Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 793 insertions, 0 deletions

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
new file mode 100644
index 000000000..8b1e76407
--- /dev/null
+++ b/drivers/of/platform.c
@@ -0,0 +1,793 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
+ *			 <benh@kernel.crashing.org>
+ *    and		 Arnd Bergmann, IBM Corp.
+ *    Merged from powerpc/kernel/of_platform.c and
+ *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
+ */
+
+#define pr_fmt(fmt)	"OF: " fmt
+
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/amba/bus.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/sysfb.h>
+
+#include "of_private.h"
+
+/**
+ * of_find_device_by_node - Find the platform_device associated with a node
+ * @np: Pointer to device tree node
+ *
+ * Takes a reference to the embedded struct device which needs to be dropped
+ * after use.
+ *
+ * Return: platform_device pointer, or NULL if not found
+ */
+struct platform_device *of_find_device_by_node(struct device_node *np)
+{
+	struct device *dev;
+
+	dev = bus_find_device_by_of_node(&platform_bus_type, np);
+	return dev ? to_platform_device(dev) : NULL;
+}
+EXPORT_SYMBOL(of_find_device_by_node);
+
+int of_device_add(struct platform_device *ofdev)
+{
+	BUG_ON(ofdev->dev.of_node == NULL);
+
+	/* name and id have to be set so that the platform bus doesn't get
+	 * confused on matching */
+	ofdev->name = dev_name(&ofdev->dev);
+	ofdev->id = PLATFORM_DEVID_NONE;
+
+	/*
+	 * If this device has not binding numa node in devicetree, that is
+	 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this
+	 * device is on the same node as the parent.
+	 */
+	set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
+
+	return device_add(&ofdev->dev);
+}
+
+int of_device_register(struct platform_device *pdev)
+{
+	device_initialize(&pdev->dev);
+	return of_device_add(pdev);
+}
+EXPORT_SYMBOL(of_device_register);
+
+void of_device_unregister(struct platform_device *ofdev)
+{
+	device_unregister(&ofdev->dev);
+}
+EXPORT_SYMBOL(of_device_unregister);
+
+#ifdef CONFIG_OF_ADDRESS
+static const struct of_device_id of_skipped_node_table[] = {
+	{ .compatible = "operating-points-v2", },
+	{} /* Empty terminated list */
+};
+
+/*
+ * The following routines scan a subtree and registers a device for
+ * each applicable node.
+ *
+ * Note: sparc doesn't use these routines because it has a different
+ * mechanism for creating devices from device tree nodes.
+ */
+
+/**
+ * of_device_alloc - Allocate and initialize an of_device
+ * @np: device node to assign to device
+ * @bus_id: Name to assign to the device.  May be null to use default name.
+ * @parent: Parent device.
+ */
+struct platform_device *of_device_alloc(struct device_node *np,
+				  const char *bus_id,
+				  struct device *parent)
+{
+	struct platform_device *dev;
+	int rc, i, num_reg = 0;
+	struct resource *res;
+
+	dev = platform_device_alloc("", PLATFORM_DEVID_NONE);
+	if (!dev)
+		return NULL;
+
+	/* count the io resources */
+	num_reg = of_address_count(np);
+
+	/* Populate the resource table */
+	if (num_reg) {
+		res = kzalloc_objs(*res, num_reg);
+		if (!res) {
+			platform_device_put(dev);
+			return NULL;
+		}
+
+		dev->num_resources = num_reg;
+		dev->resource = res;
+		for (i = 0; i < num_reg; i++, res++) {
+			rc = of_address_to_resource(np, i, res);
+			WARN_ON(rc);
+		}
+	}
+
+	/* setup generic device info */
+	platform_device_set_of_node(dev, np);
+	dev->dev.parent = parent ? : &platform_bus;
+
+	if (bus_id)
+		dev_set_name(&dev->dev, "%s", bus_id);
+	else
+		of_device_make_bus_id(&dev->dev);
+
+	return dev;
+}
+EXPORT_SYMBOL(of_device_alloc);
+
+/**
+ * of_platform_device_create_pdata - Alloc, initialize and register an of_device
+ * @np: pointer to node to create device for
+ * @bus_id: name to assign device
+ * @platform_data: pointer to populate platform_data pointer with
+ * @parent: Linux device model parent device.
