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Diffstat (limited to '')
| -rw-r--r-- | drivers/of/platform.c | 726 |
1 files changed, 726 insertions, 0 deletions
diff --git a/drivers/of/platform.c b/drivers/of/platform.c new file mode 100644 index 000000000..04ad312fd --- /dev/null +++ b/drivers/of/platform.c @@ -0,0 +1,726 @@ +// 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_iommu.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", }, + { .compatible = "isa", }, +#ifdef CONFIG_ARM_AMBA + { .compatible = "arm,amba-bus", }, +#endif /* CONFIG_ARM_AMBA */ + {} /* Empty terminated list */ +}; + +static const struct of_device_id of_skipped_node_table[] = { + { .compatible = "operating-points-v2", }, + {} /* 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 + * + * Takes a reference to the embedded struct device which needs to be dropped + * after use. + * + * 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. + */ +static 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.%pOFn:%s" : "%llx.%pOFn", + (unsigned long long)addr, node, + dev_name(dev)); + return; + } + + /* format arguments only used if dev_name() resolves to NULL */ + dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s", + kbasename(node->full_name), 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("", PLATFORM_DEVID_NONE); + 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 = kcalloc(num_irq + num_reg, sizeof(*res), 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 %pOFn\n", + np); + } + + dev->dev.of_node = of_node_get(np); + dev->dev.fwnode = &np->fwnode; + 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. + * + * 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.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. + * + * 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 %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 */ + dev->dev.of_node = of_node_get(node); + dev->dev.fwnode = &node->fwnode; + 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 */ + 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("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_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) +{ + 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 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 %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(bus, child) { + pr_debug(" create child: %pOF\n", child); + 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("%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(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; + + pr_debug("%s()\n", __func__); + pr_debug(" starting at: %pOF\n", root); + + 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); + +#ifndef CONFIG_PPC +static const struct of_device_id reserved_mem_matches[] = { + { .compatible = "qcom,rmtfs-mem" }, + { .compatible = "qcom,cmd-db" }, + { .compatible = "ramoops" }, + {} +}; + +static int __init of_platform_default_populate_init(void) +{ + struct device_node *node; + + if (!of_have_populated_dt()) + return -ENODEV; + + /* + * Handle certain compatibles explicitly, since we don't want to create + * platform_devices for every node in /reserved-memory with a + * "compatible", + */ + for_each_matching_node(node, reserved_mem_matches) + of_platform_device_create(node, NULL, NULL); + + node = of_find_node_by_path("/firmware"); + if (node) { + of_platform_populate(node, NULL, 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); +#endif + +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, recurrently, 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(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. + * + * Returns 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, recurrently, 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; + + 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 '%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 */ + 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 */ |