach_node_sysfs(struct device_node *np)
+{
+	struct property *pp;
+
+	BUG_ON(!of_node_is_initialized(np));
+	if (!of_kset)
+		return;
+
+	/* only remove properties if on sysfs */
+	if (of_node_is_attached(np)) {
+		for_each_property_of_node(np, pp)
+			sysfs_remove_bin_file(&np->kobj, &pp->attr);
+		kobject_del(&np->kobj);
+	}
+
+	/* finally remove the kobj_init ref */
+	of_node_put(np);
+}
+
+static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain);
+
+int of_reconfig_notifier_register(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&of_reconfig_chain, nb);
+}
+EXPORT_SYMBOL_GPL(of_reconfig_notifier_register);
+
+int of_reconfig_notifier_unregister(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&of_reconfig_chain, nb);
+}
+EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister);
+
+int of_reconfig_notify(unsigned long action, void *p)
+{
+	int rc;
+
+	rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p);
+	return notifier_to_errno(rc);
+}
+
+int of_property_notify(int action, struct device_node *np,
+		       struct property *prop, struct property *oldprop)
+{
+	struct of_prop_reconfig pr;
+
+	/* only call notifiers if the node is attached */
+	if (!of_node_is_attached(np))
+		return 0;
+
+	pr.dn = np;
+	pr.prop = prop;
+	pr.old_prop = oldprop;
+	return of_reconfig_notify(action, &pr);
+}
+
+void __of_attach_node(struct device_node *np)
+{
+	const __be32 *phandle;
+	int sz;
+
+	np->name = __of_get_property(np, "name", NULL) ? : "<NULL>";
+	np->type = __of_get_property(np, "device_type", NULL) ? : "<NULL>";
+
+	phandle = __of_get_property(np, "phandle", &sz);
+	if (!phandle)
+		phandle = __of_get_property(np, "linux,phandle", &sz);
+	if (IS_ENABLED(PPC_PSERIES) && !phandle)
+		phandle = __of_get_property(np, "ibm,phandle", &sz);
+	np->phandle = (phandle && (sz >= 4)) ? be32_to_cpup(phandle) : 0;
+
+	np->child = NULL;
+	np->sibling = np->parent->child;
+	np->allnext = np->parent->allnext;
+	np->parent->allnext = np;
+	np->parent->child = np;
+	of_node_clear_flag(np, OF_DETACHED);
+}
+
+/**
+ * of_attach_node() - Plug a device node into the tree and global list.
+ */
+int of_attach_node(struct device_node *np)
+{
+	unsigned long flags;
+
+	mutex_lock(&of_mutex);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	__of_attach_node(np);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	__of_attach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
+
+	of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np);
+
+	return 0;
+}
+
+void __of_detach_node(struct device_node *np)
+{
+	struct device_node *parent;
+
+	if (WARN_ON(of_node_check_flag(np, OF_DETACHED)))
+		return;
+
+	parent = np->parent;
+	if (WARN_ON(!parent))
+		return;
+
+	if (of_allnodes == np)
+		of_allnodes = np->allnext;
+	else {
+		struct device_node *prev;
+		for (prev = of_allnodes;
+		     prev->allnext != np;
+		     prev = prev->allnext)
+			;
+		prev->allnext = np->allnext;
+	}
+
+	if (parent->child == np)
+		parent->child = np->sibling;
+	else {
+		struct device_node *prevsib;
+		for (prevsib = np->parent->child;
+		     prevsib->sibling != np;
+		     prevsib = prevsib->sibling)
+			;
+		prevsib->sibling = np->sibling;
+	}
+
+	of_node_set_flag(np, OF_DETACHED);
+}
+
+/**
+ * of_detach_node() - "Unplug" a node from the device tree.
+ *
+ * The caller must hold a reference to the node.  The memory associated with
+ * the node is not freed until its refcount goes to zero.
+ */
+int of_detach_node(struct device_node *np)
+{
+	unsigned long flags;
+	int rc = 0;
+
+	mutex_lock(&of_mutex);
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	__of_detach_node(np);
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	__of_detach_node_sysfs(np);
+	mutex_unlock(&of_mutex);
+
+	of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np);
+
+	return rc;
+}
+
+/**
+ * of_node_release() - release a dynamically allocated node
+ * @kref: kref element of the node to be released
+ *
+ * In of_node_put() this function is passed to kref_put() as the destructor.
+ */
+void of_node_release(struct kobject *kobj)
+{
+	struct device_node *node = kobj_to_device_node(kobj);
+	struct property *prop = node->properties;
+
+	/* We should never be releasing nodes that haven't been detached. */
+	if (!of_node_check_flag(node, OF_DETACHED)) {
+		pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
+		dump_stack();
+		return;
+	}
+
+	if (!of_node_check_flag(node, OF_DYNAMIC))
+		return;
+
+	while (prop) {
+		struct property *next = prop->next;
+		kfree(prop->name);
+		kfree(prop->value);
+		kfree(prop);
+		prop = next;
+
+		if (!prop) {
+			prop = node->deadprops;
+			node->deadprops = NULL;
+		}
+	}
+	kfree(node->full_name);
+	kfree(node->data);
+	kfree(node);
+}
+
+/**
+ * __of_prop_dup - Copy a property dynamically.
+ * @prop:	Property to copy
+ * @allocflags:	Allocation flags (typically pass GFP_KERNEL)
+ *
+ * Copy a property by dynamically allocating the memory of both the
+ * property stucture and the property name & contents. The property's
+ * flags have the OF_DYNAMIC bit set so that we can differentiate between
+ * dynamically allocated properties and not.
+ * Returns the newly allocated property or NULL on out of memory error.
+ */
+struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags)
+{
+	struct property *new;
+
+	new = kzalloc(sizeof(*new), allocflags);