+ *
+ * Return: Pointer to created platform device, or NULL if a device was not
+ * registered.  Unavailable devices will not get registered.
+ */
+static struct platform_device *of_platform_device_create_pdata(
+					struct device_node *np,
+					const char *bus_id,
+					void *platform_data,
+					struct device *parent)
+{
+	struct platform_device *dev;
+
+	pr_debug("create platform device: %pOF\n", np);
+
+	if (!of_device_is_available(np) ||
+	    of_node_test_and_set_flag(np, OF_POPULATED))
+		return NULL;
+
+	dev = of_device_alloc(np, bus_id, parent);
+	if (!dev)
+		goto err_clear_flag;
+
+	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+	if (!dev->dev.dma_mask)
+		dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
+	dev->dev.bus = &platform_bus_type;
+	dev->dev.platform_data = platform_data;
+	of_msi_configure(&dev->dev, dev->dev.of_node);
+
+	if (of_device_add(dev) != 0) {
+		platform_device_put(dev);
+		goto err_clear_flag;
+	}
+
+	return dev;
+
+err_clear_flag:
+	of_node_clear_flag(np, OF_POPULATED);
+	return NULL;
+}
+
+/**
+ * of_platform_device_create - Alloc, initialize and register an of_device
+ * @np: pointer to node to create device for
+ * @bus_id: name to assign device
+ * @parent: Linux device model parent device.
+ *
+ * Return: Pointer to created platform device, or NULL if a device was not
+ * registered.  Unavailable devices will not get registered.
+ */
+struct platform_device *of_platform_device_create(struct device_node *np,
+					    const char *bus_id,
+					    struct device *parent)
+{
+	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
+}
+EXPORT_SYMBOL(of_platform_device_create);
+
+#ifdef CONFIG_ARM_AMBA
+static struct amba_device *of_amba_device_create(struct device_node *node,
+						 const char *bus_id,
+						 void *platform_data,
+						 struct device *parent)
+{
+	struct amba_device *dev;
+	int ret;
+
+	pr_debug("Creating amba device %pOF\n", node);
+
+	if (!of_device_is_available(node) ||
+	    of_node_test_and_set_flag(node, OF_POPULATED))
+		return NULL;
+
+	dev = amba_device_alloc(NULL, 0, 0);
+	if (!dev)
+		goto err_clear_flag;
+
+	/* AMBA devices only support a single DMA mask */
+	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+	dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
+
+	/* setup generic device info */
+	device_set_node(&dev->dev, of_fwnode_handle(node));
+	dev->dev.parent = parent ? : &platform_bus;
+	dev->dev.platform_data = platform_data;
+	if (bus_id)
+		dev_set_name(&dev->dev, "%s", bus_id);
+	else
+		of_device_make_bus_id(&dev->dev);
+
+	/* Allow the HW Peripheral ID to be overridden */
+	of_property_read_u32(node, "arm,primecell-periphid", &dev->periphid);
+
+	ret = of_address_to_resource(node, 0, &dev->res);
+	if (ret) {
+		pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
+		       ret, node);
+		goto err_free;
+	}
+
+	ret = amba_device_add(dev, &iomem_resource);
+	if (ret) {
+		pr_err("amba_device_add() failed (%d) for %pOF\n",
+		       ret, node);
+		goto err_free;
+	}
+
+	return dev;
+
+err_free:
+	amba_device_put(dev);
+err_clear_flag:
+	of_node_clear_flag(node, OF_POPULATED);
+	return NULL;
+}
+#else /* CONFIG_ARM_AMBA */
+static struct amba_device *of_amba_device_create(struct device_node *node,
+						 const char *bus_id,
+						 void *platform_data,
+						 struct device *parent)
+{
+	return NULL;
+}
+#endif /* CONFIG_ARM_AMBA */
+
+/*
+ * of_dev_lookup() - Given a device node, lookup the preferred Linux name
+ */
+static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
+				 struct device_node *np)
+{
+	const struct of_dev_auxdata *auxdata;
+	struct resource res;
+	int compatible = 0;
+
+	if (!lookup)
+		return NULL;
+
+	auxdata = lookup;
+	for (; auxdata->compatible; auxdata++) {
+		if (!of_device_is_compatible(np, auxdata->compatible))
+			continue;
+		compatible++;
+		if (!of_address_to_resource(np, 0, &res))
+			if (res.start != auxdata->phys_addr)
+				continue;
+		pr_debug("%pOF: devname=%s\n", np, auxdata->name);
+		return auxdata;
+	}
+
+	if (!compatible)
+		return NULL;
+
+	/* Try compatible match if no phys_addr and name are specified */
+	auxdata = lookup;
+	for (; auxdata->compatible; auxdata++) {
+		if (!of_device_is_compatible(np, auxdata->compatible))
+			continue;
+		if (!auxdata->phys_addr && !auxdata->name) {
+			pr_debug("%pOF: compatible match\n", np);
+			return auxdata;
+		}
+	}
+
+	return NULL;
+}
+
+/**
+ * of_platform_bus_create() - Create a device for a node and its children.
