// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: evxfregn - External Interfaces, ACPI Operation Regions and
 *                         Address Spaces.
 *
 * Copyright (C) 2000 - 2025, Intel Corp.
 *
 *****************************************************************************/

#define EXPORT_ACPI_INTERFACES

#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acevents.h"

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evxfregn")

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_address_space_handler_internal
 *
 * PARAMETERS:  device          - Handle for the device
 *              space_id        - The address space ID
 *              handler         - Address of the handler
 *              setup           - Address of the setup function
 *              context         - Value passed to the handler on each access
 *              Run_reg         - Run _REG methods for this address space?
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install a handler for all op_regions of a given space_id.
 *
 * NOTE: This function should only be called after acpi_enable_subsystem has
 * been called. This is because any _REG methods associated with the Space ID
 * are executed here, and these methods can only be safely executed after
 * the default handlers have been installed and the hardware has been
 * initialized (via acpi_enable_subsystem.)
 * To avoid this problem pass FALSE for Run_Reg and later on call
 * acpi_execute_reg_methods() to execute _REG.
 *
 ******************************************************************************/
static acpi_status
acpi_install_address_space_handler_internal(acpi_handle device,
                                            acpi_adr_space_type space_id,
                                            acpi_adr_space_handler handler,
                                            acpi_adr_space_setup setup,
                                            void *context, u8 run_reg)
{
        struct acpi_namespace_node *node;
        acpi_status status;

        ACPI_FUNCTION_TRACE(acpi_install_address_space_handler);

        /* Parameter validation */

        if (!device) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Convert and validate the device handle */

        node = acpi_ns_validate_handle(device);
        if (!node) {
                status = AE_BAD_PARAMETER;
                goto unlock_and_exit;
        }

        /* Install the handler for all Regions for this Space ID */

        status =
            acpi_ev_install_space_handler(node, space_id, handler, setup,
                                          context);
        if (ACPI_FAILURE(status)) {
                goto unlock_and_exit;
        }

        /* Run all _REG methods for this address space */

        if (run_reg) {
                acpi_ev_execute_reg_methods(node, ACPI_UINT32_MAX, space_id,
                                            ACPI_REG_CONNECT);
        }

unlock_and_exit:
        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
        return_ACPI_STATUS(status);
}

acpi_status
acpi_install_address_space_handler(acpi_handle device,
                                   acpi_adr_space_type space_id,
                                   acpi_adr_space_handler handler,
                                   acpi_adr_space_setup setup, void *context)
{
        return acpi_install_address_space_handler_internal(device, space_id,
                                                           handler, setup,
                                                           context, TRUE);
}

ACPI_EXPORT_SYMBOL(acpi_install_address_space_handler)
acpi_status
acpi_install_address_space_handler_no_reg(acpi_handle device,
                                          acpi_adr_space_type space_id,
                                          acpi_adr_space_handler handler,
                                          acpi_adr_space_setup setup,
                                          void *context)
{
        return acpi_install_address_space_handler_internal(device, space_id,
                                                           handler, setup,
                                                           context, FALSE);
}

ACPI_EXPORT_SYMBOL(acpi_install_address_space_handler_no_reg)

/*******************************************************************************
 *
 * FUNCTION:    acpi_remove_address_space_handler
 *
 * PARAMETERS:  device          - Handle for the device
 *              space_id        - The address space ID
 *              handler         - Address of the handler
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Remove a previously installed handler.
 *
 ******************************************************************************/
acpi_status
acpi_remove_address_space_handler(acpi_handle device,
                                  acpi_adr_space_type space_id,
                                  acpi_adr_space_handler handler)
{
        union acpi_operand_object *obj_desc;
        union acpi_operand_object *handler_obj;
        union acpi_operand_object *region_obj;
        union acpi_operand_object **last_obj_ptr;
        struct acpi_namespace_node *node;
        acpi_status status;