+	if (!new)
+		return NULL;
+
+	/*
+	 * NOTE: There is no check for zero length value.
+	 * In case of a boolean property, this will allocate a value
+	 * of zero bytes. We do this to work around the use
+	 * of of_get_property() calls on boolean values.
+	 */
+	new->name = kstrdup(prop->name, allocflags);
+	new->value = kmemdup(prop->value, prop->length, allocflags);
+	new->length = prop->length;
+	if (!new->name || !new->value)
+		goto err_free;
+
+	/* mark the property as dynamic */
+	of_property_set_flag(new, OF_DYNAMIC);
+
+	return new;
+
+ err_free:
+	kfree(new->name);
+	kfree(new->value);
+	kfree(new);
+	return NULL;
+}
+
+/**
+ * __of_node_alloc() - Create an empty device node dynamically.
+ * @full_name:	Full name of the new device node
+ * @allocflags:	Allocation flags (typically pass GFP_KERNEL)
+ *
+ * Create an empty device tree node, suitable for further modification.
+ * The node data are dynamically allocated and all the node flags
+ * have the OF_DYNAMIC & OF_DETACHED bits set.
+ * Returns the newly allocated node or NULL on out of memory error.
+ */
+struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags)
+{
+	struct device_node *node;
+
+	node = kzalloc(sizeof(*node), allocflags);
+	if (!node)
+		return NULL;
+
+	node->full_name = kstrdup(full_name, allocflags);
+	of_node_set_flag(node, OF_DYNAMIC);
+	of_node_set_flag(node, OF_DETACHED);
+	if (!node->full_name)
+		goto err_free;
+
+	of_node_init(node);
+
+	return node;
+
+ err_free:
+	kfree(node->full_name);
+	kfree(node);
+	return NULL;
+}
+
+static void __of_changeset_entry_destroy(struct of_changeset_entry *ce)
+{
+	of_node_put(ce->np);
+	list_del(&ce->node);
+	kfree(ce);
+}
+
+#ifdef DEBUG
+static void __of_changeset_entry_dump(struct of_changeset_entry *ce)
+{
+	switch (ce->action) {
+	case OF_RECONFIG_ADD_PROPERTY:
+		pr_debug("%p: %s %s/%s\n",
+			ce, "ADD_PROPERTY   ", ce->np->full_name,
+			ce->prop->name);
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		pr_debug("%p: %s %s/%s\n",
+			ce, "REMOVE_PROPERTY", ce->np->full_name,
+			ce->prop->name);
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		pr_debug("%p: %s %s/%s\n",
+			ce, "UPDATE_PROPERTY", ce->np->full_name,
+			ce->prop->name);
+		break;
+	case OF_RECONFIG_ATTACH_NODE:
+		pr_debug("%p: %s %s\n",
+			ce, "ATTACH_NODE    ", ce->np->full_name);
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		pr_debug("%p: %s %s\n",
+			ce, "DETACH_NODE    ", ce->np->full_name);
+		break;
+	}
+}
+#else
+static inline void __of_changeset_entry_dump(struct of_changeset_entry *ce)
+{
+	/* empty */
+}
+#endif
+
+static void __of_changeset_entry_invert(struct of_changeset_entry *ce,
+					  struct of_changeset_entry *rce)
+{
+	memcpy(rce, ce, sizeof(*rce));
+
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		rce->action = OF_RECONFIG_DETACH_NODE;
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		rce->action = OF_RECONFIG_ATTACH_NODE;
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		rce->action = OF_RECONFIG_REMOVE_PROPERTY;
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		rce->action = OF_RECONFIG_ADD_PROPERTY;
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		rce->old_prop = ce->prop;
+		rce->prop = ce->old_prop;
+		break;
+	}
+}
+
+static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool revert)
+{
+	struct of_changeset_entry ce_inverted;
+	int ret;
+
+	if (revert) {
+		__of_changeset_entry_invert(ce, &ce_inverted);
+		ce = &ce_inverted;
+	}
+
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+	case OF_RECONFIG_DETACH_NODE:
+		ret = of_reconfig_notify(ce->action, ce->np);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+	case OF_RECONFIG_REMOVE_PROPERTY:
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		ret = of_property_notify(ce->action, ce->np, ce->prop, ce->old_prop);
+		break;
+	default:
+		pr_err("%s: invalid devicetree changeset action: %i\n", __func__,
+			(int)ce->action);
+		return;
+	}
+
+	if (ret)
+		pr_err("%s: notifier error @%s\n", __func__, ce->np->full_name);
+}
+
+static int __of_changeset_entry_apply(struct of_changeset_entry *ce)
+{
+	struct property *old_prop, **propp;
+	unsigned long flags;
+	int ret = 0;
+
+	__of_changeset_entry_dump(ce);
+
+	raw_spin_lock_irqsave(&devtree_lock, flags);
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		__of_attach_node(ce->np);
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		__of_detach_node(ce->np);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		/* If the property is in deadprops then it must be removed */
+		for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) {
+			if (*propp == ce->prop) {
+				*propp = ce->prop->next;
+				ce->prop->next = NULL;
+				break;
+			}
+		}
+
+		ret = __of_add_property(ce->np, ce->prop);
+		if (ret) {
+			pr_err("%s: add_property failed @%s/%s\n",
+				__func__, ce->np->full_name,
+				ce->prop->name);
+			break;
+		}
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		ret = __of_remove_property(ce->np, ce->prop);
+		if (ret) {
+			pr_err("%s: remove_property failed @%s/%s\n",
+				__func__, ce->np->full_name,
+				ce->prop->name);
+			break;
+		}
+		break;
+
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		/* If the property is in deadprops then it must be removed */
+		for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) {