+ * @bus: device node of the bus to instantiate
+ * @matches: match table for bus nodes
+ * @lookup: auxdata table for matching id and platform_data with device nodes
+ * @parent: parent for new device, or NULL for top level.
+ * @strict: require compatible property
+ *
+ * Creates a platform_device for the provided device_node, and optionally
+ * recursively create devices for all the child nodes.
+ */
+static int of_platform_bus_create(struct device_node *bus,
+				  const struct of_device_id *matches,
+				  const struct of_dev_auxdata *lookup,
+				  struct device *parent, bool strict)
+{
+	const struct of_dev_auxdata *auxdata;
+	struct platform_device *dev;
+	const char *bus_id = NULL;
+	void *platform_data = NULL;
+	int rc = 0;
+
+	/* Make sure it has a compatible property */
+	if (strict && (!of_property_present(bus, "compatible"))) {
+		pr_debug("%s() - skipping %pOF, no compatible prop\n",
+			 __func__, bus);
+		return 0;
+	}
+
+	/* Skip nodes for which we don't want to create devices */
+	if (unlikely(of_match_node(of_skipped_node_table, bus))) {
+		pr_debug("%s() - skipping %pOF node\n", __func__, bus);
+		return 0;
+	}
+
+	if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
+		pr_debug("%s() - skipping %pOF, already populated\n",
+			__func__, bus);
+		return 0;
+	}
+
+	auxdata = of_dev_lookup(lookup, bus);
+	if (auxdata) {
+		bus_id = auxdata->name;
+		platform_data = auxdata->platform_data;
+	}
+
+	if (of_device_is_compatible(bus, "arm,primecell")) {
+		/*
+		 * Don't return an error here to keep compatibility with older
+		 * device tree files.
+		 */
+		of_amba_device_create(bus, bus_id, platform_data, parent);
+		return 0;
+	}
+
+	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
+	if (!dev || !of_match_node(matches, bus))
+		return 0;
+
+	for_each_child_of_node_scoped(bus, child) {
+		pr_debug("   create child: %pOF\n", child);
+		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
+		if (rc)
+			break;
+	}
+	of_node_set_flag(bus, OF_POPULATED_BUS);
+	return rc;
+}
+
+/**
+ * of_platform_bus_probe() - Probe the device-tree for platform buses
+ * @root: parent of the first level to probe or NULL for the root of the tree
+ * @matches: match table for bus nodes
+ * @parent: parent to hook devices from, NULL for toplevel
+ *
+ * Note that children of the provided root are not instantiated as devices
+ * unless the specified root itself matches the bus list and is not NULL.
