/* * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp. * * 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 #include #include #include #include #include #include #include #include #include #include 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); static int platform_driver_probe_shim(struct platform_device *pdev) { struct platform_driver *pdrv; struct of_platform_driver *ofpdrv; const struct of_device_id *match; pdrv = container_of(pdev->dev.driver, struct platform_driver, driver); ofpdrv = container_of(pdrv, struct of_platform_driver, platform_driver); /* There is an unlikely chance that an of_platform driver might match * on a non-OF platform device. If so, then of_match_device() will * come up empty. Return -EINVAL in this case so other drivers get * the chance to bind. */ match = of_match_device(pdev->dev.driver->of_match_table, &pdev->dev); return match ? ofpdrv->probe(pdev, match) : -EINVAL; } static void platform_driver_shutdown_shim(struct platform_device *pdev) { struct platform_driver *pdrv; struct of_platform_driver *ofpdrv; pdrv = container_of(pdev->dev.driver, struct platform_driver, driver); ofpdrv = container_of(pdrv, struct of_platform_driver, platform_driver); ofpdrv->shutdown(pdev); } /** * of_register_platform_driver */ int of_register_platform_driver(struct of_platform_driver *drv) { char *of_name; /* setup of_platform_driver to platform_driver adaptors */ drv->platform_driver.driver = drv->driver; /* Prefix the driver name with 'of:' to avoid namespace collisions * and bogus matches. There are some drivers in the tree that * register both an of_platform_driver and a platform_driver with * the same name. This is a temporary measure until they are all * cleaned up --gcl July 29, 2010 */ of_name = kmalloc(strlen(drv->driver.name) + 5, GFP_KERNEL); if (!of_name) return -ENOMEM; sprintf(of_name, "of:%s", drv->driver.name); drv->platform_driver.driver.name = of_name; if (drv->probe) drv->platform_driver.probe = platform_driver_probe_shim; drv->platform_driver.remove = drv->remove; if (drv->shutdown) drv->platform_driver.shutdown = platform_driver_shutdown_shim; drv->platform_driver.suspend = drv->suspend; drv->platform_driver.resume = drv->resume; return platform_driver_register(&drv->platform_driver); } EXPORT_SYMBOL(of_register_platform_driver); void of_unregister_platform_driver(struct of_platform_driver *drv) { platform_driver_unregister(&drv->platform_driver); kfree(drv->platform_driver.driver.name); drv->platform_driver.driver.name = NULL; } EXPORT_SYMBOL(of_unregister_platform_driver); #if defined(CONFIG_PPC_DCR) #include #endif extern struct device_attribute of_platform_device_attrs[]; static int of_platform_bus_match(struct device *dev, struct device_driver *drv) { const struct of_device_id *matches = drv->of_match_table; if (!matches) return 0; return of_match_device(matches, dev) != NULL; } static int of_platform_device_probe(struct device *dev) { int error = -ENODEV; struct of_platform_driver *drv; struct platform_device *of_dev; const struct of_device_id *match; drv = to_of_platform_driver(dev->driver); of_dev = to_platform_device(dev); if (!drv->probe) return error; of_dev_get(of_dev); match = of_match_device(drv->driver.of_match_table, dev); if (match) error = drv->probe(of_dev, match); if (error) of_dev_put(of_dev); return error; } static int of_platform_device_remove(struct device *dev) { struct platform_device *of_dev = to_platform_device(dev); struct of_platform_driver *drv = to_of_platform_driver(dev->driver); if (dev->driver && drv->remove) drv->remove(of_dev); return 0; } static void of_platform_device_shutdown(struct device *dev) { struct platform_device *of_dev = to_platform_device(dev); struct of_platform_driver *drv = to_of_platform_driver(dev->driver); if (dev->driver && drv->shutdown) drv->shutdown(of_dev); } #ifdef CONFIG_PM_SLEEP static int