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path: root/drivers/acpi/acpica/evregion.c
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Diffstat (limited to 'drivers/acpi/acpica/evregion.c')
-rw-r--r--drivers/acpi/acpica/evregion.c795
1 files changed, 795 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/evregion.c b/drivers/acpi/acpica/evregion.c
new file mode 100644
index 000000000..2ba28a63f
--- /dev/null
+++ b/drivers/acpi/acpica/evregion.c
@@ -0,0 +1,795 @@
+/******************************************************************************
+ *
+ * Module Name: evregion - Operation Region support
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2015, 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("evregion")
+
+extern u8 acpi_gbl_default_address_spaces[];
+
+/* Local prototypes */
+
+static void
+acpi_ev_orphan_ec_reg_method(struct acpi_namespace_node *ec_device_node);
+
+static acpi_status
+acpi_ev_reg_run(acpi_handle obj_handle,
+ u32 level, void *context, void **return_value);
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_initialize_op_regions
+ *
+ * PARAMETERS: None
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Execute _REG methods for all Operation Regions that have
+ * an installed default region handler.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ev_initialize_op_regions(void)
+{
+ acpi_status status;
+ u32 i;
+
+ ACPI_FUNCTION_TRACE(ev_initialize_op_regions);
+
+ status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ /* Run the _REG methods for op_regions in each default address space */
+
+ for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++) {
+ /*
+ * Make sure the installed handler is the DEFAULT handler. If not the
+ * default, the _REG methods will have already been run (when the
+ * handler was installed)
+ */
+ if (acpi_ev_has_default_handler(acpi_gbl_root_node,
+ acpi_gbl_default_address_spaces
+ [i])) {
+ status =
+ acpi_ev_execute_reg_methods(acpi_gbl_root_node,
+ acpi_gbl_default_address_spaces
+ [i]);
+ }
+ }
+
+ acpi_gbl_reg_methods_executed = TRUE;
+
+ (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_address_space_dispatch
+ *
+ * PARAMETERS: region_obj - Internal region object
+ * field_obj - Corresponding field. Can be NULL.
+ * function - Read or Write operation
+ * region_offset - Where in the region to read or write
+ * bit_width - Field width in bits (8, 16, 32, or 64)
+ * value - Pointer to in or out value, must be
+ * a full 64-bit integer
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Dispatch an address space or operation region access to
+ * a previously installed handler.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj,
+ union acpi_operand_object *field_obj,
+ u32 function,
+ u32 region_offset, u32 bit_width, u64 *value)
+{
+ acpi_status status;
+ acpi_adr_space_handler handler;
+ acpi_adr_space_setup region_setup;
+ union acpi_operand_object *handler_desc;
+ union acpi_operand_object *region_obj2;
+ void *region_context = NULL;
+ struct acpi_connection_info *context;
+ acpi_physical_address address;
+
+ ACPI_FUNCTION_TRACE(ev_address_space_dispatch);
+
+ region_obj2 = acpi_ns_get_secondary_object(region_obj);
+ if (!region_obj2) {
+ return_ACPI_STATUS(AE_NOT_EXIST);
+ }
+
+ /* Ensure that there is a handler associated with this region */
+
+ handler_desc = region_obj->region.handler;
+ if (!handler_desc) {
+ ACPI_ERROR((AE_INFO,
+ "No handler for Region [%4.4s] (%p) [%s]",
+ acpi_ut_get_node_name(region_obj->region.node),
+ region_obj,
+ acpi_ut_get_region_name(region_obj->region.
+ space_id)));
+
+ return_ACPI_STATUS(AE_NOT_EXIST);
+ }
+
+ context = handler_desc->address_space.context;
+
+ /*
+ * It may be the case that the region has never been initialized.
+ * Some types of regions require special init code
+ */
+ if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
+
+ /* This region has not been initialized yet, do it */
+
+ region_setup = handler_desc->address_space.setup;
+ if (!region_setup) {
+
+ /* No initialization routine, exit with error */
+
+ ACPI_ERROR((AE_INFO,
+ "No init routine for region(%p) [%s]",
+ region_obj,
+ acpi_ut_get_region_name(region_obj->region.