+			if (*propp == ce->prop) {
+				*propp = ce->prop->next;
+				ce->prop->next = NULL;
+				break;
+			}
+		}
+
+		ret = __of_update_property(ce->np, ce->prop, &old_prop);
+		if (ret) {
+			pr_err("%s: update_property failed @%s/%s\n",
+				__func__, ce->np->full_name,
+				ce->prop->name);
+			break;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+	}
+	raw_spin_unlock_irqrestore(&devtree_lock, flags);
+
+	if (ret)
+		return ret;
+
+	switch (ce->action) {
+	case OF_RECONFIG_ATTACH_NODE:
+		__of_attach_node_sysfs(ce->np);
+		break;
+	case OF_RECONFIG_DETACH_NODE:
+		__of_detach_node_sysfs(ce->np);
+		break;
+	case OF_RECONFIG_ADD_PROPERTY:
+		/* ignore duplicate names */
+		__of_add_property_sysfs(ce->np, ce->prop);
+		break;
+	case OF_RECONFIG_REMOVE_PROPERTY:
+		__of_remove_property_sysfs(ce->np, ce->prop);
+		break;
+	case OF_RECONFIG_UPDATE_PROPERTY:
+		__of_update_property_sysfs(ce->np, ce->prop, ce->old_prop);
+		break;
+	}
+
+	return 0;
+}
+
+static inline int __of_changeset_entry_revert(struct of_changeset_entry *ce)
+{
+	struct of_changeset_entry ce_inverted;
+
+	__of_changeset_entry_invert(ce, &ce_inverted);
+	return __of_changeset_entry_apply(&ce_inverted);
+}
+
+/**
+ * of_changeset_init - Initialize a changeset for use
+ *
+ * @ocs:	changeset pointer
+ *
+ * Initialize a changeset structure
+ */
+void of_changeset_init(struct of_changeset *ocs)
+{
+	memset(ocs, 0, sizeof(*ocs));
+	INIT_LIST_HEAD(&ocs->entries);
+}
+
+/**
+ * of_changeset_destroy - Destroy a changeset
+ *
+ * @ocs:	changeset pointer
+ *
+ * Destroys a changeset. Note that if a changeset is applied,
+ * its changes to the tree cannot be reverted.
+ */
+void of_changeset_destroy(struct of_changeset *ocs)
+{
+	struct of_changeset_entry *ce, *cen;
+
+	list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node)
+		__of_changeset_entry_destroy(ce);
+}
+
+/**
+ * of_changeset_apply - Applies a changeset
+ *
+ * @ocs:	changeset pointer
+ *
+ * Applies a changeset to the live tree.
+ * Any side-effects of live tree state changes are applied here on
+ * sucess, like creation/destruction of devices and side-effects
+ * like creation of sysfs properties and directories.
+ * Returns 0 on success, a negative error value in case of an error.
+ * On error the partially applied effects are reverted.
+ */
+int of_changeset_apply(struct of_changeset *ocs)
+{
+	struct of_changeset_entry *ce;
+	int ret;
+
+	/* perform the rest of the work */
+	pr_debug("of_changeset: applying...\n");
+	list_for_each_entry(ce, &ocs->entries, node) {
+		ret = __of_changeset_entry_apply(ce);
+		if (ret) {
+			pr_err("%s: Error applying changeset (%d)\n", __func__, ret);
+			list_for_each_entry_continue_reverse(ce, &ocs->entries, node)
+				__of_changeset_entry_revert(ce);
+			return ret;
+		}
+	}
+	pr_debug("of_changeset: applied, emitting notifiers.\n");
+
+	/* drop the global lock while emitting notifiers */
+	mutex_unlock(&of_mutex);
+	list_for_each_entry(ce, &ocs->entries, node)
+		__of_changeset_entry_notify(ce, 0);
+	mutex_lock(&of_mutex);
+	pr_debug("of_changeset: notifiers sent.\n");
+
+	return 0;
+}
+
+/**
+ * of_changeset_revert - Reverts an applied changeset
+ *
+ * @ocs:	changeset pointer
+ *
+ * Reverts a changeset returning the state of the tree to what it
+ * was before the application.
+ * Any side-effects like creation/destruction of devices and
+ * removal of sysfs properties and directories are applied.
+ * Returns 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_revert(struct of_changeset *ocs)
+{
+	struct of_changeset_entry *ce;
+	int ret;
+
+	pr_debug("of_changeset: reverting...\n");
+	list_for_each_entry_reverse(ce, &ocs->entries, node) {
+		ret = __of_changeset_entry_revert(ce);
+		if (ret) {
+			pr_err("%s: Error reverting changeset (%d)\n", __func__, ret);
+			list_for_each_entry_continue(ce, &ocs->entries, node)
+				__of_changeset_entry_apply(ce);
+			return ret;
+		}
+	}
+	pr_debug("of_changeset: reverted, emitting notifiers.\n");
+
+	/* drop the global lock while emitting notifiers */
+	mutex_unlock(&of_mutex);
+	list_for_each_entry_reverse(ce, &ocs->entries, node)
+		__of_changeset_entry_notify(ce, 1);
+	mutex_lock(&of_mutex);
+	pr_debug("of_changeset: notifiers sent.\n");
+
+	return 0;
+}
+
+/**
+ * of_changeset_action - Perform a changeset action
+ *
+ * @ocs:	changeset pointer
+ * @action:	action to perform
+ * @np:		Pointer to device node
+ * @prop:	Pointer to property
+ *
+ * On action being one of:
+ * + OF_RECONFIG_ATTACH_NODE
+ * + OF_RECONFIG_DETACH_NODE,
+ * + OF_RECONFIG_ADD_PROPERTY
+ * + OF_RECONFIG_REMOVE_PROPERTY,
+ * + OF_RECONFIG_UPDATE_PROPERTY
+ * Returns 0 on success, a negative error value in case of an error.
+ */
+int of_changeset_action(struct of_changeset *ocs, unsigned long action,
+		struct device_node *np, struct property *prop)
+{
+	struct of_changeset_entry *ce;
+
+	ce = kzalloc(sizeof(*ce), GFP_KERNEL);
+	if (!ce) {
+		pr_err("%s: Failed to allocate\n", __func__);
+		return -ENOMEM;
+	}
+	/* get a reference to the node */
+	ce->action = action;
+	ce->np = of_node_get(np);
+	ce->prop = prop;
+
+	if (action == OF_RECONFIG_UPDATE_PROPERTY && prop)
+		ce->old_prop = of_find_property(np, prop->name, NULL);
+
+	/* add it to the list */
+	list_add_tail(&ce->node, &ocs->entries);
+	return 0;
+}

