acpi/acpinex/acpinex_event.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
 * Copyright (c) 2010, Intel Corporation.
 * All rights reserved.
 */

#include <sys/types.h>
#include <sys/atomic.h>
#include <sys/bitmap.h>
#include <sys/cmn_err.h>
#include <sys/note.h>
#include <sys/sunndi.h>
#include <sys/fastboot_impl.h>
#include <sys/sysevent.h>
#include <sys/sysevent/dr.h>
#include <sys/sysevent/eventdefs.h>
#include <sys/acpi/acpi.h>
#include <sys/acpica.h>
#include <sys/acpidev.h>
#include <sys/acpidev_dr.h>
#include <sys/acpinex.h>

int acpinex_event_support_remove = 0;

static volatile uint_t acpinex_dr_event_cnt = 0;
static ulong_t acpinex_object_type_mask[BT_BITOUL(ACPI_TYPE_NS_NODE_MAX + 1)];

/*
 * Generate DR_REQ event to syseventd.
 * Please refer to sys/sysevent/dr.h for message definition.
 */
static int
acpinex_event_generate_event(dev_info_t *dip, ACPI_HANDLE hdl, int req,
    int event, char *objname)
{
    int rv = 0;
    sysevent_id_t eid;
    sysevent_value_t evnt_val;
    sysevent_attr_list_t *evnt_attr_list = NULL;
    char *attach_pnt;
    char event_type[32];

    /* Add "attachment point" attribute. */
    attach_pnt = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
    if (ACPI_FAILURE(acpidev_dr_get_attachment_point(hdl,
        attach_pnt, MAXPATHLEN))) {
        cmn_err(CE_WARN,
            "!acpinex: failed to generate AP name for %s.", objname);
        kmem_free(attach_pnt, MAXPATHLEN);
        return (-1);
    }
    ASSERT(attach_pnt[0] != '\0');
    evnt_val.value_type = SE_DATA_TYPE_STRING;
    evnt_val.value.sv_string = attach_pnt;
    rv = sysevent_add_attr(&evnt_attr_list, DR_AP_ID, &evnt_val, KM_SLEEP);
    if (rv != 0) {
        cmn_err(CE_WARN,
            "!acpinex: failed to add attr [%s] for %s event.",
            DR_AP_ID, EC_DR);
        kmem_free(attach_pnt, MAXPATHLEN);
        return (rv);
    }

    /* Add "request type" attribute. */
    evnt_val.value_type = SE_DATA_TYPE_STRING;
    evnt_val.value.sv_string = SE_REQ2STR(req);
    rv = sysevent_add_attr(&evnt_attr_list, DR_REQ_TYPE, &evnt_val,
        KM_SLEEP);
    if (rv != 0) {
        cmn_err(CE_WARN,
            "!acpinex: failed to add attr [%s] for %s event.",
            DR_REQ_TYPE, EC_DR);
        sysevent_free_attr(evnt_attr_list);
        kmem_free(attach_pnt, MAXPATHLEN);
        return (rv);
    }

    /* Add "acpi-event-type" attribute. */
    switch (event) {
    case ACPI_NOTIFY_BUS_CHECK:
        (void) snprintf(event_type, sizeof (event_type),
            ACPIDEV_EVENT_TYPE_BUS_CHECK);
        break;
    case ACPI_NOTIFY_DEVICE_CHECK:
        (void) snprintf(event_type, sizeof (event_type),
            ACPIDEV_EVENT_TYPE_DEVICE_CHECK);
        break;
    case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
        (void) snprintf(event_type, sizeof (event_type),
            ACPIDEV_EVENT_TYPE_DEVICE_CHECK_LIGHT);
        break;
    case ACPI_NOTIFY_EJECT_REQUEST:
        (void) snprintf(event_type, sizeof (event_type),
            ACPIDEV_EVENT_TYPE_EJECT_REQUEST);
        break;
    default:
        cmn_err(CE_WARN,
            "!acpinex: unknown ACPI event type %d.", event);
        sysevent_free_attr(evnt_attr_list);
        kmem_free(attach_pnt, MAXPATHLEN);
        return (-1);
    }
    evnt_val.value_type = SE_DATA_TYPE_STRING;
    evnt_val.value.sv_string = event_type;
    rv = sysevent_add_attr(&evnt_attr_list, ACPIDEV_EVENT_TYPE_ATTR_NAME,
        &evnt_val, KM_SLEEP);
    if (rv != 0) {
        cmn_err(CE_WARN,
            "!acpinex: failed to add attr [%s] for %s event.",
            ACPIDEV_EVENT_TYPE_ATTR_NAME, EC_DR);
        sysevent_free_attr(evnt_attr_list);
        kmem_free(attach_pnt, MAXPATHLEN);
        return (rv);
    }