+ space_id)));
+ return_ACPI_STATUS(AE_NOT_EXIST);
+ }
+
+ /*
+ * We must exit the interpreter because the region setup will
+ * potentially execute control methods (for example, the _REG method
+ * for this region)
+ */
+ acpi_ex_exit_interpreter();
+
+ status = region_setup(region_obj, ACPI_REGION_ACTIVATE,
+ context, &region_context);
+
+ /* Re-enter the interpreter */
+
+ acpi_ex_enter_interpreter();
+
+ /* Check for failure of the Region Setup */
+
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "During region initialization: [%s]",
+ acpi_ut_get_region_name(region_obj->
+ region.
+ space_id)));
+ return_ACPI_STATUS(status);
+ }
+
+ /* Region initialization may have been completed by region_setup */
+
+ if (!(region_obj->region.flags & AOPOBJ_SETUP_COMPLETE)) {
+ region_obj->region.flags |= AOPOBJ_SETUP_COMPLETE;
+
+ /*
+ * Save the returned context for use in all accesses to
+ * the handler for this particular region
+ */
+ if (!(region_obj2->extra.region_context)) {
+ region_obj2->extra.region_context =
+ region_context;
+ }
+ }
+ }
+
+ /* We have everything we need, we can invoke the address space handler */
+
+ handler = handler_desc->address_space.handler;
+ address = (region_obj->region.address + region_offset);
+
+ /*
+ * Special handling for generic_serial_bus and general_purpose_io:
+ * There are three extra parameters that must be passed to the
+ * handler via the context:
+ * 1) Connection buffer, a resource template from Connection() op
+ * 2) Length of the above buffer
+ * 3) Actual access length from the access_as() op
+ *
+ * In addition, for general_purpose_io, the Address and bit_width fields
+ * are defined as follows:
+ * 1) Address is the pin number index of the field (bit offset from
+ * the previous Connection)
+ * 2) bit_width is the actual bit length of the field (number of pins)
+ */
+ if ((region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS) &&
+ context && field_obj) {
+
+ /* Get the Connection (resource_template) buffer */
+
+ context->connection = field_obj->field.resource_buffer;
+ context->length = field_obj->field.resource_length;
+ context->access_length = field_obj->field.access_length;
+ }
+ if ((region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
+ context && field_obj) {
+
+ /* Get the Connection (resource_template) buffer */
+
+ context->connection = field_obj->field.resource_buffer;
+ context->length = field_obj->field.resource_length;
+ context->access_length = field_obj->field.access_length;
+ address = field_obj->field.pin_number_index;
+ bit_width = field_obj->field.bit_length;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
+ "Handler %p (@%p) Address %8.8X%8.8X [%s]\n",
+ &region_obj->region.handler->address_space, handler,
+ ACPI_FORMAT_UINT64(address),
+ acpi_ut_get_region_name(region_obj->region.
+ space_id)));
+
+ if (!(handler_desc->address_space.handler_flags &
+ ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
+ /*
+ * For handlers other than the default (supplied) handlers, we must
+ * exit the interpreter because the handler *might* block -- we don't
+ * know what it will do, so we can't hold the lock on the intepreter.
+ */
+ acpi_ex_exit_interpreter();
+ }
+
+ /* Call the handler */
+
+ status = handler(function, address, bit_width, value, context,
+ region_obj2->extra.region_context);
+
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
+ acpi_ut_get_region_name(region_obj->region.
+ space_id)));
+ }
+
+ if (!(handler_desc->address_space.handler_flags &
+ ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)) {
+ /*
+ * We just returned from a non-default handler, we must re-enter the
+ * interpreter
+ */
+ acpi_ex_enter_interpreter();
+ }
+
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_detach_region
+ *
+ * PARAMETERS: region_obj - Region Object
+ * acpi_ns_is_locked - Namespace Region Already Locked?
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Break the association between the handler and the region
+ * this is a two way association.
