1 files changed, 24 insertions, 11 deletions

diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
index 9467229..10f0f40 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;
 }