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-rw-r--r--kernel/drivers/of/platform.c566
1 files changed, 566 insertions, 0 deletions
diff --git a/kernel/drivers/of/platform.c b/kernel/drivers/of/platform.c
new file mode 100644
index 000000000..a01f57c9e
--- /dev/null
+++ b/kernel/drivers/of/platform.c
@@ -0,0 +1,566 @@
+/*
+ * 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
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+#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>
+
+const struct of_device_id of_default_bus_match_table[] = {
+ { .compatible = "simple-bus", },
+#ifdef CONFIG_ARM_AMBA
+ { .compatible = "arm,amba-bus", },
+#endif /* CONFIG_ARM_AMBA */
+ {} /* Empty terminated list */
+};
+
+static int of_dev_node_match(struct device *dev, void *data)
+{
+ return dev->of_node == data;
+}
+
+/**
+ * of_find_device_by_node - Find the platform_device associated with a node
+ * @np: Pointer to device tree node
+ *
+ * Returns 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(&platform_bus_type, NULL, np, of_dev_node_match);
+ return dev ? to_platform_device(dev) : NULL;
+}
+EXPORT_SYMBOL(of_find_device_by_node);
+
+#ifdef CONFIG_OF_ADDRESS
+/*
+ * 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_make_bus_id - Use the device node data to assign a unique name
+ * @dev: pointer to device structure that is linked to a device tree node
+ *
+ * This routine will first try using the translated bus address to
+ * derive a unique name. If it cannot, then it will prepend names from
+ * parent nodes until a unique name can be derived.
+ */
+void of_device_make_bus_id(struct device *dev)
+{
+ struct device_node *node = dev->of_node;
+ const __be32 *reg;
+ u64 addr;
+
+ /* Construct the name, using parent nodes if necessary to ensure uniqueness */
+ while (node->parent) {
+ /*
+ * If the address can be translated, then that is as much
+ * uniqueness as we need. Make it the first component and return
+ */
+ reg = of_get_property(node, "reg", NULL);
+ if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
+ dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
+ (unsigned long long)addr, node->name,
+ dev_name(dev));
+ return;
+ }
+
+ /* format arguments only used if dev_name() resolves to NULL */
+ dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
+ strrchr(node->full_name, '/') + 1, dev_name(dev));
+ node = node->parent;
+ }
+}
+
+/**
+ * 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, num_irq;
+ struct resource *res, temp_res;
+
+ dev = platform_device_alloc("", -1);
+ if (!dev)
+ return NULL;
+
+ /* count the io and irq resources */
+ while (of_address_to_resource(np, num_reg, &temp_res) == 0)
+ num_reg++;
+ num_irq = of_irq_count(np);
+
+ /* Populate the resource table */
+ if (num_irq || num_reg) {
+ res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
+ if (!res) {
+ platform_device_put(dev);
+ return NULL;
+ }
+
+ dev->num_resources = num_reg + num_irq;
+ dev->resource = res;
+ for (i = 0; i < num_reg; i++, res++) {
+ rc = of_address_to_resource(np, i, res);
+ WARN_ON(rc);
+ }
+ if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
+ pr_debug("not all legacy IRQ resources mapped for %s\n",
+ np->name);
+ }
+
+ dev->dev.of_node = of_node_get(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);
+
+static void of_dma_deconfigure(struct device *dev)
+{
+ arch_teardown_dma_ops(dev);
+}
+
+/**
+ * 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.
+ *
+ * Returns 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;
+
+ 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.bus = &platform_bus_type;
+ dev->dev.platform_data = platform_data;
+ of_dma_configure(&dev->dev, dev->dev.of_node);
+
+ if (of_device_add(dev) != 0) {
+ of_dma_deconfigure(&dev->dev);
+ 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.