+ *
+ ******************************************************************************/
+
+void
+acpi_ev_detach_region(union acpi_operand_object *region_obj,
+ u8 acpi_ns_is_locked)
+{
+ union acpi_operand_object *handler_obj;
+ union acpi_operand_object *obj_desc;
+ union acpi_operand_object *start_desc;
+ union acpi_operand_object **last_obj_ptr;
+ acpi_adr_space_setup region_setup;
+ void **region_context;
+ union acpi_operand_object *region_obj2;
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE(ev_detach_region);
+
+ region_obj2 = acpi_ns_get_secondary_object(region_obj);
+ if (!region_obj2) {
+ return_VOID;
+ }
+ region_context = &region_obj2->extra.region_context;
+
+ /* Get the address handler from the region object */
+
+ handler_obj = region_obj->region.handler;
+ if (!handler_obj) {
+
+ /* This region has no handler, all done */
+
+ return_VOID;
+ }
+
+ /* Find this region in the handler's list */
+
+ obj_desc = handler_obj->address_space.region_list;
+ start_desc = obj_desc;
+ last_obj_ptr = &handler_obj->address_space.region_list;
+
+ while (obj_desc) {
+
+ /* Is this the correct Region? */
+
+ if (obj_desc == region_obj) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
+ "Removing Region %p from address handler %p\n",
+ region_obj, handler_obj));
+
+ /* This is it, remove it from the handler's list */
+
+ *last_obj_ptr = obj_desc->region.next;
+ obj_desc->region.next = NULL; /* Must clear field */
+
+ if (acpi_ns_is_locked) {
+ status =
+ acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+ if (ACPI_FAILURE(status)) {
+ return_VOID;
+ }
+ }
+
+ /* Now stop region accesses by executing the _REG method */
+
+ status =
+ acpi_ev_execute_reg_method(region_obj,
+ ACPI_REG_DISCONNECT);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "from region _REG, [%s]",
+ acpi_ut_get_region_name
+ (region_obj->region.space_id)));
+ }
+
+ if (acpi_ns_is_locked) {
+ status =
+ acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+ if (ACPI_FAILURE(status)) {
+ return_VOID;
+ }
+ }
+
+ /*
+ * If the region has been activated, call the setup handler with
+ * the deactivate notification
+ */
+ if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
+ region_setup = handler_obj->address_space.setup;
+ status =
+ region_setup(region_obj,
+ ACPI_REGION_DEACTIVATE,
+ handler_obj->address_space.
+ context, region_context);
+
+ /*
+ * region_context should have been released by the deactivate
+ * operation. We don't need access to it anymore here.
+ */
+ if (region_context) {
+ *region_context = NULL;
+ }
+
+ /* Init routine may fail, Just ignore errors */
+
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status,
+ "from region handler - deactivate, [%s]",
+ acpi_ut_get_region_name
+ (region_obj->region.
+ space_id)));
+ }
+
+ region_obj->region.flags &=
+ ~(AOPOBJ_SETUP_COMPLETE);
+ }
+
+ /*
+ * Remove handler reference in the region
+ *
+ * NOTE: this doesn't mean that the region goes away, the region
+ * is just inaccessible as indicated to the _REG method
+ *
+ * If the region is on the handler's list, this must be the
+ * region's handler
+ */
+ region_obj->region.handler = NULL;
+ acpi_ut_remove_reference(handler_obj);
+
+ return_VOID;
+ }
+
+ /* Walk the linked list of handlers */
+
+ last_obj_ptr = &obj_desc->region.next;
+ obj_desc = obj_desc->region.next;
+
+ /* Prevent infinite loop if list is corrupted */
+
+ if (obj_desc == start_desc) {
+ ACPI_ERROR((AE_INFO,
+ "Circular handler list in region object %p",
+ region_obj));
+ return_VOID;
+ }
+ }
+
+ /* If we get here, the region was not in the handler's region list */
+
+ ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
+ "Cannot remove region %p from address handler %p\n",
+ region_obj, handler_obj));
+
+ return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_attach_region
+ *
+ * PARAMETERS: handler_obj - Handler Object
+ * region_obj - Region Object
+ * acpi_ns_is_locked - Namespace Region Already Locked?
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Create the association between the handler and the region
+ * this is a two way association.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_attach_region(union acpi_operand_object *handler_obj,
+ union acpi_operand_object *region_obj,
+ u8 acpi_ns_is_locked)
+{
+
+ ACPI_FUNCTION_TRACE(ev_attach_region);
+
+ ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
+ "Adding Region [%4.4s] %p to address handler %p [%s]\n",
+ acpi_ut_get_node_name(region_obj->region.node),
+ region_obj, handler_obj,
+ acpi_ut_get_region_name(region_obj->region.
