/* * 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", }, { .compatible = "simple-mfd", }, #ifdef CONFIG_ARM_AMBA { .compatible = "arm,amba-bus", }, #endif /* CONFIG_ARM_AMBA */ {} /* Empty terminated list */ }; EXPORT_SYMBOL(of_default_bus_match_table); 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); of_msi_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) { of_node_put(child); 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) { of_node_put(child); break; } } 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) { return of_platform_populate(root, of_default_bus_match_table, lookup, parent); } EXPORT_SYMBOL_GPL(of_platform_default_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 */