diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 94672297e1b1..10f0f40587bb 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -79,6 +79,9 @@ static struct acpi_bus_type *acpi_get_bus_type(struct device *dev) return ret; } +#define FIND_CHILD_MIN_SCORE 1 +#define FIND_CHILD_MAX_SCORE 2 + static acpi_status acpi_dev_present(acpi_handle handle, u32 lvl_not_used, void *not_used, void **ret_p) { @@ -92,14 +95,17 @@ static acpi_status acpi_dev_present(acpi_handle handle, u32 lvl_not_used, return AE_OK; } -static bool acpi_extra_checks_passed(acpi_handle handle, bool is_bridge) +static int do_find_child_checks(acpi_handle handle, bool is_bridge) { + bool sta_present = true; 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; + status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); + if (status == AE_NOT_FOUND) + sta_present = false; + else if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED)) + return -ENODEV; if (is_bridge) { void *test = NULL; @@ -107,16 +113,17 @@ static bool acpi_extra_checks_passed(acpi_handle handle, bool is_bridge) /* 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; + if (!test) + return -ENODEV; } - return true; + return sta_present ? FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE; } struct find_child_context { u64 addr; bool is_bridge; acpi_handle ret; - bool ret_checked; + int ret_score; }; static acpi_status do_find_child(acpi_handle handle, u32 lvl_not_used, @@ -125,6 +132,7 @@ static acpi_status do_find_child(acpi_handle handle, u32 lvl_not_used, struct find_child_context *context = data; unsigned long long addr; acpi_status status; + int score; status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr); if (ACPI_FAILURE(status) || addr != context->addr) @@ -144,15 +152,20 @@ static acpi_status do_find_child(acpi_handle handle, u32 lvl_not_used, * 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)) + if (!context->ret_score) { + score = do_find_child_checks(context->ret, context->is_bridge); + if (score == FIND_CHILD_MAX_SCORE) return AE_CTRL_TERMINATE; else - context->ret_checked = true; + context->ret_score = score; } - if (acpi_extra_checks_passed(handle, context->is_bridge)) { + score = do_find_child_checks(handle, context->is_bridge); + if (score == FIND_CHILD_MAX_SCORE) { context->ret = handle; return AE_CTRL_TERMINATE; + } else if (score > context->ret_score) { + context->ret = handle; + context->ret_score = score; } return AE_OK; }