drivers/of/fdt.c

···
 }
 
 #ifdef CONFIG_HAVE_MEMBLOCK
+#define MAX_PHYS_ADDR	((phys_addr_t)~0)
+
 void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
 {
 	const u64 phys_offset = __pa(PAGE_OFFSET);
 	base &= PAGE_MASK;
 	size &= PAGE_MASK;
 
-	if (sizeof(phys_addr_t) < sizeof(u64)) {
-		if (base > ULONG_MAX) {
-			pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
-					base, base + size);
-			return;
-		}
+	if (base > MAX_PHYS_ADDR) {
+		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
+				base, base + size);
+		return;
+	}
 
-		if (base + size > ULONG_MAX) {
-			pr_warning("Ignoring memory range 0x%lx - 0x%llx\n",
-					ULONG_MAX, base + size);
-			size = ULONG_MAX - base;
-		}
+	if (base + size > MAX_PHYS_ADDR) {
+		pr_warning("Ignoring memory range 0x%lx - 0x%llx\n",
+				ULONG_MAX, base + size);
+		size = MAX_PHYS_ADDR - base;
 	}
 
 	if (base + size < phys_offset) {

drivers/of/of_private.h

···
 	char stem[0];
 };
 
-extern struct mutex of_aliases_mutex;
+extern struct mutex of_mutex;
 extern struct list_head aliases_lookup;
+extern struct kset *of_kset;
+
+
+static inline struct device_node *kobj_to_device_node(struct kobject *kobj)
+{
+	return container_of(kobj, struct device_node, kobj);
+}
+
+#if defined(CONFIG_OF_DYNAMIC)
+extern int of_property_notify(int action, struct device_node *np,
+			      struct property *prop, struct property *old_prop);
+extern void of_node_release(struct kobject *kobj);
+#else /* CONFIG_OF_DYNAMIC */
+static inline int of_property_notify(int action, struct device_node *np,
+				     struct property *prop, struct property *old_prop)
+{
+	return 0;
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
+/**
+ * General utilities for working with live trees.
+ *
+ * All functions with two leading underscores operate
+ * without taking node references, so you either have to
+ * own the devtree lock or work on detached trees only.
+ */
+struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags);
+struct device_node *__of_node_alloc(const char *full_name, gfp_t allocflags);
+
+extern const void *__of_get_property(const struct device_node *np,
+				     const char *name, int *lenp);
+extern int __of_add_property(struct device_node *np, struct property *prop);
+extern int __of_add_property_sysfs(struct device_node *np,
+		struct property *prop);
+extern int __of_remove_property(struct device_node *np, struct property *prop);
+extern void __of_remove_property_sysfs(struct device_node *np,
+		struct property *prop);
+extern int __of_update_property(struct device_node *np,
+		struct property *newprop, struct property **oldprop);
+extern void __of_update_property_sysfs(struct device_node *np,
+		struct property *newprop, struct property *oldprop);
+
+extern void __of_attach_node(struct device_node *np);
+extern int __of_attach_node_sysfs(struct device_node *np);
+extern void __of_detach_node(struct device_node *np);
+extern void __of_detach_node_sysfs(struct device_node *np);
+
+/* iterators for transactions, used for overlays */
+/* forward iterator */
+#define for_each_transaction_entry(_oft, _te) \
+	list_for_each_entry(_te, &(_oft)->te_list, node)
+
+/* reverse iterator */
+#define for_each_transaction_entry_reverse(_oft, _te) \
+	list_for_each_entry_reverse(_te, &(_oft)->te_list, node)
+
 #endif /* _LINUX_OF_PRIVATE_H */

drivers/of/of_reserved_mem.c

···
 	for (i = 0; i < reserved_mem_count; i++) {
 		struct reserved_mem *rmem = &reserved_mem[i];
 		unsigned long node = rmem->fdt_node;
+		int len;
+		const __be32 *prop;
 		int err = 0;
+
+		prop = of_get_flat_dt_prop(node, "phandle", &len);
+		if (!prop)
+			prop = of_get_flat_dt_prop(node, "linux,phandle", &len);
+		if (prop)
+			rmem->phandle = of_read_number(prop, len/4);
 
 		if (rmem->size == 0)
 			err = __reserved_mem_alloc_size(node, rmem->name,
···
 		if (err == 0)
 			__reserved_mem_init_node(rmem);
 	}
+}
+
+static inline struct reserved_mem *__find_rmem(struct device_node *node)
+{
+	unsigned int i;
+
+	if (!node->phandle)
+		return NULL;
+
+	for (i = 0; i < reserved_mem_count; i++)
+		if (reserved_mem[i].phandle == node->phandle)
+			return &reserved_mem[i];
+	return NULL;
+}
+
+/**
+ * of_reserved_mem_device_init() - assign reserved memory region to given device
+ *
+ * This function assign memory region pointed by "memory-region" device tree
+ * property to the given device.
+ */
+void of_reserved_mem_device_init(struct device *dev)
+{
+	struct reserved_mem *rmem;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "memory-region", 0);
+	if (!np)
+		return;
+
+	rmem = __find_rmem(np);
+	of_node_put(np);
+
+	if (!rmem || !rmem->ops || !rmem->ops->device_init)
+		return;
+
+	rmem->ops->device_init(rmem, dev);
+	dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
+}
+
+/**
+ * of_reserved_mem_device_release() - release reserved memory device structures
+ *
+ * This function releases structures allocated for memory region handling for
+ * the given device.
+ */
+void of_reserved_mem_device_release(struct device *dev)
+{
+	struct reserved_mem *rmem;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "memory-region", 0);
+	if (!np)
+		return;
+
+	rmem = __find_rmem(np);
+	of_node_put(np);
+
+	if (!rmem || !rmem->ops || !rmem->ops->device_release)
+		return;
+
+	rmem->ops->device_release(rmem, dev);
 }

drivers/of/platform.c

···
 			break;
 		}
 	}
+	of_node_set_flag(bus, OF_POPULATED_BUS);
 	return rc;
 }
 
···
 
 static int of_platform_device_destroy(struct device *dev, void *data)
 {
-	bool *children_left = data;
-
 	/* Do not touch devices not populated from the device tree */
-	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) {
-		*children_left = true;
+	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
 		return 0;
-	}
 
-	/* Recurse, but don't touch this device if it has any children left */
-	if (of_platform_depopulate(dev) != 0) {
-		*children_left = true;
-		return 0;
-	}
+	/* Recurse for any nodes that were treated as busses */
+	if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
+		device_for_each_child(dev, NULL, of_platform_device_destroy);
 
 	if (dev->bus == &platform_bus_type)
 		platform_device_unregister(to_platform_device(dev));
···
 	else if (dev->bus == &amba_bustype)
 		amba_device_unregister(to_amba_device(dev));
 #endif
-	else {
-		*children_left = true;
-		return 0;
-	}
 
 	of_node_clear_flag(dev->of_node, OF_POPULATED);
-
+	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
 	return 0;
 }
 
