Merge branch 'acpi-bind'

* acpi-bind:
  ACPI / bind: Prefer device objects with _STA to those without it

1 files changed, 24 insertions, 11 deletions

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;
 }