Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / drivers / acpi / acpica / evgpeinit.c

diff --git a/drivers/acpi/acpica/evgpeinit.c b/drivers/acpi/acpica/evgpeinit.c
index 4c8dea513b66adeea7881d7f541237c812e5bf14..ce9aa9f9a9724e818d5d6e6fe568e35a3bf9d39c 100644 (file)
--- a/drivers/acpi/acpica/evgpeinit.c
+++ b/drivers/acpi/acpica/evgpeinit.c
@@ -5,7 +5,7 @@
  *****************************************************************************/
 
 /*
- * Copyright (C) 2000 - 2010, Intel Corp.
+ * Copyright (C) 2000 - 2011, Intel Corp.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -45,11 +45,27 @@
 #include "accommon.h"
 #include "acevents.h"
 #include "acnamesp.h"
-#include "acinterp.h"
 
 #define _COMPONENT          ACPI_EVENTS
 ACPI_MODULE_NAME("evgpeinit")
 
+/*
+ * Note: History of _PRW support in ACPICA
+ *
+ * Originally (2000 - 2010), the GPE initialization code performed a walk of
+ * the entire namespace to execute the _PRW methods and detect all GPEs
+ * capable of waking the system.
+ *
+ * As of 10/2010, the _PRW method execution has been removed since it is
+ * actually unnecessary. The host OS must in fact execute all _PRW methods
+ * in order to identify the device/power-resource dependencies. We now put
+ * the onus on the host OS to identify the wake GPEs as part of this process
+ * and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This
+ * not only reduces the complexity of the ACPICA initialization code, but in
+ * some cases (on systems with very large namespaces) it should reduce the
+ * kernel boot time as well.
+ */
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ev_gpe_initialize
@@ -222,7 +238,7 @@ void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
        acpi_status status = AE_OK;
 
        /*
-        * 2) Find any _Lxx/_Exx GPE methods that have just been loaded.
+        * Find any _Lxx/_Exx GPE methods that have just been loaded.
         *
         * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
         * enabled.
@@ -235,9 +251,9 @@ void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
                return;
        }
 
+       walk_info.count = 0;
        walk_info.owner_id = table_owner_id;
        walk_info.execute_by_owner_id = TRUE;
-       walk_info.count = 0;
 
        /* Walk the interrupt level descriptor list */
 
@@ -298,7 +314,7 @@ void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
  *                  xx     - is the GPE number [in HEX]
  *
  * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
- *    with that owner.
+ * with that owner.
  *
  ******************************************************************************/
 
@@ -415,6 +431,7 @@ acpi_ev_match_gpe_method(acpi_handle obj_handle,
         * Add the GPE information from above to the gpe_event_info block for
         * use during dispatch of this GPE.
         */
+       gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
        gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
        gpe_event_info->dispatch.method_node = method_node;