 /**
  * of_platform_depopulate() - Remove devices populated from device tree
- * @parent: device which childred will be removed
+ * @parent: device which children will be removed
  *
  * Complementary to of_platform_populate(), this function removes children
  * of the given device (and, recurrently, their children) that have been
···
  * Returns 0 when all children devices have been removed or
  * -EBUSY when some children remained.
  */
-int of_platform_depopulate(struct device *parent)
+void of_platform_depopulate(struct device *parent)
 {
-	bool children_left = false;
-
-	device_for_each_child(parent, &children_left,
-			      of_platform_device_destroy);
-
-	return children_left ? -EBUSY : 0;
+	device_for_each_child(parent, NULL, of_platform_device_destroy);
 }
 EXPORT_SYMBOL_GPL(of_platform_depopulate);
 

drivers/of/selftest.c

···
 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_fdt.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
 #include <linux/list.h>
···
 #include <linux/slab.h>
 #include <linux/device.h>
 
+#include "of_private.h"
+
 static struct selftest_results {
 	int passed;
 	int failed;
 } selftest_results;
+
+#define NO_OF_NODES 2
+static struct device_node *nodes[NO_OF_NODES];
+static int last_node_index;
 
 #define selftest(result, fmt, ...) { \
 	if (!(result)) { \
···
 	selftest(rc == -ENODATA, "empty property; rc=%i", rc);
 	rc = of_property_match_string(np, "unterminated-string", "blah");
 	selftest(rc == -EILSEQ, "unterminated string; rc=%i", rc);
+}
+
+#define propcmp(p1, p2) (((p1)->length == (p2)->length) && \
+			(p1)->value && (p2)->value && \
+			!memcmp((p1)->value, (p2)->value, (p1)->length) && \
+			!strcmp((p1)->name, (p2)->name))
+static void __init of_selftest_property_copy(void)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	struct property p1 = { .name = "p1", .length = 0, .value = "" };
+	struct property p2 = { .name = "p2", .length = 5, .value = "abcd" };
+	struct property *new;
+
+	new = __of_prop_dup(&p1, GFP_KERNEL);
+	selftest(new && propcmp(&p1, new), "empty property didn't copy correctly\n");
+	kfree(new->value);
+	kfree(new->name);
+	kfree(new);
+
+	new = __of_prop_dup(&p2, GFP_KERNEL);
+	selftest(new && propcmp(&p2, new), "non-empty property didn't copy correctly\n");
+	kfree(new->value);
+	kfree(new->name);
+	kfree(new);
+#endif
+}
+
+static void __init of_selftest_changeset(void)
+{
+#ifdef CONFIG_OF_DYNAMIC
+	struct property *ppadd, padd = { .name = "prop-add", .length = 0, .value = "" };
+	struct property *ppupdate, pupdate = { .name = "prop-update", .length = 5, .value = "abcd" };
+	struct property *ppremove;
+	struct device_node *n1, *n2, *n21, *nremove, *parent;
+	struct of_changeset chgset;
+
+	of_changeset_init(&chgset);
+	n1 = __of_node_alloc("/testcase-data/changeset/n1", GFP_KERNEL);
+	selftest(n1, "testcase setup failure\n");
+	n2 = __of_node_alloc("/testcase-data/changeset/n2", GFP_KERNEL);
+	selftest(n2, "testcase setup failure\n");
+	n21 = __of_node_alloc("/testcase-data/changeset/n2/n21", GFP_KERNEL);
+	selftest(n21, "testcase setup failure %p\n", n21);
+	nremove = of_find_node_by_path("/testcase-data/changeset/node-remove");
+	selftest(nremove, "testcase setup failure\n");
+	ppadd = __of_prop_dup(&padd, GFP_KERNEL);
+	selftest(ppadd, "testcase setup failure\n");
+	ppupdate = __of_prop_dup(&pupdate, GFP_KERNEL);
+	selftest(ppupdate, "testcase setup failure\n");
+	parent = nremove->parent;
+	n1->parent = parent;
+	n2->parent = parent;
+	n21->parent = n2;
+	n2->child = n21;
+	ppremove = of_find_property(parent, "prop-remove", NULL);
+	selftest(ppremove, "failed to find removal prop");
+
+	of_changeset_init(&chgset);
+	selftest(!of_changeset_attach_node(&chgset, n1), "fail attach n1\n");
+	selftest(!of_changeset_attach_node(&chgset, n2), "fail attach n2\n");
+	selftest(!of_changeset_detach_node(&chgset, nremove), "fail remove node\n");
+	selftest(!of_changeset_attach_node(&chgset, n21), "fail attach n21\n");
+	selftest(!of_changeset_add_property(&chgset, parent, ppadd), "fail add prop\n");
+	selftest(!of_changeset_update_property(&chgset, parent, ppupdate), "fail update prop\n");
+	selftest(!of_changeset_remove_property(&chgset, parent, ppremove), "fail remove prop\n");
+	mutex_lock(&of_mutex);
+	selftest(!of_changeset_apply(&chgset), "apply failed\n");
+	mutex_unlock(&of_mutex);
+
+	mutex_lock(&of_mutex);
+	selftest(!of_changeset_revert(&chgset), "revert failed\n");
+	mutex_unlock(&of_mutex);
+
+	of_changeset_destroy(&chgset);
+#endif
 }
 