+ space_id)));
+
+ /* Link this region to the front of the handler's list */
+
+ region_obj->region.next = handler_obj->address_space.region_list;
+ handler_obj->address_space.region_list = region_obj;
+
+ /* Install the region's handler */
+
+ if (region_obj->region.handler) {
+ return_ACPI_STATUS(AE_ALREADY_EXISTS);
+ }
+
+ region_obj->region.handler = handler_obj;
+ acpi_ut_add_reference(handler_obj);
+
+ return_ACPI_STATUS(AE_OK);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_execute_reg_method
+ *
+ * PARAMETERS: region_obj - Region object
+ * function - Passed to _REG: On (1) or Off (0)
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Execute _REG method for a region
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_execute_reg_method(union acpi_operand_object *region_obj, u32 function)
+{
+ struct acpi_evaluate_info *info;
+ union acpi_operand_object *args[3];
+ union acpi_operand_object *region_obj2;
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE(ev_execute_reg_method);
+
+ region_obj2 = acpi_ns_get_secondary_object(region_obj);
+ if (!region_obj2) {
+ return_ACPI_STATUS(AE_NOT_EXIST);
+ }
+
+ if (region_obj2->extra.method_REG == NULL) {
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ /* Allocate and initialize the evaluation information block */
+
+ info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
+ if (!info) {
+ return_ACPI_STATUS(AE_NO_MEMORY);
+ }
+
+ info->prefix_node = region_obj2->extra.method_REG;
+ info->relative_pathname = NULL;
+ info->parameters = args;
+ info->flags = ACPI_IGNORE_RETURN_VALUE;
+
+ /*
+ * The _REG method has two arguments:
+ *
+ * arg0 - Integer:
+ * Operation region space ID Same value as region_obj->Region.space_id
+ *
+ * arg1 - Integer:
+ * connection status 1 for connecting the handler, 0 for disconnecting
+ * the handler (Passed as a parameter)
+ */
+ args[0] =
+ acpi_ut_create_integer_object((u64)region_obj->region.space_id);
+ if (!args[0]) {
+ status = AE_NO_MEMORY;
+ goto cleanup1;
+ }
+
+ args[1] = acpi_ut_create_integer_object((u64)function);
+ if (!args[1]) {
+ status = AE_NO_MEMORY;
+ goto cleanup2;
+ }
+
+ args[2] = NULL; /* Terminate list */
+
+ /* Execute the method, no return value */
+
+ ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
+ (ACPI_TYPE_METHOD, info->prefix_node, NULL));
+
+ status = acpi_ns_evaluate(info);
+ acpi_ut_remove_reference(args[1]);
+
+cleanup2:
+ acpi_ut_remove_reference(args[0]);
+
+cleanup1:
+ ACPI_FREE(info);
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_execute_reg_methods
+ *
+ * PARAMETERS: node - Namespace node for the device
+ * space_id - The address space ID
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Run all _REG methods for the input Space ID;
+ * Note: assumes namespace is locked, or system init time.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
+ acpi_adr_space_type space_id)
+{
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
+
+ /*
+ * Run all _REG methods for all Operation Regions for this space ID. This
+ * is a separate walk in order to handle any interdependencies between
+ * regions and _REG methods. (i.e. handlers must be installed for all
+ * regions of this Space ID before we can run any _REG methods)
+ */
+ status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
+ ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run,
+ NULL, &space_id, NULL);
+
+ /* Special case for EC: handle "orphan" _REG methods with no region */
+
+ if (space_id == ACPI_ADR_SPACE_EC) {
+ acpi_ev_orphan_ec_reg_method(node);
+ }
+
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_reg_run
+ *
+ * PARAMETERS: walk_namespace callback
+ *
+ * DESCRIPTION: Run _REG method for region objects of the requested spaceID
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_ev_reg_run(acpi_handle obj_handle,
