diff options
-rw-r--r-- | drivers/acpi/glue.c | 99 | ||||
-rw-r--r-- | drivers/pci/pci-acpi.c | 15 | ||||
-rw-r--r-- | include/acpi/acpi_bus.h | 6 |
3 files changed, 98 insertions, 22 deletions
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 17e15d11bd3..408f6b2a5fa 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -79,34 +79,99 @@ static struct acpi_bus_type *acpi_get_bus_type(struct device *dev) return ret; } -static acpi_status do_acpi_find_child(acpi_handle handle, u32 lvl_not_used, - void *addr_p, void **ret_p) +static acpi_status acpi_dev_present(acpi_handle handle, u32 lvl_not_used, + void *not_used, void **ret_p) { - unsigned long long addr, sta; - acpi_status status; + struct acpi_device *adev = NULL; - status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr); - if (ACPI_SUCCESS(status) && addr == *((u64 *)addr_p)) { + acpi_bus_get_device(handle, &adev); + if (adev) { *ret_p = handle; - status = acpi_bus_get_status_handle(handle, &sta); - if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_ENABLED)) - return AE_CTRL_TERMINATE; + return AE_CTRL_TERMINATE; } return AE_OK; } -acpi_handle acpi_get_child(acpi_handle parent, u64 address) +static bool acpi_extra_checks_passed(acpi_handle handle, bool is_bridge) { - void *ret = NULL; + unsigned long long sta; + acpi_status status; + + status = acpi_bus_get_status_handle(handle, &sta); + if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED)) + return false; + + if (is_bridge) { + void *test = NULL; + + /* Check if this object has at least one child device. */ + acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, + acpi_dev_present, NULL, NULL, &test); + return !!test; + } + return true; +} + +struct find_child_context { + u64 addr; + bool is_bridge; + acpi_handle ret; + bool ret_checked; +}; + +static acpi_status do_find_child(acpi_handle handle, u32 lvl_not_used, + void *data, void **not_used) +{ + struct find_child_context *context = data; + unsigned long long addr; + acpi_status status; - if (!parent) - return NULL; + status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr); + if (ACPI_FAILURE(status) || addr != context->addr) + return AE_OK; - acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, NULL, - do_acpi_find_child, &address, &ret); - return (acpi_handle)ret; + if (!context->ret) { + /* This is the first matching object. Save its handle. */ + context->ret = handle; + return AE_OK; + } + /* + * There is more than one matching object with the same _ADR value. + * That really is unexpected, so we are kind of beyond the scope of the + * spec here. We have to choose which one to return, though. + * + * First, check if the previously found object is good enough and return + * its handle if so. Second, check the same for the object that we've + * just found. + */ + if (!context->ret_checked) { + if (acpi_extra_checks_passed(context->ret, context->is_bridge)) + return AE_CTRL_TERMINATE; + else + context->ret_checked = true; + } + if (acpi_extra_checks_passed(handle, context->is_bridge)) { + context->ret = handle; + return AE_CTRL_TERMINATE; + } + return AE_OK; +} + +acpi_handle acpi_find_child(acpi_handle parent, u64 addr, bool is_bridge) +{ + if (parent) { + struct find_child_context context = { + .addr = addr, + .is_bridge = is_bridge, + }; + + acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, do_find_child, + NULL, &context, NULL); + return context.ret; + } + return NULL; } -EXPORT_SYMBOL(acpi_get_child); +EXPORT_SYMBOL_GPL(acpi_find_child); int acpi_bind_one(struct device *dev, acpi_handle handle) { diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index dbdc5f7e2b2..01e264fb50e 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -317,13 +317,20 @@ void acpi_pci_remove_bus(struct pci_bus *bus) /* ACPI bus type */ static int acpi_pci_find_device(struct device *dev, acpi_handle *handle) { - struct pci_dev * pci_dev; - u64 addr; + struct pci_dev *pci_dev = to_pci_dev(dev); + bool is_bridge; + u64 addr; - pci_dev = to_pci_dev(dev); + /* + * pci_is_bridge() is not suitable here, because pci_dev->subordinate + * is set only after acpi_pci_find_device() has been called for the + * given device. + */ + is_bridge = pci_dev->hdr_type == PCI_HEADER_TYPE_BRIDGE + || pci_dev->hdr_type == PCI_HEADER_TYPE_CARDBUS; /* Please ref to ACPI spec for the syntax of _ADR */ addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn); - *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr); + *handle = acpi_find_child(ACPI_HANDLE(dev->parent), addr, is_bridge); if (!*handle) return -ENODEV; return 0; diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 5026aaa3513..94383a70c1a 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -441,7 +441,11 @@ struct acpi_pci_root { }; /* helper */ -acpi_handle acpi_get_child(acpi_handle, u64); +acpi_handle acpi_find_child(acpi_handle, u64, bool); +static inline acpi_handle acpi_get_child(acpi_handle handle, u64 addr) +{ + return acpi_find_child(handle, addr, false); +} int acpi_is_root_bridge(acpi_handle); struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle); #define DEVICE_ACPI_HANDLE(dev) ((acpi_handle)ACPI_HANDLE(dev)) |