+ */
+int of_platform_bus_probe(struct device_node *root,
+			  const struct of_device_id *matches,
+			  struct device *parent)
+{
+	int rc = 0;
+
+	root = root ? of_node_get(root) : of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	pr_debug("%s()\n", __func__);
+	pr_debug(" starting at: %pOF\n", root);
+
+	/* Do a self check of bus type, if there's a match, create children */
+	if (of_match_node(matches, root)) {
+		rc = of_platform_bus_create(root, matches, NULL, parent, false);
+	} else {
+		for_each_child_of_node_scoped(root, child) {
+			if (!of_match_node(matches, child))
+				continue;
+			rc = of_platform_bus_create(child, matches, NULL, parent, false);
+			if (rc)
+				break;
+		}
+	}
+
+	of_node_put(root);
+	return rc;
+}
+EXPORT_SYMBOL(of_platform_bus_probe);
+
+/**
+ * of_platform_populate() - Populate platform_devices from device tree data
+ * @root: parent of the first level to probe or NULL for the root of the tree
+ * @matches: match table, NULL to use the default
+ * @lookup: auxdata table for matching id and platform_data with device nodes
+ * @parent: parent to hook devices from, NULL for toplevel
+ *
+ * Similar to of_platform_bus_probe(), this function walks the device tree
+ * and creates devices from nodes.  It differs in that it follows the modern
+ * convention of requiring all device nodes to have a 'compatible' property,
+ * and it is suitable for creating devices which are children of the root
+ * node (of_platform_bus_probe will only create children of the root which
+ * are selected by the @matches argument).
+ *
+ * New board support should be using this function instead of
+ * of_platform_bus_probe().
+ *
+ * Return: 0 on success, < 0 on failure.
+ */
+int of_platform_populate(struct device_node *root,
+			const struct of_device_id *matches,
+			const struct of_dev_auxdata *lookup,
+			struct device *parent)
+{
+	int rc = 0;
+
+	root = root ? of_node_get(root) : of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	pr_debug("%s()\n", __func__);
+	pr_debug(" starting at: %pOF\n", root);
+
+	device_links_supplier_sync_state_pause();
+	for_each_child_of_node_scoped(root, child) {
+		rc = of_platform_bus_create(child, matches, lookup, parent, true);
+		if (rc)
+			break;
+	}
+	device_links_supplier_sync_state_resume();
+
+	of_node_set_flag(root, OF_POPULATED_BUS);
+
+	of_node_put(root);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(of_platform_populate);
+
+int of_platform_default_populate(struct device_node *root,
+				 const struct of_dev_auxdata *lookup,
+				 struct device *parent)
+{
+	static const struct of_device_id match_table[] = {
+		{ .compatible = "simple-bus", },
+		{ .compatible = "simple-mfd", },
+		{ .compatible = "isa", },
+#ifdef CONFIG_ARM_AMBA
+		{ .compatible = "arm,amba-bus", },
+#endif /* CONFIG_ARM_AMBA */
+		{} /* Empty terminated list */
+	};
+
+	return of_platform_populate(root, match_table, lookup, parent);
+}
+EXPORT_SYMBOL_GPL(of_platform_default_populate);
+
+static const struct of_device_id reserved_mem_matches[] = {
+	{ .compatible = "phram" },
+	{ .compatible = "qcom,rmtfs-mem" },
+	{ .compatible = "qcom,cmd-db" },
+	{ .compatible = "qcom,smem" },
+	{ .compatible = "ramoops" },
+	{ .compatible = "nvmem-rmem" },
+	{ .compatible = "google,open-dice" },
+	{}
+};
+
+static int __init of_platform_default_populate_init(void)
+{
+	struct device_node *node, *reserved;
+
+	device_links_supplier_sync_state_pause();
+
+	if (IS_ENABLED(CONFIG_PPC)) {
+		struct device_node *boot_display = NULL;
+		struct platform_device *dev;
+		int display_number = 0;
+		int ret;
+
+		/* Check if we have a MacOS display without a node spec */
+		if (of_property_present(of_chosen, "linux,bootx-noscreen")) {
+			/*
+			 * The old code tried to work out which node was the MacOS
+			 * display based on the address. I'm dropping that since the
+			 * lack of a node spec only happens with old BootX versions
+			 * (users can update) and with this code, they'll still get
+			 * a display (just not the palette hacks).
