ACPI : Disable the device's ability to wake the sleeping system in the boot phase

In some machines some GPE is shared by several ACPI devices, for example:
sleep button, keyboard, mouse. At the same time one of them is
non-wake(runtime) device and the other are wake devices. In such case OSPM
should call the _PSW object to disable the device's ability to
wake the sleeping system in the boot phase.
Otherwise there will be ACPI interrupt flood triggered by the GPE input.

The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
So it is necessary to call _DSW object first. Only when it is not
present will the _PSW object used.

http://bugzilla.kernel.org/show_bug.cgi?id=10224

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Zhang Rui  <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 42 insertions, 1 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index e6ce262b5d44..bd32351854ac 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -692,6 +692,9 @@ static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
         acpi_status status = 0;
         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
         union acpi_object *package = NULL;
+        union acpi_object in_arg[3];
+        struct acpi_object_list arg_list = { 3, in_arg };
+        acpi_status psw_status = AE_OK;
 
         struct acpi_device_id button_device_ids[] = {
                 {"PNP0C0D", 0},
@@ -700,7 +703,6 @@ static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
                 {"", 0},
         };
 
-
         /* _PRW */
         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
         if (ACPI_FAILURE(status)) {
@@ -718,6 +720,45 @@ static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
         kfree(buffer.pointer);
 
         device->wakeup.flags.valid = 1;
+        /* Call _PSW/_DSW object to disable its ability to wake the sleeping
+         * system for the ACPI device with the _PRW object.
+         * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
+         * So it is necessary to call _DSW object first. Only when it is not
+         * present will the _PSW object used.
+         */
+        /*
+         * Three agruments are needed for the _DSW object.
+         * Argument 0: enable/disable the wake capabilities
+         * When _DSW object is called to disable the wake capabilities, maybe
+         * the first argument is filled. The value of the other two agruments
+         * is meaningless.
+         */
+        in_arg[0].type = ACPI_TYPE_INTEGER;
+        in_arg[0].integer.value = 0;
+        in_arg[1].type = ACPI_TYPE_INTEGER;
+        in_arg[1].integer.value = 0;
+        in_arg[2].type = ACPI_TYPE_INTEGER;
+        in_arg[2].integer.value = 0;
+        psw_status = acpi_evaluate_object(device->handle, "_DSW",
+                                                &arg_list, NULL);
+        if (ACPI_FAILURE(psw_status) && (psw_status != AE_NOT_FOUND))
+                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "error in evaluate _DSW\n"));
+        /*
+         * When the _DSW object is not present, OSPM will call _PSW object.
+         */
+        if (psw_status == AE_NOT_FOUND) {
+                /*
+                 * Only one agruments is required for the _PSW object.
+                 * agrument 0: enable/disable the wake capabilities
+                 */
+                arg_list.count = 1;
+                in_arg[0].integer.value = 0;
+                psw_status = acpi_evaluate_object(device->handle, "_PSW",
+                                                &arg_list, NULL);
+                if (ACPI_FAILURE(psw_status) && (psw_status != AE_NOT_FOUND))
+                        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "error in "
+                                                "evaluate _PSW\n"));
+        }
         /* Power button, Lid switch always enable wakeup */
         if (!acpi_match_device_ids(device, button_device_ids))
                 device->wakeup.flags.run_wake = 1;