/* * Link physical devices with ACPI devices support * * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com> * Copyright (c) 2005 Intel Corp. * * This file is released under the GPLv2. */ #include <linux/init.h> #include <linux/list.h> #include <linux/device.h> #include <linux/rwsem.h> #include <linux/acpi.h> #define ACPI_GLUE_DEBUG 0 #if ACPI_GLUE_DEBUG #define DBG(x...) printk(PREFIX x) #else #define DBG(x...) #endif static LIST_HEAD(bus_type_list); static DECLARE_RWSEM(bus_type_sem); int register_acpi_bus_type(struct acpi_bus_type *type) { if (acpi_disabled) return -ENODEV; if (type && type->bus && type->find_device) { down_write(&bus_type_sem); list_add_tail(&type->list, &bus_type_list); up_write(&bus_type_sem); printk(KERN_INFO PREFIX "bus type %s registered\n", type->bus->name); return 0; } return -ENODEV; } EXPORT_SYMBOL(register_acpi_bus_type); int unregister_acpi_bus_type(struct acpi_bus_type *type) { if (acpi_disabled) return 0; if (type) { down_write(&bus_type_sem); list_del_init(&type->list); up_write(&bus_type_sem); printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n", type->bus->name); return 0; } return -ENODEV; } EXPORT_SYMBOL(unregister_acpi_bus_type); static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type) { struct acpi_bus_type *tmp, *ret = NULL; down_read(&bus_type_sem); list_for_each_entry(tmp, &bus_type_list, list) { if (tmp->bus == type) { ret = tmp; break; } } up_read(&bus_type_sem); return ret; } static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle) { struct acpi_bus_type *tmp; int ret = -ENODEV; down_read(&bus_type_sem); list_for_each_entry(tmp, &bus_type_list, list) { if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) { ret = 0; break; } } up_read(&bus_type_sem); return ret; } /* Get PCI root bridge's handle from its segment and bus number */ struct acpi_find_pci_root { unsigned int seg; unsigned int bus; acpi_handle handle; }; static acpi_status do_root_bridge_busnr_callback(struct acpi_resource *resource, void *data) { unsigned long *busnr = (unsigned long *)data; struct acpi_resource_address64 address; if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 && resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 && resource->type != ACPI_RESOURCE_TYPE_ADDRESS64) return AE_OK; acpi_resource_to_address64(resource, &address); if ((address.address_length > 0) && (address.resource_type == ACPI_BUS_NUMBER_RANGE)) *busnr = address.minimum; return AE_OK; } static int get_root_bridge_busnr(acpi_handle handle) { acpi_status status; unsigned long bus, bbn; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); status = acpi_evaluate_integer(handle, METHOD_NAME__BBN, NULL, &bbn); if (status == AE_NOT_FOUND) { /* Assume bus = 0 */ printk(KERN_INFO PREFIX "Assume root bridge [%s] bus is 0\n", (char *)buffer.pointer); status = AE_OK; bbn = 0; } if (ACPI_FAILURE(status)) { bbn = -ENODEV; goto exit; } if (bbn > 0) goto exit; /* _BBN in some systems return 0 for all root bridges */ bus = -1; status = acpi_walk_resources(handle, METHOD_NAME__CRS, do_root_bridge_busnr_callback, &bus); /* If _CRS failed, we just use _BBN */ if (ACPI_FAILURE(status) || (bus == -1)) goto exit; /* We select _CRS */ if (bbn != bus) { printk(KERN_INFO PREFIX "_BBN and _CRS returns different value for %s. Select _CRS\n", (char *)buffer.pointer); bbn = bus; } exit: acpi_os_free(buffer.pointer); return (int)bbn; } static acpi_status find_pci_rootbridge(acpi_handle handle, u32 lvl, void *context, void **rv) { struct acpi_find_pci_root *find = (struct acpi_find_pci_root *)context; unsigned long seg, bus; acpi_status status; int tmp; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL, &seg); if (status == AE_NOT_FOUND) { /* Assume seg = 0 */ status = AE_OK; seg = 0; } if (ACPI_FAILURE(status)) { status = AE_CTRL_DEPTH; goto exit; } tmp = get_root_bridge_busnr(handle); if (tmp < 0) { printk(KERN_ERR PREFIX "Find root bridge failed for %s\n", (char *)buffer.pointer); status = AE_CTRL_DEPTH; goto exit; } bus = tmp; if (seg == find->seg && bus == find->bus) find->handle = handle; status = AE_OK; exit: acpi_os_free(buffer.pointer); return status; } acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus) { struct acpi_find_pci_root find = { seg, bus, NULL }; acpi_get_devices(PCI_ROOT_HID_STRING, find_pci_rootbridge, &find, NULL); return find.handle; } EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle); /* Get device's handler per its address under its parent */ struct acpi_find_child { acpi_handle handle; acpi_integer address; }; static acpi_status do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv) { acpi_status status; struct acpi_device_info *info; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_find_child *find = (struct acpi_find_child *)context; status = acpi_get_object_info(handle, &buffer); if (ACPI_SUCCESS(status)) { info = buffer.pointer; if (info->address == find->address) find->handle = handle; acpi_os_free(buffer.pointer); } return AE_OK; } acpi_handle acpi_get_child(acpi_handle parent, acpi_integer address) { struct acpi_find_child find = { NULL, address }; if (!parent) return NULL; acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, do_acpi_find_child, &find, NULL); return find.handle; } EXPORT_SYMBOL(acpi_get_child); /* Link ACPI devices with physical devices */ static void acpi_glue_data_handler(acpi_handle handle, u32 function, void *context) { /* we provide an empty handler */ } /* Note: a success call will increase reference count by one */ struct device *acpi_get_physical_device(acpi_handle handle) { acpi_status status; struct device *dev; status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev); if (ACPI_SUCCESS(status)) return get_device(dev); return NULL; } EXPORT_SYMBOL(acpi_get_physical_device); static int acpi_bind_one(struct device *dev, acpi_handle handle) { acpi_status status; if (dev->firmware_data) { printk(KERN_WARNING PREFIX "Drivers changed 'firmware_data' for %s\n", dev->bus_id); return -EINVAL; } get_device(dev); status = acpi_attach_data(handle, acpi_glue_data_handler, dev); if (ACPI_FAILURE(status)) { put_device(dev); return -EINVAL; } dev->firmware_data = handle; return 0; } static int acpi_unbind_one(struct device *dev) { if (!dev->firmware_data) return 0; if (dev == acpi_get_physical_device(dev->firmware_data)) { /* acpi_get_physical_device increase refcnt by one */ put_device(dev); acpi_detach_data(dev->firmware_data, acpi_glue_data_handler); dev->firmware_data = NULL; /* acpi_bind_one increase refcnt by one */ put_device(dev); } else { printk(KERN_ERR PREFIX "Oops, 'firmware_data' corrupt for %s\n", dev->bus_id); } return 0; } static int acpi_platform_notify(struct device *dev) { struct acpi_bus_type *type; acpi_handle handle; int ret = -EINVAL; if (!dev->bus || !dev->parent) { /* bridge devices genernally haven't bus or parent */ ret = acpi_find_bridge_device(dev, &handle); goto end; } type = acpi_get_bus_type(dev->bus); if (!type) { DBG("No ACPI bus support for %s\n", dev->bus_id); ret = -EINVAL; goto end; } if ((ret = type->find_device(dev, &handle)) != 0) DBG("Can't get handler for %s\n", dev->bus_id); end: if (!ret) acpi_bind_one(dev, handle); #if ACPI_GLUE_DEBUG if (!ret) { struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; acpi_get_name(dev->firmware_data, ACPI_FULL_PATHNAME, &buffer); DBG("Device %s -> %s\n", dev->bus_id, (char *)buffer.pointer); acpi_os_free(buffer.pointer); } else DBG("Device %s -> No ACPI support\n", dev->bus_id); #endif return ret; } static int acpi_platform_notify_remove(struct device *dev) { acpi_unbind_one(dev); return 0; } static int __init init_acpi_device_notify(void) { if (acpi_disabled) return 0; if (platform_notify || platform_notify_remove) { printk(KERN_ERR PREFIX "Can't use platform_notify\n"); return 0; } platform_notify = acpi_platform_notify; platform_notify_remove = acpi_platform_notify_remove; return 0; } arch_initcall(init_acpi_device_notify);