    rv = ddi_log_sysevent(dip, DDI_VENDOR_SUNW, EC_DR, ESC_DR_REQ,
        evnt_attr_list, &eid, KM_SLEEP);
    if (rv != DDI_SUCCESS) {
        cmn_err(CE_WARN,
            "!acpinex: failed to log DR_REQ event for %s.", objname);
        rv = -1;
    }

    nvlist_free(evnt_attr_list);
    kmem_free(attach_pnt, MAXPATHLEN);

    return (rv);
}

/*
 * Event handler for ACPI EJECT_REQUEST notifications.
 * EJECT_REQUEST notifications should be generated on the device to be ejected,
 * so no need to scan subtree of it.
 * It also invokes ACPI _OST method to update event status if call_ost is true.
 */
static void
acpinex_event_handle_eject_request(ACPI_HANDLE hdl, acpinex_softstate_t *sp,
    boolean_t call_ost)
{
    int code;
    char *objname;

    ASSERT(hdl != NULL);
    objname = acpidev_get_object_name(hdl);

    ASSERT(sp != NULL);
    ASSERT(sp->ans_dip != NULL && sp->ans_hdl != NULL);
    if (sp == NULL || sp->ans_dip == NULL || sp->ans_hdl == NULL) {
        if (call_ost) {
            (void) acpidev_eval_ost(hdl, ACPI_NOTIFY_EJECT_REQUEST,
                ACPI_OST_STA_FAILURE, NULL, 0);
        }
        ACPINEX_DEBUG(CE_WARN,
            "!acpinex: softstate data structure is invalid.");
        cmn_err(CE_WARN,
            "!acpinex: failed to handle EJECT_REQUEST event from %s.",
            objname);
        acpidev_free_object_name(objname);
        return;
    }

    if (acpinex_event_support_remove == 0) {
        cmn_err(CE_WARN,
            "!acpinex: hot-removing of device %s is unsupported.",
            objname);
        code = ACPI_OST_STA_EJECT_NOT_SUPPORT;
    } else if (acpinex_event_generate_event(sp->ans_dip, hdl,
        SE_OUTGOING_RES, ACPI_NOTIFY_EJECT_REQUEST, objname) != 0) {
        cmn_err(CE_WARN, "!acpinex: failed to generate ESC_DR_REQ "
            "event for device eject request from %s.", objname);
        code = ACPI_OST_STA_FAILURE;
    } else {
        cmn_err(CE_NOTE, "!acpinex: generate ESC_DR_REQ event for "
            "device eject request from %s.", objname);
        code = ACPI_OST_STA_EJECT_IN_PROGRESS;
    }
    if (call_ost) {
        (void) acpidev_eval_ost(hdl, ACPI_NOTIFY_EJECT_REQUEST,
            code, NULL, 0);
    }

    acpidev_free_object_name(objname);
}

struct acpinex_event_check_arg {
    acpinex_softstate_t *softstatep;
    int         event_type;
    uint32_t        device_insert;
    uint32_t        device_remove;
    uint32_t        device_fail;
};

static ACPI_STATUS
acpinex_event_handle_check_one(ACPI_HANDLE hdl, UINT32 lvl, void *ctx,
    void **retval)
{
    _NOTE(ARGUNUSED(lvl, retval));

    char *objname;
    int status, psta, csta;
    acpidev_data_handle_t dhdl;
    struct acpinex_event_check_arg *argp;

