Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 882 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/evregion.c b/drivers/acpi/acpica/evregion.c
new file mode 100644
index 0000000000..18fdf2bc2d
--- /dev/null
+++ b/drivers/acpi/acpica/evregion.c
@@ -0,0 +1,882 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: evregion - Operation Region support
+ *
+ * Copyright (C) 2000 - 2023, Intel Corp.
+ *
+ *****************************************************************************/
+
+#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_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
+				  acpi_adr_space_type space_id);
+
+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])) {
+			acpi_ev_execute_reg_methods(acpi_gbl_root_node,
+						    acpi_gbl_default_address_spaces
+						    [i], ACPI_REG_CONNECT);
+		}
+	}
+
+	(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.
+ *
+ * NOTE: During early initialization, we always install the default region
+ * handlers for Memory, I/O and PCI_Config. This ensures that these operation
+ * region address spaces are always available as per the ACPI specification.
+ * This is especially needed in order to support the execution of
+ * module-level AML code during loading of the ACPI tables.
+ *
+ ******************************************************************************/
+
+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_mutex context_mutex;
+	u8 context_locked;
+	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;
+	context_mutex = handler_desc->address_space.context_mutex;
+	context_locked = FALSE;
+
+	/*
+	 * 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);
+		}
+
+		if (region_obj->region.space_id == ACPI_ADR_SPACE_PLATFORM_COMM) {
+			struct acpi_pcc_info *ctx =
+			    handler_desc->address_space.context;
+
+			ctx->internal_buffer =
+			    field_obj->field.internal_pcc_buffer;
+			ctx->length = (u16)region_obj->region.length;
+			ctx->subspace_id = (u8)region_obj->region.address;
+		}
+
+		if (region_obj->region.space_id ==
+		    ACPI_ADR_SPACE_FIXED_HARDWARE) {
+			struct acpi_ffh_info *ctx =
+			    handler_desc->address_space.context;
+
+			ctx->length = region_obj->region.length;
+			ctx->offset = region_obj->region.address;
+		}
+
+		/*
+		 * 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);
+
+	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 interpreter.
+		 */
+		acpi_ex_exit_interpreter();
+	}
+
+	/*
+	 * 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
+	 *
+	 * Since we pass these extra parameters via the context, which is
+	 * shared between threads, we must lock the context to avoid these
+	 * parameters being changed from another thread before the handler
+	 * has completed running.
+	 *
+	 * 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 ||
+	     region_obj->region.space_id == ACPI_ADR_SPACE_GPIO) &&
+	    context && field_obj) {
+
+		status =
+		    acpi_os_acquire_mutex(context_mutex, ACPI_WAIT_FOREVER);
+		if (ACPI_FAILURE(status)) {
+			goto re_enter_interpreter;
+		}
+
+		context_locked = TRUE;
+
+		/* 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) {
+			address = field_obj->field.pin_number_index;
+			bit_width = field_obj->field.bit_length;
+		}
+	}
+
+	/* Call the handler */
+
+	status = handler(function, address, bit_width, value, context,
+			 region_obj2->extra.region_context);
+
+	if (context_locked) {
+		acpi_os_release_mutex(context_mutex);
+	}
+
+	if (ACPI_FAILURE(status)) {
+		ACPI_EXCEPTION((AE_INFO, status, "Returned by Handler for [%s]",
+				acpi_ut_get_region_name(region_obj->region.
+							space_id)));
+
+		/*
+		 * Special case for an EC timeout. These are seen so frequently
+		 * that an additional error message is helpful
+		 */
+		if ((region_obj->region.space_id == ACPI_ADR_SPACE_EC) &&
+		    (status == AE_TIME)) {
+			ACPI_ERROR((AE_INFO,
+				    "Timeout from EC hardware or EC device driver"));
+		}
+	}
+
+re_enter_interpreter:
+	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);
+
+	/* Install the region's handler */
+
+	if (region_obj->region.handler) {
+		return_ACPI_STATUS(AE_ALREADY_EXISTS);
+	}
+
+	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;
+	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;
+	const acpi_name *reg_name_ptr =
+	    ACPI_CAST_PTR(acpi_name, METHOD_NAME__REG);
+	struct acpi_namespace_node *method_node;
+	struct acpi_namespace_node *node;
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE(ev_execute_reg_method);
+
+	if (!acpi_gbl_namespace_initialized ||
+	    region_obj->region.handler == NULL) {
+		return_ACPI_STATUS(AE_OK);
+	}
+
+	region_obj2 = acpi_ns_get_secondary_object(region_obj);
+	if (!region_obj2) {
+		return_ACPI_STATUS(AE_NOT_EXIST);
+	}
+
+	/*
+	 * Find any "_REG" method associated with this region definition.
+	 * The method should always be updated as this function may be
+	 * invoked after a namespace change.
+	 */
+	node = region_obj->region.node->parent;
+	status =
+	    acpi_ns_search_one_scope(*reg_name_ptr, node, ACPI_TYPE_METHOD,
+				     &method_node);
+	if (ACPI_SUCCESS(status)) {
+		/*
+		 * The _REG method is optional and there can be only one per
+		 * region definition. This will be executed when the handler is
+		 * attached or removed.