+ *
+ * Returns 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;
+ const void *prop;
+ int i, ret;
+
+ pr_debug("Creating amba device %s\n", node->full_name);
+
+ 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) {
+ pr_err("%s(): amba_device_alloc() failed for %s\n",
+ __func__, node->full_name);
+ goto err_clear_flag;
+ }
+
+ /* setup generic device info */
+ dev->dev.of_node = of_node_get(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);
+ of_dma_configure(&dev->dev, dev->dev.of_node);
+
+ /* Allow the HW Peripheral ID to be overridden */
+ prop = of_get_property(node, "arm,primecell-periphid", NULL);
+ if (prop)
+ dev->periphid = of_read_ulong(prop, 1);
+
+ /* Decode the IRQs and address ranges */
+ for (i = 0; i < AMBA_NR_IRQS; i++)
+ dev->irq[i] = irq_of_parse_and_map(node, i);
+
+ ret = of_address_to_resource(node, 0, &dev->res);
+ if (ret) {
+ pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
+ __func__, ret, node->full_name);
+ goto err_free;
+ }
+
+ ret = amba_device_add(dev, &iomem_resource);
+ if (ret) {
+ pr_err("%s(): amba_device_add() failed (%d) for %s\n",
+ __func__, ret, node->full_name);
+ 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_devname_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)
+{
+ struct resource res;
+
+ if (!lookup)
+ return NULL;
+
+ for(; lookup->compatible != NULL; lookup++) {
+ if (!of_device_is_compatible(np, lookup->compatible))
+ continue;
+ if (!of_address_to_resource(np, 0, &res))
+ if (res.start != lookup->phys_addr)
+ continue;
+ pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
+ return lookup;
+ }
+
+ 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 device_node *child;
+ 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_get_property(bus, "compatible", NULL))) {
+ pr_debug("%s() - skipping %s, no compatible prop\n",
+ __func__, bus->full_name);
+ 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(bus, child) {
+ pr_debug(" create child: %s\n", child->full_name);
+ rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
+ if (rc) {
+ of_node_put(child);
+ 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)
+{
+ struct device_node *child;
+ int rc = 0;
+
+ root = root ? of_node_get(root) : of_find_node_by_path("/");
+ if (!root)
+ return -EINVAL;
+
+ pr_debug("of_platform_bus_probe()\n");
+ pr_debug(" starting at: %s\n", root->full_name);
+
+ /* 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(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().
+ *
+ * Returns 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)
+{
+ struct device_node *child;
+ int rc = 0;
+
+ root = root ? of_node_get(root) : of_find_node_by_path("/");
+ if (!root)
+ return -EINVAL;
+
+ for_each_child_of_node(root, child) {
+ rc = of_platform_bus_create(child, matches, lookup, parent, true);
+ if (rc)
+ break;
+ }
+ of_node_set_flag(root, OF_POPULATED_BUS);
+
+ of_node_put(root);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(of_platform_populate);
+
+static 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);
+
+ 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
+
+ of_dma_deconfigure(dev);
+ 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 children will be removed
+ *
+ * Complementary to of_platform_populate(), this function removes children
+ * of the given device (and, recurrently, their children) that have been
+ * created from their respective device tree nodes (and only those,
+ * leaving others - eg. manually created - unharmed).
+ *
+ * Returns 0 when all children devices have been removed or
+ * -EBUSY when some children remained.
+ */
+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(parent, NULL, of_platform_device_destroy);
+ of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
+ }
+}
+EXPORT_SYMBOL_GPL(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;
+
+ switch (of_reconfig_get_state_change(action, rd)) {
+ case OF_RECONFIG_CHANGE_ADD:
+ /* verify that the parent is a bus */
+ if (!of_node_check_flag(rd->dn->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(rd->dn->parent);
+ pdev = of_platform_device_create(rd->dn, NULL,
+ pdev_parent ? &pdev_parent->dev : NULL);
+ of_dev_put(pdev_parent);
+
+ if (pdev == NULL) {
+ pr_err("%s: failed to create for '%s'\n",
+ __func__, rd->dn->full_name);
+ /* 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 */
+ of_dev_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 */