    ASSERT(hdl != NULL);
    ASSERT(ctx != NULL);
    argp = (struct acpinex_event_check_arg *)ctx;

    dhdl = acpidev_data_get_handle(hdl);
    if (dhdl == NULL) {
        /* Skip subtree if failed to get the data handle. */
        ACPINEX_DEBUG(CE_NOTE,
            "!acpinex: failed to get data associated with %p.", hdl);
        return (AE_CTRL_DEPTH);
    } else if (!acpidev_data_dr_capable(dhdl)) {
        return (AE_OK);
    }

    objname = acpidev_get_object_name(hdl);

    status = 0;
    /* Query previous device status. */
    psta = acpidev_data_get_status(dhdl);
    if (acpidev_check_device_enabled(psta)) {
        status |= 0x1;
    }
    /* Query current device status. */
    csta = acpidev_query_device_status(hdl);
    if (acpidev_check_device_enabled(csta)) {
        status |= 0x2;
    }

    switch (status) {
    case 0x0:
        /*FALLTHROUGH*/
    case 0x3:
        /* No status changes, keep on walking. */
        acpidev_free_object_name(objname);
        return (AE_OK);

    case 0x1:
        /* Surprising removal. */
        cmn_err(CE_WARN,
            "!acpinex: device %s has been surprisingly removed.",
            objname);
        if (argp->event_type == ACPI_NOTIFY_BUS_CHECK) {
            /*
             * According to ACPI spec, BUS_CHECK notification
             * should be triggered for hot-adding events only.
             */
            ACPINEX_DEBUG(CE_WARN,
                "!acpinex: device %s has been surprisingly removed "
                "when handling BUS_CHECK event.", objname);
        }
        acpidev_free_object_name(objname);
        argp->device_remove++;
        return (AE_CTRL_DEPTH);

    case 0x2:
        /* Hot-adding. */
        ACPINEX_DEBUG(CE_NOTE,
            "!acpinex: device %s has been inserted.", objname);
        argp->device_insert++;
        if (acpinex_event_generate_event(argp->softstatep->ans_dip, hdl,
            SE_INCOMING_RES, argp->event_type, objname) != 0) {
            cmn_err(CE_WARN,
                "!acpinex: failed to generate ESC_DR_REQ event for "
                "device insert request from %s.", objname);
            argp->device_fail++;
        } else {
            cmn_err(CE_NOTE, "!acpinex: generate ESC_DR_REQ event "
                "for device insert request from %s.", objname);
        }
        acpidev_free_object_name(objname);
        return (AE_OK);

    default:
        ASSERT(0);
        break;
    }

    return (AE_ERROR);
}

/*
 * Event handler for BUS_CHECK/DEVICE_CHECK/DEVICE_CHECK_LIGHT notifications.
 * These events may be signaled on parent/ancestor of devices to be hot-added,
 * so need to scan ACPI namespace to figure out devices in question.
 * It also invokes ACPI _OST method to update event status if call_ost is true.
 */
static void
acpinex_event_handle_check_request(int event, ACPI_HANDLE hdl,
    acpinex_softstate_t *sp, boolean_t call_ost)
{
    ACPI_STATUS rv;
    int code;
    char *objname;
    struct acpinex_event_check_arg arg;

    ASSERT(hdl != NULL);
    objname = acpidev_get_object_name(hdl);

    ASSERT(sp != NULL);
    ASSERT(sp->ans_dip != NULL && sp->ans_hdl != NULL);
    if (sp == NULL || sp->ans_dip == NULL || sp->ans_hdl == NULL) {
        if (call_ost) {
            (void) acpidev_eval_ost(hdl, event,
                ACPI_OST_STA_FAILURE, NULL, 0);
        }
        ACPINEX_DEBUG(CE_WARN,
            "!acpinex: softstate data structure is invalid.");
        cmn_err(CE_WARN, "!acpinex: failed to handle "
            "BUS/DEVICE_CHECK event from %s.", objname);
        acpidev_free_object_name(objname);
        return;
    }