 static void __init of_selftest_parse_interrupts(void)
···
 	}
 }
 
+/**
+ *	update_node_properties - adds the properties
+ *	of np into dup node (present in live tree) and
+ *	updates parent of children of np to dup.
+ *
+ *	@np:	node already present in live tree
+ *	@dup:	node present in live tree to be updated
+ */
+static void update_node_properties(struct device_node *np,
+					struct device_node *dup)
+{
+	struct property *prop;
+	struct device_node *child;
+
+	for_each_property_of_node(np, prop)
+		of_add_property(dup, prop);
+
+	for_each_child_of_node(np, child)
+		child->parent = dup;
+}
+
+/**
+ *	attach_node_and_children - attaches nodes
+ *	and its children to live tree
+ *
+ *	@np:	Node to attach to live tree
+ */
+static int attach_node_and_children(struct device_node *np)
+{
+	struct device_node *next, *root = np, *dup;
+
+	if (!np) {
+		pr_warn("%s: No tree to attach; not running tests\n",
+			__func__);
+		return -ENODATA;
+	}
+
+
+	/* skip root node */
+	np = np->child;
+	/* storing a copy in temporary node */
+	dup = np;
+
+	while (dup) {
+		nodes[last_node_index++] = dup;
+		dup = dup->sibling;
+	}
+	dup = NULL;
+
+	while (np) {
+		next = np->allnext;
+		dup = of_find_node_by_path(np->full_name);
+		if (dup)
+			update_node_properties(np, dup);
+		else {
+			np->child = NULL;
+			if (np->parent == root)
+				np->parent = of_allnodes;
+			of_attach_node(np);
+		}
+		np = next;
+	}
+
+	return 0;
+}
+
+/**
+ *	selftest_data_add - Reads, copies data from
+ *	linked tree and attaches it to the live tree
+ */
+static int __init selftest_data_add(void)
+{
+	void *selftest_data;
+	struct device_node *selftest_data_node;
+	extern uint8_t __dtb_testcases_begin[];
+	extern uint8_t __dtb_testcases_end[];
+	const int size = __dtb_testcases_end - __dtb_testcases_begin;
+
+	if (!size || !of_allnodes) {
+		pr_warn("%s: No testcase data to attach; not running tests\n",
+			__func__);
+		return -ENODATA;
+	}
+
+	/* creating copy */
+	selftest_data = kmemdup(__dtb_testcases_begin, size, GFP_KERNEL);
+
+	if (!selftest_data) {
+		pr_warn("%s: Failed to allocate memory for selftest_data; "
+			"not running tests\n", __func__);
+		return -ENOMEM;
+	}
+	of_fdt_unflatten_tree(selftest_data, &selftest_data_node);
+
+	/* attach the sub-tree to live tree */
+	return attach_node_and_children(selftest_data_node);
+}
+
+/**
+ *	detach_node_and_children - detaches node
+ *	and its children from live tree
+ *
+ *	@np:	Node to detach from live tree
+ */
+static void detach_node_and_children(struct device_node *np)
+{
+	while (np->child)
+		detach_node_and_children(np->child);
+
+	while (np->sibling)
+		detach_node_and_children(np->sibling);
+
+	of_detach_node(np);
+}
+
+/**
+ *	selftest_data_remove - removes the selftest data
+ *	nodes from the live tree
+ */
+static void selftest_data_remove(void)
+{
+	struct device_node *np;
+	struct property *prop;
+
+	while (last_node_index >= 0) {
+		if (nodes[last_node_index]) {
+			np = of_find_node_by_path(nodes[last_node_index]->full_name);
+			if (strcmp(np->full_name, "/aliases") != 0) {
+				detach_node_and_children(np->child);
+				of_detach_node(np);
+			} else {
+				for_each_property_of_node(np, prop) {
+					if (strcmp(prop->name, "testcase-alias") == 0)
+						of_remove_property(np, prop);
+				}
+			}
+		}
+		last_node_index--;
+	}
+}
+
 static int __init of_selftest(void)
 {
 	struct device_node *np;
+	int res;
+
+	/* adding data for selftest */
+	res = selftest_data_add();
+	if (res)
+		return res;
 
 	np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
 	if (!np) {
···
 	of_selftest_dynamic();
 	of_selftest_parse_phandle_with_args();
 	of_selftest_property_match_string();
+	of_selftest_property_copy();
+	of_selftest_changeset();
 	of_selftest_parse_interrupts();
 	of_selftest_parse_interrupts_extended();
 	of_selftest_match_node();
 	of_selftest_platform_populate();
 	pr_info("end of selftest - %i passed, %i failed\n",
 		selftest_results.passed, selftest_results.failed);
+
+	/* removing selftest data from live tree */
+	selftest_data_remove();
+
 	return 0;
 }
 late_initcall(of_selftest);

drivers/of/testcase-data/testcases.dts

···
+/dts-v1/;
+/ {
+	testcase-data {
+		changeset {
+			prop-update = "hello";
+			prop-remove = "world";
+			node-remove {
+			};
+		};
+	};
+};
+#include "tests-phandle.dtsi"
+#include "tests-interrupts.dtsi"
+#include "tests-match.dtsi"
+#include "tests-platform.dtsi"

drivers/of/testcase-data/testcases.dtsi

···
-#include "tests-phandle.dtsi"
-#include "tests-interrupts.dtsi"
-#include "tests-match.dtsi"
-#include "tests-platform.dtsi"

drivers/pci/hotplug/rpaphp_core.c

···
 
 static int __init rpaphp_init(void)
 {
-	struct device_node *dn = NULL;
+	struct device_node *dn;
 
 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
 
-	while ((dn = of_find_node_by_name(dn, "pci")))
+	for_each_node_by_name(dn, "pci")
 		rpaphp_add_slot(dn);
 
 	return 0;

drivers/tty/ehv_bytechan.c

···
  *
  * The byte channel to be used for the console is specified via a "stdout"
  * property in the /chosen node.
- *
- * For compatible with legacy device trees, we also look for a "stdout" alias.
  */
 static int find_console_handle(void)
 {
-	struct device_node *np, *np2;
+	struct device_node *np = of_stdout;
 	const char *sprop = NULL;
 	const uint32_t *iprop;
 
-	np = of_find_node_by_path("/chosen");
-	if (np)
-		sprop = of_get_property(np, "stdout-path", NULL);
-
-	if (!np || !sprop) {
-		of_node_put(np);
-		np = of_find_node_by_name(NULL, "aliases");
-		if (np)
-			sprop = of_get_property(np, "stdout", NULL);
-	}
-
-	if (!sprop) {
-		of_node_put(np);
-		return 0;
-	}
-
 	/* We don't care what the aliased node is actually called.  We only
 	 * care if it's compatible with "epapr,hv-byte-channel", because that
-	 * indicates that it's a byte channel node.  We use a temporary
-	 * variable, 'np2', because we can't release 'np' until we're done with
-	 * 'sprop'.
+	 * indicates that it's a byte channel node.
 	 */
-	np2 = of_find_node_by_path(sprop);
-	of_node_put(np);
-	np = np2;
-	if (!np) {
-		pr_warning("ehv-bc: stdout node '%s' does not exist\n", sprop);
+	if (!np || !of_device_is_compatible(np, "epapr,hv-byte-channel"))
 		return 0;
-	}
-
-	/* Is it a byte channel? */
-	if (!of_device_is_compatible(np, "epapr,hv-byte-channel")) {
-		of_node_put(np);
-		return 0;
-	}
 
 	stdout_irq = irq_of_parse_and_map(np, 0);
 	if (stdout_irq == NO_IRQ) {
-		pr_err("ehv-bc: no 'interrupts' property in %s node\n", sprop);
-		of_node_put(np);
+		pr_err("ehv-bc: no 'interrupts' property in %s node\n", np->full_name);
 		return 0;
 	}
 
