evxfevnt.c

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/******************************************************************************
 *
 * Module Name: evxfevnt - External Interfaces, ACPI event disable/enable
 *
 *****************************************************************************/

/*
 * 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 "actables.h"

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evxfevnt")

#if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
/*******************************************************************************
 *
 * FUNCTION:    acpi_enable
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Transfers the system into ACPI mode.
 *
 ******************************************************************************/

acpi_status acpi_enable(void)
{
    acpi_status status;
    int retry;

    ACPI_FUNCTION_TRACE(acpi_enable);

    /* ACPI tables must be present */

    if (!acpi_tb_tables_loaded()) {
        return_ACPI_STATUS(AE_NO_ACPI_TABLES);
    }

    /* Check current mode */

    if (acpi_hw_get_mode() == ACPI_SYS_MODE_ACPI) {
        ACPI_DEBUG_PRINT((ACPI_DB_INIT,
                  "System is already in ACPI mode\n"));
        return_ACPI_STATUS(AE_OK);
    }

    /* Transition to ACPI mode */

    status = acpi_hw_set_mode(ACPI_SYS_MODE_ACPI);
    if (ACPI_FAILURE(status)) {
        ACPI_ERROR((AE_INFO,
                "Could not transition to ACPI mode"));
        return_ACPI_STATUS(status);
    }

    /* Sanity check that transition succeeded */

    for (retry = 0; retry < 30000; ++retry) {
        if (acpi_hw_get_mode() == ACPI_SYS_MODE_ACPI) {
            if (retry != 0)
                ACPI_WARNING((AE_INFO,
                "Platform took > %d00 usec to enter ACPI mode", retry));
            return_ACPI_STATUS(AE_OK);
        }
        acpi_os_stall(100); /* 100 usec */
    }

    ACPI_ERROR((AE_INFO, "Hardware did not enter ACPI mode"));
    return_ACPI_STATUS(AE_NO_HARDWARE_RESPONSE);
}

ACPI_EXPORT_SYMBOL(acpi_enable)

/*******************************************************************************
 *
 * FUNCTION:    acpi_disable
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Transfers the system into LEGACY (non-ACPI) mode.
 *
 ******************************************************************************/
acpi_status acpi_disable(void)
{
    acpi_status status = AE_OK;

    ACPI_FUNCTION_TRACE(acpi_disable);

    if (acpi_hw_get_mode() == ACPI_SYS_MODE_LEGACY) {
        ACPI_DEBUG_PRINT((ACPI_DB_INIT,
                  "System is already in legacy (non-ACPI) mode\n"));
    } else {
        /* Transition to LEGACY mode */

        status = acpi_hw_set_mode(ACPI_SYS_MODE_LEGACY);

        if (ACPI_FAILURE(status)) {
            ACPI_ERROR((AE_INFO,
                    "Could not exit ACPI mode to legacy mode"));
            return_ACPI_STATUS(status);
        }

        ACPI_DEBUG_PRINT((ACPI_DB_INIT, "ACPI mode disabled\n"));
    }

    return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_disable)

/*******************************************************************************
 *
 * FUNCTION:    acpi_enable_event
 *
 * PARAMETERS:  event           - The fixed eventto be enabled
 *              flags           - Reserved
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Enable an ACPI event (fixed)
 *
 ******************************************************************************/
acpi_status acpi_enable_event(u32 event, u32 flags)
{
    acpi_status status = AE_OK;
    u32 value;

    ACPI_FUNCTION_TRACE(acpi_enable_event);

    /* Decode the Fixed Event */

    if (event > ACPI_EVENT_MAX) {
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    /*
     * Enable the requested fixed event (by writing a one to the enable
     * register bit)
     */
    status =
        acpi_write_bit_register(acpi_gbl_fixed_event_info[event].
                    enable_register_id, ACPI_ENABLE_EVENT);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* Make sure that the hardware responded */

    status =
        acpi_read_bit_register(acpi_gbl_fixed_event_info[event].
                   enable_register_id, &value);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    if (value != 1) {
        ACPI_ERROR((AE_INFO,
                "Could not enable %s event",
                acpi_ut_get_event_name(event)));
        return_ACPI_STATUS(AE_NO_HARDWARE_RESPONSE);
    }

    return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_enable_event)

/*******************************************************************************
 *
 * FUNCTION:    acpi_disable_event
 *
 * PARAMETERS:  Event           - The fixed eventto be enabled
 *              Flags           - Reserved
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Disable an ACPI event (fixed)
 *
 ******************************************************************************/
acpi_status acpi_disable_event(u32 event, u32 flags)
{
    acpi_status status = AE_OK;
    u32 value;

    ACPI_FUNCTION_TRACE(acpi_disable_event);

    /* Decode the Fixed Event */

    if (event > ACPI_EVENT_MAX) {
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    /*
     * Disable the requested fixed event (by writing a zero to the enable
     * register bit)
     */
    status =
        acpi_write_bit_register(acpi_gbl_fixed_event_info[event].
                    enable_register_id, ACPI_DISABLE_EVENT);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    status =
        acpi_read_bit_register(acpi_gbl_fixed_event_info[event].
                   enable_register_id, &value);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    if (value != 0) {
        ACPI_ERROR((AE_INFO,
                "Could not disable %s events",
                acpi_ut_get_event_name(event)));
        return_ACPI_STATUS(AE_NO_HARDWARE_RESPONSE);
    }

    return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_disable_event)

/*******************************************************************************
 *
 * FUNCTION:    acpi_clear_event
 *
 * PARAMETERS:  event           - The fixed event to be cleared
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Clear an ACPI event (fixed)
 *
 ******************************************************************************/
acpi_status acpi_clear_event(u32 event)
{
    acpi_status status = AE_OK;

    ACPI_FUNCTION_TRACE(acpi_clear_event);

    /* Decode the Fixed Event */

    if (event > ACPI_EVENT_MAX) {
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    /*
     * Clear the requested fixed event (By writing a one to the status
     * register bit)
     */
    status =
        acpi_write_bit_register(acpi_gbl_fixed_event_info[event].
                    status_register_id, ACPI_CLEAR_STATUS);

    return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_clear_event)

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_event_status
 *
 * PARAMETERS:  event           - The fixed event
 *              event_status    - Where the current status of the event will
 *                                be returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Obtains and returns the current status of the event
 *
 ******************************************************************************/
acpi_status acpi_get_event_status(u32 event, acpi_event_status * event_status)
{
    acpi_status status = AE_OK;
    u32 value;

    ACPI_FUNCTION_TRACE(acpi_get_event_status);

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

    /* Decode the Fixed Event */

    if (event > ACPI_EVENT_MAX) {
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    /* Get the status of the requested fixed event */

    status =
        acpi_read_bit_register(acpi_gbl_fixed_event_info[event].
                  enable_register_id, &value);
    if (ACPI_FAILURE(status))
        return_ACPI_STATUS(status);

    *event_status = value;

    status =
        acpi_read_bit_register(acpi_gbl_fixed_event_info[event].
                  status_register_id, &value);
    if (ACPI_FAILURE(status))
        return_ACPI_STATUS(status);

    if (value)
        *event_status |= ACPI_EVENT_FLAG_SET;

    if (acpi_gbl_fixed_event_handlers[event].handler)
        *event_status |= ACPI_EVENT_FLAG_HANDLE;

    return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_get_event_status)
#endif              /* !ACPI_REDUCED_HARDWARE */