    bzero(&arg, sizeof (arg));
    arg.event_type = event;
    arg.softstatep = sp;
    rv = acpinex_event_handle_check_one(hdl, 0, &arg, NULL);
    if (ACPI_SUCCESS(rv)) {
        rv = AcpiWalkNamespace(ACPI_TYPE_DEVICE, hdl,
            ACPIDEV_MAX_ENUM_LEVELS,
            &acpinex_event_handle_check_one, NULL, &arg, NULL);
    }

    if (ACPI_FAILURE(rv)) {
        /* Failed to scan the ACPI namespace. */
        cmn_err(CE_WARN, "!acpinex: failed to handle event %d from %s.",
            event, objname);
        code = ACPI_OST_STA_FAILURE;
    } else if (arg.device_remove != 0) {
        /* Surprising removal happened. */
        ACPINEX_DEBUG(CE_WARN,
            "!acpinex: some devices have been surprisingly removed.");
        code = ACPI_OST_STA_NOT_SUPPORT;
    } else if (arg.device_fail != 0) {
        /* Failed to handle some devices. */
        ACPINEX_DEBUG(CE_WARN,
            "!acpinex: failed to check status of some devices.");
        code = ACPI_OST_STA_FAILURE;
    } else if (arg.device_insert == 0) {
        /* No hot-added devices found. */
        cmn_err(CE_WARN,
            "!acpinex: no hot-added devices under %s found.", objname);
        code = ACPI_OST_STA_FAILURE;
    } else {
        code = ACPI_OST_STA_INSERT_IN_PROGRESS;
    }
    if (call_ost) {
        (void) acpidev_eval_ost(hdl, event, code, NULL, 0);
    }

    acpidev_free_object_name(objname);
}

static void
acpinex_event_system_handler(ACPI_HANDLE hdl, UINT32 type, void *arg)
{
    acpinex_softstate_t *sp;

    ASSERT(hdl != NULL);
    ASSERT(arg != NULL);
    sp = (acpinex_softstate_t *)arg;

    acpidev_dr_lock_all();
    mutex_enter(&sp->ans_lock);

    switch (type) {
    case ACPI_NOTIFY_BUS_CHECK:
        /*
         * Bus Check. This notification is performed on a device object
         * to indicate to OSPM that it needs to perform the Plug and
         * Play re-enumeration operation on the device tree starting
         * from the point where it has been notified. OSPM will only
         * perform this operation at boot, and when notified. It is
         * the responsibility of the ACPI AML code to notify OSPM at
         * any other times that this operation is required. The more
         * accurately and closer to the actual device tree change the
         * notification can be done, the more efficient the operating
         * system response will be; however, it can also be an issue
         * when a device change cannot be confirmed. For example, if
         * the hardware cannot notice a device change for a particular
         * location during a system sleeping state, it issues a Bus
         * Check notification on wake to inform OSPM that it needs to
         * check the configuration for a device change.
         */
        /*FALLTHROUGH*/
    case ACPI_NOTIFY_DEVICE_CHECK:
        /*
         * Device Check. Used to notify OSPM that the device either
         * appeared or disappeared. If the device has appeared, OSPM
         * will re-enumerate from the parent. If the device has
         * disappeared, OSPM will invalidate the state of the device.
         * OSPM may optimize out re-enumeration. If _DCK is present,
         * then Notify(object,1) is assumed to indicate an undock
         * request.
         */
        /*FALLTHROUGH*/
    case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
        /*
         * Device Check Light. Used to notify OSPM that the device
         * either appeared or disappeared. If the device has appeared,
         * OSPM will re-enumerate from the device itself, not the
         * parent. If the device has disappeared, OSPM will invalidate
         * the state of the device.
         */
        atomic_inc_uint(&acpinex_dr_event_cnt);
        acpinex_event_handle_check_request(type, hdl, sp, B_TRUE);
        break;

    case ACPI_NOTIFY_EJECT_REQUEST:
        /*
         * Eject Request. Used to notify OSPM that the device should
         * be ejected, and that OSPM needs to perform the Plug and Play
         * ejection operation. OSPM will run the _EJx method.
         */
        atomic_inc_uint(&acpinex_dr_event_cnt);
        acpinex_event_handle_eject_request(hdl, sp, B_TRUE);
        break;