+			 */
+			dev = platform_device_alloc("bootx-noscreen", 0);
+			if (WARN_ON(!dev))
+				return -ENOMEM;
+			ret = platform_device_add(dev);
+			if (WARN_ON(ret)) {
+				platform_device_put(dev);
+				return ret;
+			}
+		}
+
+		/*
+		 * For OF framebuffers, first create the device for the boot display,
+		 * then for the other framebuffers. Only fail for the boot display;
+		 * ignore errors for the rest.
+		 */
+		for_each_node_by_type(node, "display") {
+			if (!of_property_read_bool(node, "linux,opened") ||
+			    !of_property_read_bool(node, "linux,boot-display"))
+				continue;
+			dev = of_platform_device_create(node, "of-display", NULL);
+			of_node_put(node);
+			if (WARN_ON(!dev))
+				return -ENOMEM;
+			boot_display = node;
+			display_number++;
+			break;
+		}
+		for_each_node_by_type(node, "display") {
+			char buf[14];
+			const char *of_display_format = "of-display.%d";
+
+			if (!of_property_read_bool(node, "linux,opened") || node == boot_display)
+				continue;
+			ret = snprintf(buf, sizeof(buf), of_display_format, display_number++);
+			if (ret < sizeof(buf))
+				of_platform_device_create(node, buf, NULL);
+		}
+
+	} else {
+		/*
+		 * Handle certain compatibles explicitly, since we don't want to create
+		 * platform_devices for every node in /reserved-memory with a
+		 * "compatible",
+		 */
+		reserved = of_find_node_by_path("/reserved-memory");
+		if (reserved) {
+			for_each_child_of_node(reserved, node) {
+				if (of_match_node(reserved_mem_matches, node))
+					of_platform_device_create(node, NULL, NULL);
+			}
+			of_node_put(reserved);
+		}
+
+		node = of_find_node_by_path("/firmware");
+		if (node) {
+			of_platform_default_populate(node, NULL, NULL);
+			of_node_put(node);
+		}
+
+		node = of_get_compatible_child(of_chosen, "simple-framebuffer");
+		if (node) {
+			/*
+			 * Since a "simple-framebuffer" device is already added
+			 * here, disable the Generic System Framebuffers (sysfb)
+			 * to prevent it from registering another device for the
+			 * system framebuffer later (e.g: using the screen_info
+			 * data that may had been filled as well).
+			 *
+			 * This can happen for example on DT systems that do EFI
+			 * booting and may provide a GOP handle to the EFI stub.
+			 */
+			sysfb_disable(NULL);
+			of_platform_device_create(node, NULL, NULL);
+			of_node_put(node);
+		}
+
+		/* Populate everything else. */
+		of_platform_default_populate(NULL, NULL, NULL);
+	}
+
+	return 0;
+}
+arch_initcall_sync(of_platform_default_populate_init);
+
+static int __init of_platform_sync_state_init(void)
+{
+	device_links_supplier_sync_state_resume();
+	return 0;
+}
+late_initcall_sync(of_platform_sync_state_init);
+
+int of_platform_device_destroy(struct device *dev, void *data)
+{
+	/* Do not touch devices not populated from the device tree */
+	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
+		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);
+
+	of_node_clear_flag(dev->of_node, OF_POPULATED);
+	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
+
+	if (dev->bus == &platform_bus_type)
+		platform_device_unregister(to_platform_device(dev));
+#ifdef CONFIG_ARM_AMBA
+	else if (dev->bus == &amba_bustype)
+		amba_device_unregister(to_amba_device(dev));
+#endif
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_platform_device_destroy);
+
+/**
+ * of_platform_depopulate() - Remove devices populated from device tree
+ * @parent: device which children will be removed
+ *
+ * Complementary to of_platform_populate(), this function removes children
+ * of the given device (and, recursively, their children) that have been
+ * created from their respective device tree nodes (and only those,
+ * leaving others - eg. manually created - unharmed).
