aboutsummaryrefslogtreecommitdiff
path: root/drivers/acpi/acpica/evgpeinit.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/acpi/acpica/evgpeinit.c')
-rw-r--r--drivers/acpi/acpica/evgpeinit.c653
1 files changed, 653 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/evgpeinit.c b/drivers/acpi/acpica/evgpeinit.c
new file mode 100644
index 00000000000..3f6c2d26410
--- /dev/null
+++ b/drivers/acpi/acpica/evgpeinit.c
@@ -0,0 +1,653 @@
+/******************************************************************************
+ *
+ * Module Name: evgpeinit - System GPE initialization and update
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2010, Intel Corp.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions, and the following disclaimer,
+ * without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ * substantially similar to the "NO WARRANTY" disclaimer below
+ * ("Disclaimer") and any redistribution must be conditioned upon
+ * including a substantially similar Disclaimer requirement for further
+ * binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ * of any contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ */
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acevents.h"
+#include "acnamesp.h"
+#include "acinterp.h"
+
+#define _COMPONENT ACPI_EVENTS
+ACPI_MODULE_NAME("evgpeinit")
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_gpe_initialize
+ *
+ * PARAMETERS: None
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
+ *
+ ******************************************************************************/
+acpi_status acpi_ev_gpe_initialize(void)
+{
+ u32 register_count0 = 0;
+ u32 register_count1 = 0;
+ u32 gpe_number_max = 0;
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE(ev_gpe_initialize);
+
+ status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ /*
+ * Initialize the GPE Block(s) defined in the FADT
+ *
+ * Why the GPE register block lengths are divided by 2: From the ACPI
+ * Spec, section "General-Purpose Event Registers", we have:
+ *
+ * "Each register block contains two registers of equal length
+ * GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
+ * GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
+ * The length of the GPE1_STS and GPE1_EN registers is equal to
+ * half the GPE1_LEN. If a generic register block is not supported
+ * then its respective block pointer and block length values in the
+ * FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
+ * to be the same size."
+ */
+
+ /*
+ * Determine the maximum GPE number for this machine.
+ *
+ * Note: both GPE0 and GPE1 are optional, and either can exist without
+ * the other.
+ *
+ * If EITHER the register length OR the block address are zero, then that
+ * particular block is not supported.
+ */
+ if (acpi_gbl_FADT.gpe0_block_length &&
+ acpi_gbl_FADT.xgpe0_block.address) {
+
+ /* GPE block 0 exists (has both length and address > 0) */
+
+ register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
+
+ gpe_number_max =
+ (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
+
+ /* Install GPE Block 0 */
+
+ status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
+ &acpi_gbl_FADT.xgpe0_block,
+ register_count0, 0,
+ acpi_gbl_FADT.sci_interrupt,
+ &acpi_gbl_gpe_fadt_blocks[0]);
+
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "Could not create GPE Block 0"));
+ }
+ }
+
+ if (acpi_gbl_FADT.gpe1_block_length &&
+ acpi_gbl_FADT.xgpe1_block.address) {
+
+ /* GPE block 1 exists (has both length and address > 0) */
+
+ register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
+
+ /* Check for GPE0/GPE1 overlap (if both banks exist) */
+
+ if ((register_count0) &&
+ (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
+ ACPI_ERROR((AE_INFO,
+ "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
+ "(GPE %u to %u) - Ignoring GPE1",
+ gpe_number_max, acpi_gbl_FADT.gpe1_base,
+ acpi_gbl_FADT.gpe1_base +
+ ((register_count1 *
+ ACPI_GPE_REGISTER_WIDTH) - 1)));
+
+ /* Ignore GPE1 block by setting the register count to zero */
+
+ register_count1 = 0;
+ } else {
+ /* Install GPE Block 1 */
+
+ status =
+ acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
+ &acpi_gbl_FADT.xgpe1_block,
+ register_count1,
+ acpi_gbl_FADT.gpe1_base,
+ acpi_gbl_FADT.
+ sci_interrupt,
+ &acpi_gbl_gpe_fadt_blocks
+ [1]);
+
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "Could not create GPE Block 1"));
+ }
+
+ /*
+ * GPE0 and GPE1 do not have to be contiguous in the GPE number
+ * space. However, GPE0 always starts at GPE number zero.