+ u32 level, void *context, void **return_value)
+{
+ union acpi_operand_object *obj_desc;
+ struct acpi_namespace_node *node;
+ acpi_adr_space_type space_id;
+ acpi_status status;
+
+ space_id = *ACPI_CAST_PTR(acpi_adr_space_type, context);
+
+ /* Convert and validate the device handle */
+
+ node = acpi_ns_validate_handle(obj_handle);
+ if (!node) {
+ return (AE_BAD_PARAMETER);
+ }
+
+ /*
+ * We only care about regions.and objects that are allowed to have address
+ * space handlers
+ */
+ if ((node->type != ACPI_TYPE_REGION) && (node != acpi_gbl_root_node)) {
+ return (AE_OK);
+ }
+
+ /* Check for an existing internal object */
+
+ obj_desc = acpi_ns_get_attached_object(node);
+ if (!obj_desc) {
+
+ /* No object, just exit */
+
+ return (AE_OK);
+ }
+
+ /* Object is a Region */
+
+ if (obj_desc->region.space_id != space_id) {
+
+ /* This region is for a different address space, just ignore it */
+
+ return (AE_OK);
+ }
+
+ status = acpi_ev_execute_reg_method(obj_desc, ACPI_REG_CONNECT);
+ return (status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ev_orphan_ec_reg_method
+ *
+ * PARAMETERS: ec_device_node - Namespace node for an EC device
+ *
+ * RETURN: None
+ *
+ * DESCRIPTION: Execute an "orphan" _REG method that appears under the EC
+ * device. This is a _REG method that has no corresponding region
+ * within the EC device scope. The orphan _REG method appears to
+ * have been enabled by the description of the ECDT in the ACPI
+ * specification: "The availability of the region space can be
+ * detected by providing a _REG method object underneath the
+ * Embedded Controller device."
+ *
+ * To quickly access the EC device, we use the ec_device_node used
+ * during EC handler installation. Otherwise, we would need to
+ * perform a time consuming namespace walk, executing _HID
+ * methods to find the EC device.
+ *
+ * MUTEX: Assumes the namespace is locked
+ *
+ ******************************************************************************/
+
+static void
+acpi_ev_orphan_ec_reg_method(struct acpi_namespace_node *ec_device_node)
+{
+ acpi_handle reg_method;
+ struct acpi_namespace_node *next_node;
+ acpi_status status;
+ struct acpi_object_list args;
+ union acpi_object objects[2];
+
+ ACPI_FUNCTION_TRACE(ev_orphan_ec_reg_method);
+
+ if (!ec_device_node) {
+ return_VOID;
+ }
+
+ /* Namespace is currently locked, must release */
+
+ (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
+
+ /* Get a handle to a _REG method immediately under the EC device */
+
+ status = acpi_get_handle(ec_device_node, METHOD_NAME__REG, &reg_method);
+ if (ACPI_FAILURE(status)) {
+ goto exit; /* There is no _REG method present */
+ }
+
+ /*
+ * Execute the _REG method only if there is no Operation Region in
+ * this scope with the Embedded Controller space ID. Otherwise, it
+ * will already have been executed. Note, this allows for Regions
+ * with other space IDs to be present; but the code below will then
+ * execute the _REG method with the embedded_control space_ID argument.
+ */
+ next_node = acpi_ns_get_next_node(ec_device_node, NULL);
+ while (next_node) {
+ if ((next_node->type == ACPI_TYPE_REGION) &&
+ (next_node->object) &&
+ (next_node->object->region.space_id == ACPI_ADR_SPACE_EC)) {
+ goto exit; /* Do not execute the _REG */
+ }
+
+ next_node = acpi_ns_get_next_node(ec_device_node, next_node);
+ }
+
+ /* Evaluate the _REG(embedded_control,Connect) method */
+
+ args.count = 2;
+ args.pointer = objects;
+ objects[0].type = ACPI_TYPE_INTEGER;
+ objects[0].integer.value = ACPI_ADR_SPACE_EC;
+ objects[1].type = ACPI_TYPE_INTEGER;
+ objects[1].integer.value = ACPI_REG_CONNECT;
+
+ status = acpi_evaluate_object(reg_method, NULL, &args, NULL);
+
+exit:
+ /* We ignore all errors from above, don't care */
+
+ status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+ return_VOID;
+}