+		 */
+		region_obj2->extra.method_REG = method_node;
+	}
+	if (region_obj2->extra.method_REG == NULL) {
+		return_ACPI_STATUS(AE_OK);
+	}
+
+	/* _REG(DISCONNECT) should be paired with _REG(CONNECT) */
+
+	if ((function == ACPI_REG_CONNECT &&
+	     region_obj->common.flags & AOPOBJ_REG_CONNECTED) ||
+	    (function == ACPI_REG_DISCONNECT &&
+	     !(region_obj->common.flags & AOPOBJ_REG_CONNECTED))) {
+		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]);
+
+	if (ACPI_FAILURE(status)) {
+		goto cleanup2;
+	}
+
+	if (function == ACPI_REG_CONNECT) {
+		region_obj->common.flags |= AOPOBJ_REG_CONNECTED;
+	} else {
+		region_obj->common.flags &= ~AOPOBJ_REG_CONNECTED;
+	}
+
+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
+ *              function        - Passed to _REG: On (1) or Off (0)
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Run all _REG methods for the input Space ID;
+ *              Note: assumes namespace is locked, or system init time.
+ *
+ ******************************************************************************/
+
+void
+acpi_ev_execute_reg_methods(struct acpi_namespace_node *node,
+			    acpi_adr_space_type space_id, u32 function)
+{
+	struct acpi_reg_walk_info info;
+
+	ACPI_FUNCTION_TRACE(ev_execute_reg_methods);
+
+	/*
+	 * These address spaces do not need a call to _REG, since the ACPI
+	 * specification defines them as: "must always be accessible". Since
+	 * they never change state (never become unavailable), no need to ever
+	 * call _REG on them. Also, a data_table is not a "real" address space,
+	 * so do not call _REG. September 2018.
+	 */
+	if ((space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) ||
+	    (space_id == ACPI_ADR_SPACE_SYSTEM_IO) ||
+	    (space_id == ACPI_ADR_SPACE_DATA_TABLE)) {
+		return_VOID;
+	}
+
+	info.space_id = space_id;
+	info.function = function;
+	info.reg_run_count = 0;
+
+	ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
+			      "    Running _REG methods for SpaceId %s\n",
+			      acpi_ut_get_region_name(info.space_id)));
+
+	/*
+	 * 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)
+	 */
+	(void)acpi_ns_walk_namespace(ACPI_TYPE_ANY, node, ACPI_UINT32_MAX,
+				     ACPI_NS_WALK_UNLOCK, acpi_ev_reg_run, NULL,
+				     &info, NULL);
+
+	/*
+	 * Special case for EC and GPIO: handle "orphan" _REG methods with
+	 * no region.
+	 */
+	if (space_id == ACPI_ADR_SPACE_EC || space_id == ACPI_ADR_SPACE_GPIO) {
+		acpi_ev_execute_orphan_reg_method(node, space_id);
+	}
+
+	ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES,
+			      "    Executed %u _REG methods for SpaceId %s\n",
+			      info.reg_run_count,
+			      acpi_ut_get_region_name(info.space_id)));
+
+	return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * 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_status status;
+	struct acpi_reg_walk_info *info;
+
+	info = ACPI_CAST_PTR(struct acpi_reg_walk_info, 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 != info->space_id) {
+
+		/* This region is for a different address space, just ignore it */
+
+		return (AE_OK);
+	}
+
+	info->reg_run_count++;
+	status = acpi_ev_execute_reg_method(obj_desc, info->function);
+	return (status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ev_execute_orphan_reg_method
+ *
+ * PARAMETERS:  device_node         - Namespace node for an ACPI device
+ *              space_id            - The address space ID
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Execute an "orphan" _REG method that appears under an ACPI
+ *              device. This is a _REG method that has no corresponding region
+ *              within the device's scope. ACPI tables depending on these
+ *              "orphan" _REG methods have been seen for both EC and GPIO
+ *              Operation Regions. Presumably the Windows ACPI implementation
+ *              always calls the _REG method independent of the presence of
+ *              an actual Operation Region with the correct address space ID.
+ *
+ *  MUTEX:      Assumes the namespace is locked
+ *
+ ******************************************************************************/
+
+static void
+acpi_ev_execute_orphan_reg_method(struct acpi_namespace_node *device_node,
+				  acpi_adr_space_type space_id)
+{
+	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_execute_orphan_reg_method);
+
+	if (!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(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(device_node, NULL);
+	while (next_node) {
+		if ((next_node->type == ACPI_TYPE_REGION) &&
+		    (next_node->object) &&
+		    (next_node->object->region.space_id == space_id)) {
+			goto exit;	/* Do not execute the _REG */
+		}
+
+		next_node = acpi_ns_get_next_node(device_node, next_node);
+	}
+
+	/* Evaluate the _REG(space_id,Connect) method */
+
+	args.count = 2;
+	args.pointer = objects;
+	objects[0].type = ACPI_TYPE_INTEGER;
+	objects[0].integer.value = space_id;
+	objects[1].type = ACPI_TYPE_INTEGER;
+	objects[1].integer.value = ACPI_REG_CONNECT;
+
+	(void)acpi_evaluate_object(reg_method, NULL, &args, NULL);
+
+exit:
+	/* We ignore all errors from above, don't care */
+
+	(void)acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
+	return_VOID;
+}