+ */
+ gpe_number_max = acpi_gbl_FADT.gpe1_base +
+ ((register_count1 * ACPI_GPE_REGISTER_WIDTH) - 1);
+ }
+ }
+
+ /* Exit if there are no GPE registers */
+
+ if ((register_count0 + register_count1) == 0) {
+
+ /* GPEs are not required by ACPI, this is OK */
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INIT,
+ "There are no GPE blocks defined in the FADT\n"));
+ status = AE_OK;
+ goto cleanup;
+ }
+
+ /* Check for Max GPE number out-of-range */
+
+ if (gpe_number_max > ACPI_GPE_MAX) {
+ ACPI_ERROR((AE_INFO,
+ "Maximum GPE number from FADT is too large: 0x%X",
+ gpe_number_max));
+ status = AE_BAD_VALUE;
+ goto cleanup;
+ }
+
+ cleanup:
+ (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+ return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_update_gpes
+ *
+ * PARAMETERS: table_owner_id - ID of the newly-loaded ACPI table
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
+ * result of a Load() or load_table() operation. If new GPE
+ * methods have been installed, register the new methods and
+ * enable and runtime GPEs that are associated with them. Also,
+ * run any newly loaded _PRW methods in order to discover any
+ * new CAN_WAKE GPEs.
+ *
+ ******************************************************************************/
+
+void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
+{
+ struct acpi_gpe_xrupt_info *gpe_xrupt_info;
+ struct acpi_gpe_block_info *gpe_block;
+ struct acpi_gpe_walk_info walk_info;
+ acpi_status status = AE_OK;
+ u32 new_wake_gpe_count = 0;
+
+ /* We will examine only _PRW/_Lxx/_Exx methods owned by this table */
+
+ walk_info.owner_id = table_owner_id;
+ walk_info.execute_by_owner_id = TRUE;
+ walk_info.count = 0;
+
+ if (acpi_gbl_leave_wake_gpes_disabled) {
+ /*
+ * 1) Run any newly-loaded _PRW methods to find any GPEs that
+ * can now be marked as CAN_WAKE GPEs. Note: We must run the
+ * _PRW methods before we process the _Lxx/_Exx methods because
+ * we will enable all runtime GPEs associated with the new
+ * _Lxx/_Exx methods at the time we process those methods.
+ *
+ * Unlock interpreter so that we can run the _PRW methods.
+ */
+ walk_info.gpe_block = NULL;
+ walk_info.gpe_device = NULL;
+
+ acpi_ex_exit_interpreter();
+
+ status =
+ acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+ ACPI_UINT32_MAX,
+ ACPI_NS_WALK_NO_UNLOCK,
+ acpi_ev_match_prw_and_gpe, NULL,
+ &walk_info, NULL);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "While executing _PRW methods"));
+ }
+
+ acpi_ex_enter_interpreter();
+ new_wake_gpe_count = walk_info.count;
+ }
+
+ /*
+ * 2) Find any _Lxx/_Exx GPE methods that have just been loaded.
+ *
+ * Any GPEs that correspond to new _Lxx/_Exx methods and are not
+ * marked as CAN_WAKE are immediately enabled.
+ *
+ * Examine the namespace underneath each gpe_device within the
+ * gpe_block lists.
+ */
+ status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
+ if (ACPI_FAILURE(status)) {
+ return;
+ }
+
+ walk_info.count = 0;
+ walk_info.enable_this_gpe = TRUE;
+
+ /* Walk the interrupt level descriptor list */
+
+ gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
+ while (gpe_xrupt_info) {
+
+ /* Walk all Gpe Blocks attached to this interrupt level */
+
+ gpe_block = gpe_xrupt_info->gpe_block_list_head;
+ while (gpe_block) {
+ walk_info.gpe_block = gpe_block;
+ walk_info.gpe_device = gpe_block->node;
+
+ status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
+ walk_info.gpe_device,
+ ACPI_UINT32_MAX,
+ ACPI_NS_WALK_NO_UNLOCK,
+ acpi_ev_match_gpe_method,
+ NULL, &walk_info, NULL);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "While decoding _Lxx/_Exx methods"));
+ }
+
+ gpe_block = gpe_block->next;
+ }
+
+ gpe_xrupt_info = gpe_xrupt_info->next;
+ }
+
+ if (walk_info.count || new_wake_gpe_count) {
+ ACPI_INFO((AE_INFO,
+ "Enabled %u new runtime GPEs, added %u new wakeup GPEs",
+ walk_info.count, new_wake_gpe_count));
+ }
+
+ (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
+ return;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_match_gpe_method
+ *
+ * PARAMETERS: Callback from walk_namespace
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
+ * control method under the _GPE portion of the namespace.
+ * Extract the name and GPE type from the object, saving this
+ * information for quick lookup during GPE dispatch. Allows a
+ * per-owner_id evaluation if execute_by_owner_id is TRUE in the
+ * walk_info parameter block.
+ *
+ * The name of each GPE control method is of the form:
+ * "_Lxx" or "_Exx", where:
+ * L - means that the GPE is level triggered
+ * E - means that the GPE is edge triggered
+ * 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.
