evxfregn.c

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/******************************************************************************
 *
 * Module Name: evxfregn - External Interfaces, ACPI Operation Regions and
 *                         Address Spaces.
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2012, 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 <linux/export.h>
#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
 *
 * 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
 *
 * 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.)
 *
 ******************************************************************************/
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)
{
    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;
    }

    /*
     * For the default space_IDs, (the IDs for which there are default region handlers
     * installed) Only execute the _REG methods if the global initialization _REG
     * methods have already been run (via acpi_initialize_objects). In other words,
     * we will defer the execution of the _REG methods for these space_IDs until
     * execution of acpi_initialize_objects. This is done because we need the handlers
     * for the default spaces (mem/io/pci/table) to be installed before we can run
     * any control methods (or _REG methods). There is known BIOS code that depends
     * on this.
     *
     * For all other space_IDs, we can safely execute the _REG methods immediately.
     * This means that for IDs like embedded_controller, this function should be called
     * only after acpi_enable_subsystem has been called.
     */
    switch (space_id) {
    case ACPI_ADR_SPACE_SYSTEM_MEMORY:
    case ACPI_ADR_SPACE_SYSTEM_IO:
    case ACPI_ADR_SPACE_PCI_CONFIG:
    case ACPI_ADR_SPACE_DATA_TABLE:

        if (!acpi_gbl_reg_methods_executed) {

            /* We will defer execution of the _REG methods for this space */
            goto unlock_and_exit;
        }
        break;

    default:
        break;
    }

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

    status = acpi_ev_execute_reg_methods(node, space_id);

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

ACPI_EXPORT_SYMBOL(acpi_install_address_space_handler)

/*******************************************************************************
 *
 * 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->device.handler;
    last_obj_ptr = &obj_desc->device.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)