    default:
        ACPINEX_DEBUG(CE_NOTE,
            "!acpinex: unhandled event(%d) on hdl %p under %s.",
            type, hdl, sp->ans_path);
        (void) acpidev_eval_ost(hdl, type, ACPI_OST_STA_NOT_SUPPORT,
            NULL, 0);
        break;
    }

    if (acpinex_dr_event_cnt != 0) {
        /*
         * Disable fast reboot if a CPU/MEM/IOH hotplug event happens.
         * Note: this is a temporary solution and will be revised when
         * fast reboot can support CPU/MEM/IOH DR operations in the
         * future.
         *
         * ACPI BIOS generates some static ACPI tables, such as MADT,
         * SRAT and SLIT, to describe the system hardware configuration
         * on power-on. When a CPU/MEM/IOH hotplug event happens, those
         * static tables won't be updated and will become stale.
         *
         * If we reset the system by fast reboot, BIOS will have no
         * chance to regenerate those staled static tables. Fast reboot
         * can't tolerate such inconsistency between staled ACPI tables
         * and real hardware configuration yet.
         *
         * A temporary solution is introduced to disable fast reboot if
         * CPU/MEM/IOH hotplug event happens. This solution should be
         * revised when fast reboot is enhanced to support CPU/MEM/IOH
         * DR operations.
         */
        fastreboot_disable(FBNS_HOTPLUG);
    }

    mutex_exit(&sp->ans_lock);
    acpidev_dr_unlock_all();
}

/*
 * Install event handler for ACPI system events.
 * Acpinex driver handles ACPI system events for its children,
 * device specific events will be handled by device drivers.
 * Return DDI_SUCCESS on success, and DDI_FAILURE on failure.
 */
static int
acpinex_event_install_handler(ACPI_HANDLE hdl, void *arg,
    ACPI_DEVICE_INFO *infop, acpidev_data_handle_t dhdl)
{
    ACPI_STATUS status;
    int rc = DDI_SUCCESS;

    ASSERT(hdl != NULL);
    ASSERT(dhdl != NULL);
    ASSERT(infop != NULL);

    /*
     * Check whether the event handler has already been installed on the
     * device object. With the introduction of ACPI Alias objects, which are
     * similar to symlinks in file systems, there may be multiple name
     * objects in the ACPI namespace pointing to the same underlying device
     * object. Those Alias objects need to be filtered out, otherwise
     * it will attempt to install the event handler multiple times on the
     * same device object which will fail.
     */
    if (acpidev_data_get_flag(dhdl, ACPIDEV_DATA_HANDLER_READY)) {
        return (DDI_SUCCESS);
    }
    status = AcpiInstallNotifyHandler(hdl, ACPI_SYSTEM_NOTIFY,
        acpinex_event_system_handler, arg);
    if (status == AE_OK || status == AE_ALREADY_EXISTS) {
        acpidev_data_set_flag(dhdl, ACPIDEV_DATA_HANDLER_READY);
    } else {
        char *objname;

        objname = acpidev_get_object_name(hdl);
        cmn_err(CE_WARN,
            "!acpinex: failed to install system event handler for %s.",
            objname);
        acpidev_free_object_name(objname);
        rc = DDI_FAILURE;
    }

    return (rc);
}

/*
 * Uninstall event handler for ACPI system events.
 * Return DDI_SUCCESS on success, and DDI_FAILURE on failure.
 */
static int
acpinex_event_uninstall_handler(ACPI_HANDLE hdl, ACPI_DEVICE_INFO *infop,
    acpidev_data_handle_t dhdl)
{
    ASSERT(hdl != NULL);
    ASSERT(dhdl != NULL);
    ASSERT(infop != NULL);

    if (!acpidev_data_get_flag(dhdl, ACPIDEV_DATA_HANDLER_READY)) {
        return (DDI_SUCCESS);
    }
    if (ACPI_SUCCESS(AcpiRemoveNotifyHandler(hdl, ACPI_SYSTEM_NOTIFY,
        acpinex_event_system_handler))) {
        acpidev_data_clear_flag(dhdl, ACPIDEV_DATA_HANDLER_READY);
    } else {
        char *objname;