of_platform_legacy_suspend(struct device *dev, pm_message_t mesg) { struct platform_device *of_dev = to_platform_device(dev); struct of_platform_driver *drv = to_of_platform_driver(dev->driver); int ret = 0; if (dev->driver && drv->suspend) ret = drv->suspend(of_dev, mesg); return ret; } static int of_platform_legacy_resume(struct device *dev) { struct platform_device *of_dev = to_platform_device(dev); struct of_platform_driver *drv = to_of_platform_driver(dev->driver); int ret = 0; if (dev->driver && drv->resume) ret = drv->resume(of_dev); return ret; } static int of_platform_pm_prepare(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (drv && drv->pm && drv->pm->prepare) ret = drv->pm->prepare(dev); return ret; } static void of_platform_pm_complete(struct device *dev) { struct device_driver *drv = dev->driver; if (drv && drv->pm && drv->pm->complete) drv->pm->complete(dev); } #ifdef CONFIG_SUSPEND static int of_platform_pm_suspend(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->suspend) ret = drv->pm->suspend(dev); } else { ret = of_platform_legacy_suspend(dev, PMSG_SUSPEND); } return ret; } static int of_platform_pm_suspend_noirq(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->suspend_noirq) ret = drv->pm->suspend_noirq(dev); } return ret; } static int of_platform_pm_resume(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->resume) ret = drv->pm->resume(dev); } else { ret = of_platform_legacy_resume(dev); } return ret; } static int of_platform_pm_resume_noirq(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->resume_noirq) ret = drv->pm->resume_noirq(dev); } return ret; } #else /* !CONFIG_SUSPEND */ #define of_platform_pm_suspend NULL #define of_platform_pm_resume NULL #define of_platform_pm_suspend_noirq NULL #define of_platform_pm_resume_noirq NULL #endif /* !CONFIG_SUSPEND */ #ifdef CONFIG_HIBERNATION static int of_platform_pm_freeze(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->freeze) ret = drv->pm->freeze(dev); } else { ret = of_platform_legacy_suspend(dev, PMSG_FREEZE); } return ret; } static int of_platform_pm_freeze_noirq(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->freeze_noirq) ret = drv->pm->freeze_noirq(dev); } return ret; } static int of_platform_pm_thaw(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->thaw) ret = drv->pm->thaw(dev); } else { ret = of_platform_legacy_resume(dev); } return ret; } static int of_platform_pm_thaw_noirq(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->thaw_noirq) ret = drv->pm->thaw_noirq(dev); } return ret; } static int of_platform_pm_poweroff(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->poweroff) ret = drv->pm->poweroff(dev); } else { ret = of_platform_legacy_suspend(dev, PMSG_HIBERNATE); } return ret; } static int of_platform_pm_poweroff_noirq(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->poweroff_noirq) ret = drv->pm->poweroff_noirq(dev); } return ret; } static int of_platform_pm_restore(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->restore) ret = drv->pm->restore(dev); } else { ret = of_platform_legacy_resume(dev); } return ret; } static int of_platform_pm_restore_noirq(struct device *dev) { struct device_driver *drv = dev->driver; int ret = 0; if (!drv) return 0; if (drv->pm) { if (drv->pm->restore_noirq) ret = drv->pm->restore_noirq(dev); } return ret; } #else /* !CONFIG_HIBERNATION */ #define of_platform_pm_freeze NULL #define of_platform_pm_thaw NULL #define of_platform_pm_poweroff NULL #define of_platform_pm_restore NULL #define of_platform_pm_freeze_noirq NULL #define of_platform_pm_thaw_noirq NULL #define of_platform_pm_poweroff_noirq NULL #define of_platform_pm_restore_noirq NULL #endif /* !CONFIG_HIBERNATION */ static struct dev_pm_ops of_platform_dev_pm_ops = { .prepare = of_platform_pm_prepare, .complete = of_platform_pm_complete, .suspend = of_platform_pm_suspend, .resume = of_platform_pm_resume, .freeze = of_platform_pm_freeze, .thaw = of_platform_pm_thaw, .poweroff = of_platform_pm_poweroff, .restore = of_platform_pm_restore, .suspend_noirq = of_platform_pm_suspend_noirq, .resume_noirq = of_platform_pm_resume_noirq, .freeze_noirq = of_platform_pm_freeze_noirq, .thaw_noirq = of_platform_pm_thaw_noirq, .poweroff_noirq = of_platform_pm_poweroff_noirq, .restore_noirq = of_platform_pm_restore_noirq, }; #define OF_PLATFORM_PM_OPS_PTR (&of_platform_dev_pm_ops) #else /* !CONFIG_PM_SLEEP */ #define OF_PLATFORM_PM_OPS_PTR NULL #endif /* !CONFIG_PM_SLEEP */ int of_bus_type_init(struct bus_type *bus, const char *name) { bus->name = name; bus->match = of_platform_bus_match; bus->probe = of_platform_device_probe; bus->remove = of_platform_device_remove; bus->shutdown = of_platform_device_shutdown; bus->dev_attrs = of_platform_device_attrs; bus->pm = OF_PLATFORM_PM_OPS_PTR; return bus_register(bus); } int of_register_driver(struct of_platform_driver *drv, struct bus_type *bus) { /* * Temporary: of_platform_bus used to be distinct from the platform * bus. It isn't anymore, and so drivers on the platform bus need * to be registered in a special way. * * After all of_platform_bus_type drivers are converted to * platform_drivers, this exception can be removed. */ if (bus == &platform_bus_type) return of_register_platform_driver(drv); /* register with core */ drv->driver.bus = bus; return driver_register(&drv->driver); } EXPORT_SYMBOL(of_register_driver); void of_unregister_driver(struct of_platform_driver *drv) { if (drv->driver.bus == &platform_bus_type) of_unregister_platform_driver(drv); else driver_unregister(&drv->driver); } EXPORT_SYMBOL(of_unregister_driver); #if !defined(CONFIG_SPARC) /* * 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 either the dcr-reg or the reg property * value to derive a unique name. As a last resort it will use the node * name followed by a unique number. */ void of_device_make_bus_id(struct device *dev) { static atomic_t bus_no_reg_magic; struct device_node *node = dev->of_node; const u32 *reg; u64 addr; int magic; #ifdef CONFIG_PPC_DCR /* * If it's a DCR based device, use 'd' for native DCRs * and 'D' for MMIO DCRs. */ reg = of_get_property(node, "dcr-reg", NULL); if (reg) { #ifdef CONFIG_PPC_DCR_NATIVE dev_set_name(dev, "d%x.%s", *reg, node->name); #else /* CONFIG_PPC_DCR_NATIVE */ u64 addr = of_translate_dcr_address(node, *reg, NULL); if (addr != OF_BAD_ADDR) { dev_set_name(dev, "D%llx.%s", (unsigned long long)addr, node->name); return; } #endif /* !CONFIG_PPC_DCR_NATIVE */ } #endif /* CONFIG_PPC_DCR */ /* * For MMIO, get the physical address */ reg = of_get_property(node, "reg", NULL); if (reg) { addr = of_translate_address(node, reg); if (addr != OF_BAD_ADDR) { dev_set_name(dev, "%llx.%s", (unsigned long long)addr, node->name); return; } } /* * No BusID, use the node name and add a globally incremented * counter (and pray...) */ magic = atomic_add_return(1, &bus_no_reg_magic); dev_set_name(dev, "%s.%d", node->name, magic - 1); } /** * 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); } WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq); } dev->dev.of_node = of_node_get(np); #if defined(CONFIG_PPC) || defined(CONFIG_MICROBLAZE) dev->dev.dma_mask = &dev->archdata.dma_mask; #endif dev->dev.parent = parent; 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 - 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) { struct platform_device *dev; if (!of_device_is_available(np)) return NULL; dev = of_device_alloc(np, bus_id, parent); if (!dev) return NULL; #if defined(CONFIG_PPC) || defined(CONFIG_MICROBLAZE) dev->archdata.dma_mask = 0xffffffffUL; #endif dev->dev.coherent_dma_mask = DMA_BIT_MASK(32); dev->dev.bus = &platform_bus_type; /* We do not fill the DMA ops for platform devices by default. * This is currently the responsibility of the