+ */
+void of_platform_depopulate(struct device *parent)
+{
+	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
+		device_for_each_child_reverse(parent, NULL, of_platform_device_destroy);
+		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
+	}
+}
+EXPORT_SYMBOL_GPL(of_platform_depopulate);
+
+static void devm_of_platform_populate_release(struct device *dev, void *res)
+{
+	of_platform_depopulate(*(struct device **)res);
+}
+
+/**
+ * devm_of_platform_populate() - Populate platform_devices from device tree data
+ * @dev: device that requested to populate from device tree data
+ *
+ * Similar to of_platform_populate(), but will automatically call
+ * of_platform_depopulate() when the device is unbound from the bus.
+ *
+ * Return: 0 on success, < 0 on failure.
+ */
+int devm_of_platform_populate(struct device *dev)
+{
+	struct device **ptr;
+	int ret;
+
+	if (!dev)
+		return -EINVAL;
+
+	ptr = devres_alloc(devm_of_platform_populate_release,
+			   sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
+	if (ret) {
+		devres_free(ptr);
+	} else {
+		*ptr = dev;
+		devres_add(dev, ptr);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devm_of_platform_populate);
+
+static int devm_of_platform_match(struct device *dev, void *res, void *data)
+{
+	struct device **ptr = res;
+
+	if (!ptr) {
+		WARN_ON(!ptr);
+		return 0;
+	}
+
+	return *ptr == data;
+}
+
+/**
+ * devm_of_platform_depopulate() - Remove devices populated from device tree
+ * @dev: device that requested to depopulate from device tree data
+ *
+ * Complementary to devm_of_platform_populate(), this function removes children
+ * of the given device (and, recursively, their children) that have been
+ * created from their respective device tree nodes (and only those,
+ * leaving others - eg. manually created - unharmed).
+ */
+void devm_of_platform_depopulate(struct device *dev)
+{
+	int ret;
+
+	ret = devres_release(dev, devm_of_platform_populate_release,
+			     devm_of_platform_match, dev);
+
+	WARN_ON(ret);
+}
+EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
+
+#ifdef CONFIG_OF_DYNAMIC
+static int of_platform_notify(struct notifier_block *nb,
+				unsigned long action, void *arg)
+{
+	struct of_reconfig_data *rd = arg;
+	struct platform_device *pdev_parent, *pdev;
+	bool children_left;
+	struct device_node *parent;
+
+	switch (of_reconfig_get_state_change(action, rd)) {
+	case OF_RECONFIG_CHANGE_ADD:
+		parent = rd->dn->parent;
+		/* verify that the parent is a bus (or the root node) */
+		if (!of_node_is_root(parent) &&
+		    !of_node_check_flag(parent, OF_POPULATED_BUS))
+			return NOTIFY_OK;	/* not for us */
+
+		/* already populated? (driver using of_populate manually) */
+		if (of_node_check_flag(rd->dn, OF_POPULATED))
+			return NOTIFY_OK;
+
+		/* pdev_parent may be NULL when no bus platform device */
+		pdev_parent = of_find_device_by_node(parent);
+		pdev = of_platform_device_create(rd->dn, NULL,
+				pdev_parent ? &pdev_parent->dev : NULL);
+		platform_device_put(pdev_parent);
+
+		if (pdev == NULL) {
+			pr_err("%s: failed to create for '%pOF'\n",
+					__func__, rd->dn);
+			/* of_platform_device_create tosses the error code */
+			return notifier_from_errno(-EINVAL);
+		}
+		break;
+
+	case OF_RECONFIG_CHANGE_REMOVE:
+
+		/* already depopulated? */
+		if (!of_node_check_flag(rd->dn, OF_POPULATED))
+			return NOTIFY_OK;
+
+		/* find our device by node */
+		pdev = of_find_device_by_node(rd->dn);
+		if (pdev == NULL)
+			return NOTIFY_OK;	/* no? not meant for us */
+
+		/* unregister takes one ref away */
+		of_platform_device_destroy(&pdev->dev, &children_left);
+
+		/* and put the reference of the find */
+		platform_device_put(pdev);
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block platform_of_notifier = {
+	.notifier_call = of_platform_notify,
+};
+
+void of_platform_register_reconfig_notifier(void)
+{
+	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
+#endif /* CONFIG_OF_ADDRESS */