···
 	if (!iprop) {
 		pr_err("ehv-bc: no 'hv-handle' property in %s node\n",
 		       np->name);
-		of_node_put(np);
 		return 0;
 	}
 	stdout_bc = be32_to_cpu(*iprop);
-
-	of_node_put(np);
 	return 1;
 }
 

drivers/tty/hvc/hvc_opal.c

···
 
 void __init hvc_opal_init_early(void)
 {
-	struct device_node *stdout_node = NULL;
+	struct device_node *stdout_node = of_node_get(of_stdout);
 	const __be32 *termno;
-	const char *name = NULL;
 	const struct hv_ops *ops;
 	u32 index;
 
-	/* find the boot console from /chosen/stdout */
-	if (of_chosen)
-		name = of_get_property(of_chosen, "linux,stdout-path", NULL);
-	if (name) {
-		stdout_node = of_find_node_by_path(name);
-		if (!stdout_node) {
-			pr_err("hvc_opal: Failed to locate default console!\n");
-			return;
-		}
-	} else {
+	/* If the console wasn't in /chosen, try /ibm,opal */
+	if (!stdout_node) {
 		struct device_node *opal, *np;
 
 		/* Current OPAL takeover doesn't provide the stdout

drivers/tty/hvc/hvc_vio.c

···
 
 void __init hvc_vio_init_early(void)
 {
-	struct device_node *stdout_node;
 	const __be32 *termno;
 	const char *name;
 	const struct hv_ops *ops;
 
 	/* find the boot console from /chosen/stdout */
-	if (!of_chosen)
+	if (!of_stdout)
 		return;
-	name = of_get_property(of_chosen, "linux,stdout-path", NULL);
-	if (name == NULL)
-		return;
-	stdout_node = of_find_node_by_path(name);
-	if (!stdout_node)
-		return;
-	name = of_get_property(stdout_node, "name", NULL);
+	name = of_get_property(of_stdout, "name", NULL);
 	if (!name) {
 		printk(KERN_WARNING "stdout node missing 'name' property!\n");
-		goto out;
+		return;
 	}
 
 	/* Check if it's a virtual terminal */
 	if (strncmp(name, "vty", 3) != 0)
-		goto out;
-	termno = of_get_property(stdout_node, "reg", NULL);
+		return;
+	termno = of_get_property(of_stdout, "reg", NULL);
 	if (termno == NULL)
-		goto out;
+		return;
 	hvterm_priv0.termno = of_read_number(termno, 1);
 	spin_lock_init(&hvterm_priv0.buf_lock);
 	hvterm_privs[0] = &hvterm_priv0;
 
 	/* Check the protocol */
-	if (of_device_is_compatible(stdout_node, "hvterm1")) {
+	if (of_device_is_compatible(of_stdout, "hvterm1")) {
 		hvterm_priv0.proto = HV_PROTOCOL_RAW;
 		ops = &hvterm_raw_ops;
 	}
-	else if (of_device_is_compatible(stdout_node, "hvterm-protocol")) {
+	else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) {
 		hvterm_priv0.proto = HV_PROTOCOL_HVSI;
 		ops = &hvterm_hvsi_ops;
 		hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
···
 		/* HVSI, perform the handshake now */
 		hvsilib_establish(&hvterm_priv0.hvsi);
 	} else
-		goto out;
+		return;
 	udbg_putc = udbg_hvc_putc;
 	udbg_getc = udbg_hvc_getc;
 	udbg_getc_poll = udbg_hvc_getc_poll;
···
 	 * backend for HVSI, only do udbg
 	 */
 	if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
-		goto out;
+		return;
 #endif
 	/* Check whether the user has requested a different console. */
 	if (!strstr(cmd_line, "console="))
 		add_preferred_console("hvc", 0, NULL);
 	hvc_instantiate(0, 0, ops);
-out:
-	of_node_put(stdout_node);
 }
 
 /* call this from early_init() for a working debug console on

drivers/tty/serial/pmac_zilog.c

···
 	/*
 	 * Find all escc chips in the system
 	 */
-	node_p = of_find_node_by_name(NULL, "escc");
-	while (node_p) {
+	for_each_node_by_name(node_p, "escc") {
 		/*
 		 * First get channel A/B node pointers
 		 * 
···
 			of_node_put(node_b);
 			printk(KERN_ERR "pmac_zilog: missing node %c for escc %s\n",
 				(!node_a) ? 'a' : 'b', node_p->full_name);
-			goto next;
+			continue;
 		}
 
 		/*
···
 			of_node_put(node_b);
 			memset(&pmz_ports[count], 0, sizeof(struct uart_pmac_port));
 			memset(&pmz_ports[count+1], 0, sizeof(struct uart_pmac_port));
-			goto next;
+			continue;
 		}
 		count += 2;
-next:
-		node_p = of_find_node_by_name(node_p, "escc");
 	}
 	pmz_ports_count = count;
 

drivers/tty/serial/serial_core.c

···
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/console.h>
+#include <linux/of.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/device.h>
···
 		spin_lock_init(&uport->lock);
 		lockdep_set_class(&uport->lock, &port_lock_key);
 	}
+	if (uport->cons && uport->dev)
+		of_console_check(uport->dev->of_node, uport->cons->name, uport->line);
 
 	uart_configure_port(drv, state, uport);
 

include/linux/of.h

···
 	uint32_t args[MAX_PHANDLE_ARGS];
 };
 
-extern int of_node_add(struct device_node *node);
-
 /* initialize a node */
 extern struct kobj_type of_node_ktype;
 static inline void of_node_init(struct device_node *node)
···
 extern struct device_node *of_allnodes;
 extern struct device_node *of_chosen;
 extern struct device_node *of_aliases;
+extern struct device_node *of_stdout;
 extern raw_spinlock_t devtree_lock;
 
 static inline bool of_have_populated_dt(void)
···
 #define OF_DYNAMIC	1 /* node and properties were allocated via kmalloc */
 #define OF_DETACHED	2 /* node has been detached from the device tree */
 #define OF_POPULATED	3 /* device already created for the node */
+#define OF_POPULATED_BUS	4 /* of_platform_populate recursed to children of this node */
 