platform code * to do such, possibly using a device notifier */ if (of_device_add(dev) != 0) { platform_device_put(dev); return NULL; } return dev; } EXPORT_SYMBOL(of_platform_device_create); struct of_platform_prepare_data { struct list_head list; struct device_node *node; struct device *dev; /* assigned device */ int num_resources; struct resource resource[0]; }; static LIST_HEAD(of_platform_prepare_list); static struct notifier_block of_platform_nb; static struct of_platform_prepare_data *of_platform_find_prepare_data( struct device_node *node) { struct of_platform_prepare_data *prep; list_for_each_entry(prep, &of_platform_prepare_list, list) if (prep->node == node) return prep; return NULL; } static bool of_pdev_match_resources(struct platform_device *pdev, struct of_platform_prepare_data *prep) { struct resource *node_res = prep->resource; struct resource *pdev_res; int i, j; if (prep->num_resources == 0 || pdev->num_resources == 0) return false; dev_dbg(&pdev->dev, "compare dt node %s\n", prep->node->full_name); /* Compare both resource tables and make sure every node resource * is represented by the platform device. Here we check that each * resource has corresponding entry with the same type and start * values, and the end value falls inside the range specified * in the device tree node. */ for (i = 0; i < prep->num_resources; i++, node_res++) { pr_debug(" node res %2i:%.8x..%.8x[%lx]...\n", i, node_res->start, node_res->end, node_res->flags); pdev_res = pdev->resource; for (j = 0; j < pdev->num_resources; j++, pdev_res++) { pr_debug(" pdev res %2i:%.8x..%.8x[%lx]\n", j, pdev_res->start, pdev_res->end, pdev_res->flags); if ((pdev_res->start == node_res->start) && (pdev_res->end >= node_res->start) && (pdev_res->end <= node_res->end) && (pdev_res->flags == node_res->flags)) { pr_debug(" ...MATCH! :-)\n"); break; } } if (j >= pdev->num_resources) return false; } return true; } static int of_platform_device_notifier_call(struct notifier_block *nb, unsigned long event, void *_dev) { struct platform_device *pdev = to_platform_device(_dev); struct of_platform_prepare_data *prep; switch (event) { case BUS_NOTIFY_ADD_DEVICE: if (pdev->dev.of_node) return NOTIFY_DONE; list_for_each_entry(prep, &of_platform_prepare_list, list) { if (prep->dev) continue; if (!of_pdev_match_resources(pdev, prep)) continue; /* If disabled, don't let the device bind */ if (!of_device_is_available(prep->node)) { char buf[strlen(pdev->name) + 12]; dev_info(&pdev->dev, "disabled by dt node %s\n", prep->node->full_name); sprintf(buf, "%s-disabled", pdev->name); pdev->name = kstrdup(buf, GFP_KERNEL); continue; } dev_info(&pdev->dev, "attaching dt node %s\n", prep->node->full_name); prep->dev = get_device(&pdev->dev); pdev->dev.of_node = of_node_get(prep->node); return NOTIFY_OK; } break; case BUS_NOTIFY_DEL_DEVICE: list_for_each_entry(prep, &of_platform_prepare_list, list) { if (prep->dev == &pdev->dev) { dev_info(&pdev->dev, "detaching dt node %s\n", prep->node->full_name); of_node_put(pdev->dev.of_node); put_device(prep->dev); pdev->dev.of_node = NULL; prep->dev = NULL; return NOTIFY_OK; } } break; } return NOTIFY_DONE; } /** * of_platform_prepare - Flag nodes to be used for creating devices * @root: parent of the first level to probe or NULL for the root of the tree * @bus_match: match table for child bus nodes, or NULL * * This function sets up 'snooping' of device tree registrations and * when a device registration is found that matches a node in the * device tree, it populates the platform_device with a pointer to the * matching node. * * A bus notifier is used to implement this behaviour. When this * function is called, it will parse all the child nodes of @root and * create a lookup table of eligible device nodes. A device node is * considered eligible if it: * a) has a compatible property, * b) has memory mapped registers, and * c) has a mappable interrupt. * * It will also recursively parse child buses providing * a) the child bus node has a ranges property (children have * memory-mapped registers), and * b) it is compatible with the @matches list. * * The lookup table will be used as data for a platform bus notifier * that will compare each new device registration with the table * before a device driver is bound to it. If there is a match, then * the of_node pointer will be added to the device. Therefore it is * important to call this function *before* any platform devices get * registered. */ void of_platform_prepare(struct device_node *root, const struct of_device_id *matches) { struct device_node *child; struct of_platform_prepare_data *prep; /* register the notifier if it isn't already */ if (!of_platform_nb.notifier_call) { of_platform_nb.notifier_call = of_platform_device_notifier_call; bus_register_notifier(&platform_bus_type, &of_platform_nb); } /* If root is null, then start at the root of the tree */ root = root ? of_node_get(root) : of_find_node_by_path("/"); if (!root) return; pr_debug("of_platform_prepare()\n"); pr_debug(" starting at: %s\n", root->full_name); /* Loop over children and record the details */ for_each_child_of_node(root, child) { struct resource *res; int num_irq, num_reg, i; /* If this is a bus node, recursively inspect the children, * but *don't* prepare it. Prepare only concerns * itself with leaf-nodes. */ if (of_match_node(matches, child)) { of_platform_prepare(child, matches); continue; } /* Is it already in the list? */ if (of_platform_find_prepare_data(child)) continue; /* Make sure it has a compatible property */ if (!of_get_property(child, "compatible", NULL)) continue; /* * Count the resources. If the device doesn't have any * register ranges, then it gets skipped because there is no * way to match such a device against static registration */ num_irq = of_irq_count(child); num_reg = of_address_count(child); if (!num_reg) continue; /* Device node looks valid; record the details */ prep = kzalloc(sizeof(*prep) + (sizeof(prep->resource[0]) * (num_irq + num_reg)), GFP_KERNEL); if (!prep) return; /* We're screwed if malloc doesn't work. */ INIT_LIST_HEAD(&prep->list); res = &prep->resource[0]; for (i = 0; i < num_reg; i++, res++) WARN_ON(of_address_to_resource(child, i, res)); WARN_ON(of_irq_to_resource_table(child, res, num_irq) != num_irq); prep->num_resources = num_reg + num_irq; prep->node = of_node_get(child); list_add_tail(&prep->list, &of_platform_prepare_list); pr_debug("%s() - %s prepared (%i regs, %i irqs)\n", __func__, prep->node->full_name, num_reg, num_irq); } } /** * 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 * disallow recursive creation of child buses * @parent: parent for new device, or NULL for top level. * * 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, struct device *parent, bool strict) { struct of_platform_prepare_data *prep; struct device_node *child; struct platform_device *dev; 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; } /* Has the device already been registered manually? */ prep = of_platform_find_prepare_data(bus); if (prep && prep->dev) { pr_debug("%s() - skipping %s, already registered\n", __func__, bus->full_name); return 0; } dev = of_platform_device_create(bus, NULL, 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, &dev->dev, strict); if (rc) { of_node_put(child); break; } } 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, parent, false); } else for_each_child_of_node(root, child) { if (!of_match_node(matches, child)) continue; rc = of_platform_bus_create(child, matches, 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 * @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, 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, parent, true); if (rc) break; } of_node_put(root); return rc; } #endif /* !CONFIG_SPARC */