+ * If walk_info->enable_this_gpe is TRUE, the GPE that is referred to by a GPE
+ * method is immediately enabled (Used for Load/load_table operators)
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_match_gpe_method(acpi_handle obj_handle,
+ u32 level, void *context, void **return_value)
+{
+ struct acpi_namespace_node *method_node =
+ ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
+ struct acpi_gpe_walk_info *walk_info =
+ ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
+ struct acpi_gpe_event_info *gpe_event_info;
+ struct acpi_namespace_node *gpe_device;
+ acpi_status status;
+ u32 gpe_number;
+ char name[ACPI_NAME_SIZE + 1];
+ u8 type;
+
+ ACPI_FUNCTION_TRACE(ev_match_gpe_method);
+
+ /* Check if requested owner_id matches this owner_id */
+
+ if ((walk_info->execute_by_owner_id) &&
+ (method_node->owner_id != walk_info->owner_id)) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /*
+ * Match and decode the _Lxx and _Exx GPE method names
+ *
+ * 1) Extract the method name and null terminate it
+ */
+ ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
+ name[ACPI_NAME_SIZE] = 0;
+
+ /* 2) Name must begin with an underscore */
+
+ if (name[0] != '_') {
+ return_ACPI_STATUS(AE_OK); /* Ignore this method */
+ }
+
+ /*
+ * 3) Edge/Level determination is based on the 2nd character
+ * of the method name
+ *
+ * NOTE: Default GPE type is RUNTIME only. Later, if a _PRW object is
+ * found that points to this GPE, the ACPI_GPE_CAN_WAKE flag is set.
+ */
+ switch (name[1]) {
+ case 'L':
+ type = ACPI_GPE_LEVEL_TRIGGERED;
+ break;
+
+ case 'E':
+ type = ACPI_GPE_EDGE_TRIGGERED;
+ break;
+
+ default:
+ /* Unknown method type, just ignore it */
+
+ ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
+ "Ignoring unknown GPE method type: %s "
+ "(name not of form _Lxx or _Exx)", name));
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /* 4) The last two characters of the name are the hex GPE Number */
+
+ gpe_number = ACPI_STRTOUL(&name[2], NULL, 16);
+ if (gpe_number == ACPI_UINT32_MAX) {
+
+ /* Conversion failed; invalid method, just ignore it */
+
+ ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
+ "Could not extract GPE number from name: %s "
+ "(name is not of form _Lxx or _Exx)", name));
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /* Ensure that we have a valid GPE number for this GPE block */
+
+ gpe_event_info =
+ acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
+ if (!gpe_event_info) {
+ /*
+ * This gpe_number is not valid for this GPE block, just ignore it.
+ * However, it may be valid for a different GPE block, since GPE0
+ * and GPE1 methods both appear under \_GPE.
+ */
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
+ ACPI_GPE_DISPATCH_HANDLER) {
+
+ /* If there is already a handler, ignore this GPE method */
+
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
+ ACPI_GPE_DISPATCH_METHOD) {
+ /*
+ * If there is already a method, ignore this method. But check
+ * for a type mismatch (if both the _Lxx AND _Exx exist)
+ */
+ if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
+ ACPI_ERROR((AE_INFO,
+ "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
+ gpe_number, gpe_number, gpe_number));
+ }
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /*
+ * Add the GPE information from above to the gpe_event_info block for
+ * use during dispatch of this GPE.
+ */
+ gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
+ gpe_event_info->dispatch.method_node = method_node;
+
+ /*
+ * Enable this GPE if requested. This only happens when during the
+ * execution of a Load or load_table operator. We have found a new
+ * GPE method and want to immediately enable the GPE if it is a
+ * runtime GPE.
+ */
+ if (walk_info->enable_this_gpe) {
+
+ /* Ignore GPEs that can wake the system */
+
+ if (!(gpe_event_info->flags & ACPI_GPE_CAN_WAKE) ||
+ !acpi_gbl_leave_wake_gpes_disabled) {
+ walk_info->count++;
+ gpe_device = walk_info->gpe_device;
+
+ if (gpe_device == acpi_gbl_fadt_gpe_device) {
+ gpe_device = NULL;
+ }
+
+ status = acpi_enable_gpe(gpe_device, gpe_number,
+ ACPI_GPE_TYPE_RUNTIME);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "Could not enable GPE 0x%02X",
+ gpe_number));
+ }
+ }
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
+ "Registered GPE method %s as GPE number 0x%.2X\n",
+ name, gpe_number));
+ return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_match_prw_and_gpe
+ *
+ * PARAMETERS: Callback from walk_namespace
+ *
+ * RETURN: Status. NOTE: We ignore errors so that the _PRW walk is
+ * not aborted on a single _PRW failure.