 #define OF_IS_DYNAMIC(x) test_bit(OF_DYNAMIC, &x->_flags)
 #define OF_MARK_DYNAMIC(x) set_bit(OF_DYNAMIC, &x->_flags)
···
 struct of_prop_reconfig {
 	struct device_node	*dn;
 	struct property		*prop;
+	struct property		*old_prop;
 };
 
 extern int of_reconfig_notifier_register(struct notifier_block *);
···
  */
 const char *of_prop_next_string(struct property *prop, const char *cur);
 
-int of_device_is_stdout_path(struct device_node *dn);
+bool of_console_check(struct device_node *dn, char *name, int index);
 
 #else /* CONFIG_OF */
 
···
 	return 0;
 }
 
-static inline int of_device_is_stdout_path(struct device_node *dn)
+static inline bool of_console_check(const struct device_node *dn, const char *name, int index)
 {
-	return 0;
+	return false;
 }
 
 static inline const __be32 *of_prop_next_u32(struct property *prop,
···
 		_OF_DECLARE(table, name, compat, fn, of_init_fn_1)
 #define OF_DECLARE_2(table, name, compat, fn) \
 		_OF_DECLARE(table, name, compat, fn, of_init_fn_2)
+
+/**
+ * struct of_changeset_entry	- Holds a changeset entry
+ *
+ * @node:	list_head for the log list
+ * @action:	notifier action
+ * @np:		pointer to the device node affected
+ * @prop:	pointer to the property affected
+ * @old_prop:	hold a pointer to the original property
+ *
+ * Every modification of the device tree during a changeset
+ * is held in a list of of_changeset_entry structures.
+ * That way we can recover from a partial application, or we can
+ * revert the changeset
+ */
+struct of_changeset_entry {
+	struct list_head node;
+	unsigned long action;
+	struct device_node *np;
+	struct property *prop;
+	struct property *old_prop;
+};
+
+/**
+ * struct of_changeset - changeset tracker structure
+ *
+ * @entries:	list_head for the changeset entries
+ *
+ * changesets are a convenient way to apply bulk changes to the
+ * live tree. In case of an error, changes are rolled-back.
+ * changesets live on after initial application, and if not
+ * destroyed after use, they can be reverted in one single call.
+ */
+struct of_changeset {
+	struct list_head entries;
+};
+
+#ifdef CONFIG_OF_DYNAMIC
+extern void of_changeset_init(struct of_changeset *ocs);
+extern void of_changeset_destroy(struct of_changeset *ocs);
+extern int of_changeset_apply(struct of_changeset *ocs);
+extern int of_changeset_revert(struct of_changeset *ocs);
+extern int of_changeset_action(struct of_changeset *ocs,
+		unsigned long action, struct device_node *np,
+		struct property *prop);
+
+static inline int of_changeset_attach_node(struct of_changeset *ocs,
+		struct device_node *np)
+{
+	return of_changeset_action(ocs, OF_RECONFIG_ATTACH_NODE, np, NULL);
+}
+
+static inline int of_changeset_detach_node(struct of_changeset *ocs,
+		struct device_node *np)
+{
+	return of_changeset_action(ocs, OF_RECONFIG_DETACH_NODE, np, NULL);
+}
+
+static inline int of_changeset_add_property(struct of_changeset *ocs,
+		struct device_node *np, struct property *prop)
+{
+	return of_changeset_action(ocs, OF_RECONFIG_ADD_PROPERTY, np, prop);
+}
+
+static inline int of_changeset_remove_property(struct of_changeset *ocs,
+		struct device_node *np, struct property *prop)
+{
+	return of_changeset_action(ocs, OF_RECONFIG_REMOVE_PROPERTY, np, prop);
+}
+
+static inline int of_changeset_update_property(struct of_changeset *ocs,
+		struct device_node *np, struct property *prop)
+{
+	return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
+}
+#endif
 
 #endif /* _LINUX_OF_H */

include/linux/of_platform.h

···
 				const struct of_device_id *matches,
 				const struct of_dev_auxdata *lookup,
 				struct device *parent);
-extern int of_platform_depopulate(struct device *parent);
+extern void of_platform_depopulate(struct device *parent);
 #else
 static inline int of_platform_populate(struct device_node *root,
 					const struct of_device_id *matches,
···
 {
 	return -ENODEV;
 }
-static inline int of_platform_depopulate(struct device *parent)
-{
-	return -ENODEV;
-}
+static inline void of_platform_depopulate(struct device *parent) { }
 #endif
 
 #endif	/* _LINUX_OF_PLATFORM_H */

include/linux/of_reserved_mem.h

···
 struct reserved_mem {
 	const char			*name;
 	unsigned long			fdt_node;
+	unsigned long			phandle;
 	const struct reserved_mem_ops	*ops;
 	phys_addr_t			base;
 	phys_addr_t			size;
···
 	_OF_DECLARE(reservedmem, name, compat, init, reservedmem_of_init_fn)
 
 #ifdef CONFIG_OF_RESERVED_MEM
+void of_reserved_mem_device_init(struct device *dev);
+void of_reserved_mem_device_release(struct device *dev);
+
 void fdt_init_reserved_mem(void);
 void fdt_reserved_mem_save_node(unsigned long node, const char *uname,
 			       phys_addr_t base, phys_addr_t size);
 #else
+static inline void of_reserved_mem_device_init(struct device *dev) { }
+static inline void of_reserved_mem_device_release(struct device *pdev) { }
+
 static inline void fdt_init_reserved_mem(void) { }
 static inline void fdt_reserved_mem_save_node(unsigned long node,
 		const char *uname, phys_addr_t base, phys_addr_t size) { }

sound/ppc/pmac.c

···
 		return -ENODEV;
 
 	if (!sound) {
-		sound = of_find_node_by_name(NULL, "sound");
-		while (sound && sound->parent != chip->node)
-			sound = of_find_node_by_name(sound, "sound");
+		for_each_node_by_name(sound, "sound")
+			if (sound->parent == chip->node)
+				break;
 	}
 	if (! sound) {
 		of_node_put(chip->node);