        ACPI_FUNCTION_TRACE(acpi_remove_address_space_handler);

        /* Parameter validation */

        if (!device) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Convert and validate the device handle */

        node = acpi_ns_validate_handle(device);
        if (!node ||
            ((node->type != ACPI_TYPE_DEVICE) &&
             (node->type != ACPI_TYPE_PROCESSOR) &&
             (node->type != ACPI_TYPE_THERMAL) &&
             (node != acpi_gbl_root_node))) {
                status = AE_BAD_PARAMETER;
                goto unlock_and_exit;
        }

        /* Make sure the internal object exists */

        obj_desc = acpi_ns_get_attached_object(node);
        if (!obj_desc) {
                status = AE_NOT_EXIST;
                goto unlock_and_exit;
        }

        /* Find the address handler the user requested */

        handler_obj = obj_desc->common_notify.handler;
        last_obj_ptr = &obj_desc->common_notify.handler;
        while (handler_obj) {

                /* We have a handler, see if user requested this one */

                if (handler_obj->address_space.space_id == space_id) {

                        /* Handler must be the same as the installed handler */

                        if (handler_obj->address_space.handler != handler) {
                                status = AE_BAD_PARAMETER;
                                goto unlock_and_exit;
                        }

                        /* Matched space_id, first dereference this in the Regions */

                        ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
                                          "Removing address handler %p(%p) for region %s "
                                          "on Device %p(%p)\n",
                                          handler_obj, handler,
                                          acpi_ut_get_region_name(space_id),
                                          node, obj_desc));

                        region_obj = handler_obj->address_space.region_list;

                        /* Walk the handler's region list */

                        while (region_obj) {
                                /*
                                 * First disassociate the handler from the region.
                                 *
                                 * NOTE: this doesn't mean that the region goes away
                                 * The region is just inaccessible as indicated to
                                 * the _REG method
                                 */
                                acpi_ev_detach_region(region_obj, TRUE);

                                /*
                                 * Walk the list: Just grab the head because the
                                 * detach_region removed the previous head.
                                 */
                                region_obj =
                                    handler_obj->address_space.region_list;
                        }

                        /* Remove this Handler object from the list */

                        *last_obj_ptr = handler_obj->address_space.next;

                        /* Now we can delete the handler object */

                        acpi_ut_remove_reference(handler_obj);
                        goto unlock_and_exit;
                }

                /* Walk the linked list of handlers */

                last_obj_ptr = &handler_obj->address_space.next;
                handler_obj = handler_obj->address_space.next;
        }

        /* The handler does not exist */

        ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
                          "Unable to remove address handler %p for %s(%X), DevNode %p, obj %p\n",
                          handler, acpi_ut_get_region_name(space_id), space_id,
                          node, obj_desc));

        status = AE_NOT_EXIST;

unlock_and_exit:
        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
        return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_remove_address_space_handler)
/*******************************************************************************
 *
 * FUNCTION:    acpi_execute_reg_methods
 *
 * PARAMETERS:  device          - Handle for the device
 *              max_depth       - Depth to which search for _REG
 *              space_id        - The address space ID
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Execute _REG for all op_regions of a given space_id.
 *
 ******************************************************************************/
acpi_status
acpi_execute_reg_methods(acpi_handle device, u32 max_depth,
                         acpi_adr_space_type space_id)
{
        struct acpi_namespace_node *node;
        acpi_status status;

        ACPI_FUNCTION_TRACE(acpi_execute_reg_methods);

        /* Parameter validation */

        if (!device) {
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Convert and validate the device handle */

        node = acpi_ns_validate_handle(device);
        if (node) {

                /* Run all _REG methods for this address space */

                acpi_ev_execute_reg_methods(node, max_depth, space_id,
                                            ACPI_REG_CONNECT);
        } else {
                status = AE_BAD_PARAMETER;
        }

        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
        return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_execute_reg_methods)