+ *
+ * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
+ * Device. Run the _PRW method. If present, extract the GPE
+ * number and mark the GPE as a CAN_WAKE GPE. Allows a
+ * per-owner_id execution if execute_by_owner_id is TRUE in the
+ * walk_info parameter block.
+ *
+ * If walk_info->execute_by_owner_id is TRUE, we only execute _PRWs with that
+ * owner.
+ * If walk_info->gpe_device is NULL, we execute every _PRW found. Otherwise,
+ * we only execute _PRWs that refer to the input gpe_device.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_match_prw_and_gpe(acpi_handle obj_handle,
+ u32 level, void *context, void **return_value)
+{
+ struct acpi_gpe_walk_info *walk_info =
+ ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
+ struct acpi_namespace_node *gpe_device;
+ struct acpi_gpe_block_info *gpe_block;
+ struct acpi_namespace_node *target_gpe_device;
+ struct acpi_namespace_node *prw_node;
+ struct acpi_gpe_event_info *gpe_event_info;
+ union acpi_operand_object *pkg_desc;
+ union acpi_operand_object *obj_desc;
+ u32 gpe_number;
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE(ev_match_prw_and_gpe);
+
+ /* Check for a _PRW method under this device */
+
+ status = acpi_ns_get_node(obj_handle, METHOD_NAME__PRW,
+ ACPI_NS_NO_UPSEARCH, &prw_node);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /* Check if requested owner_id matches this owner_id */
+
+ if ((walk_info->execute_by_owner_id) &&
+ (prw_node->owner_id != walk_info->owner_id)) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /* Execute the _PRW */
+
+ status = acpi_ut_evaluate_object(prw_node, NULL,
+ ACPI_BTYPE_PACKAGE, &pkg_desc);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /* The returned _PRW package must have at least two elements */
+
+ if (pkg_desc->package.count < 2) {
+ goto cleanup;
+ }
+
+ /* Extract pointers from the input context */
+
+ gpe_device = walk_info->gpe_device;
+ gpe_block = walk_info->gpe_block;
+
+ /*
+ * The _PRW object must return a package, we are only interested
+ * in the first element
+ */
+ obj_desc = pkg_desc->package.elements[0];
+
+ if (obj_desc->common.type == ACPI_TYPE_INTEGER) {
+
+ /* Use FADT-defined GPE device (from definition of _PRW) */
+
+ target_gpe_device = NULL;
+ if (gpe_device) {
+ target_gpe_device = acpi_gbl_fadt_gpe_device;
+ }
+
+ /* Integer is the GPE number in the FADT described GPE blocks */
+
+ gpe_number = (u32)obj_desc->integer.value;
+ } else if (obj_desc->common.type == ACPI_TYPE_PACKAGE) {
+
+ /* Package contains a GPE reference and GPE number within a GPE block */
+
+ if ((obj_desc->package.count < 2) ||
+ ((obj_desc->package.elements[0])->common.type !=
+ ACPI_TYPE_LOCAL_REFERENCE) ||
+ ((obj_desc->package.elements[1])->common.type !=
+ ACPI_TYPE_INTEGER)) {
+ goto cleanup;
+ }
+
+ /* Get GPE block reference and decode */
+
+ target_gpe_device =
+ obj_desc->package.elements[0]->reference.node;
+ gpe_number = (u32)obj_desc->package.elements[1]->integer.value;
+ } else {
+ /* Unknown type, just ignore it */
+
+ goto cleanup;
+ }
+
+ /* Get the gpe_event_info for this GPE */
+
+ if (gpe_device) {
+ /*
+ * Is this GPE within this block?
+ *
+ * TRUE if and only if these conditions are true:
+ * 1) The GPE devices match.
+ * 2) The GPE index(number) is within the range of the Gpe Block
+ * associated with the GPE device.
+ */
+ if (gpe_device != target_gpe_device) {
+ goto cleanup;
+ }
+
+ gpe_event_info =
+ acpi_ev_low_get_gpe_info(gpe_number, gpe_block);
+ } else {
+ /* gpe_device is NULL, just match the target_device and gpe_number */
+
+ gpe_event_info =
+ acpi_ev_get_gpe_event_info(target_gpe_device, gpe_number);
+ }
+
+ if (gpe_event_info) {
+ if (!(gpe_event_info->flags & ACPI_GPE_CAN_WAKE)) {
+
+ /* This GPE can wake the system */
+
+ gpe_event_info->flags |= ACPI_GPE_CAN_WAKE;
+ walk_info->count++;
+ }
+ }
+
+ cleanup:
+ acpi_ut_remove_reference(pkg_desc);
+ return_ACPI_STATUS(AE_OK);
+}