        objname = acpidev_get_object_name(hdl);
        cmn_err(CE_WARN, "!acpinex: failed to uninstall system event "
            "handler for %s.", objname);
        acpidev_free_object_name(objname);
        return (DDI_FAILURE);
    }

    return (DDI_SUCCESS);
}

/*
 * Install/uninstall ACPI system event handler for child objects of hdl.
 * Return DDI_SUCCESS on success, and DDI_FAILURE on failure.
 */
static int
acpinex_event_walk(boolean_t init, acpinex_softstate_t *sp, ACPI_HANDLE hdl)
{
    int rc;
    int retval = DDI_SUCCESS;
    dev_info_t *dip;
    ACPI_HANDLE child = NULL;
    ACPI_OBJECT_TYPE type;
    ACPI_DEVICE_INFO *infop;
    acpidev_data_handle_t dhdl;

    /* Walk all child objects. */
    ASSERT(hdl != NULL);
    while (ACPI_SUCCESS(AcpiGetNextObject(ACPI_TYPE_ANY, hdl, child,
        &child))) {
        /* Skip unwanted object types. */
        if (ACPI_FAILURE(AcpiGetType(child, &type)) ||
            type > ACPI_TYPE_NS_NODE_MAX ||
            BT_TEST(acpinex_object_type_mask, type) == 0) {
            continue;
        }

        /* Get data associated with the object. Skip it if fails. */
        dhdl = acpidev_data_get_handle(child);
        if (dhdl == NULL) {
            ACPINEX_DEBUG(CE_NOTE, "!acpinex: failed to get data "
                "associated with %p, skip.", child);
            continue;
        }

        /* Query ACPI object info for the object. */
        if (ACPI_FAILURE(AcpiGetObjectInfo(child, &infop))) {
            cmn_err(CE_WARN,
                "!acpidnex: failed to get object info for %p.",
                child);
            continue;
        }

        if (init) {
            rc = acpinex_event_install_handler(child, sp, infop,
                dhdl);
            if (rc != DDI_SUCCESS) {
                ACPINEX_DEBUG(CE_WARN, "!acpinex: failed to "
                    "install handler for child %p of %s.",
                    child, sp->ans_path);
                retval = DDI_FAILURE;
            /*
             * Try to handle descendants if both of the
             * following two conditions are true:
             * 1) Device corresponding to the current object is
             *    enabled. If the device is absent/disabled,
             *    no notification should be generated from
             *    descendant objects of it.
             * 2) No Solaris device node has been created for the
             *    current object yet. If the device node has been
             *    created for the current object, notification
             *    events from child objects should be handled by
             *    the corresponding driver.
             */
            } else if (acpidev_check_device_enabled(
                acpidev_data_get_status(dhdl)) &&
                ACPI_FAILURE(acpica_get_devinfo(child, &dip))) {
                rc = acpinex_event_walk(B_TRUE, sp, child);
                if (rc != DDI_SUCCESS) {
                    ACPINEX_DEBUG(CE_WARN,
                        "!acpinex: failed to install "
                        "handler for descendants of %s.",
                        sp->ans_path);
                    retval = DDI_FAILURE;
                }
            }
        } else {
            rc = DDI_SUCCESS;
            /* Uninstall handler for descendants if needed. */
            if (ACPI_FAILURE(acpica_get_devinfo(child, &dip))) {
                rc = acpinex_event_walk(B_FALSE, sp, child);
            }
            if (rc == DDI_SUCCESS) {
                rc = acpinex_event_uninstall_handler(child,
                    infop, dhdl);
            }
            /* Undo will be done by caller in case of failure. */
            if (rc != DDI_SUCCESS) {
                ACPINEX_DEBUG(CE_WARN, "!acpinex: failed to "
                    "uninstall handler for descendants of %s.",
                    sp->ans_path);
                AcpiOsFree(infop);
                retval = DDI_FAILURE;
                break;
            }
        }

        /* Release cached resources. */
        AcpiOsFree(infop);
    }

    return (retval);
}

int
acpinex_event_scan(acpinex_softstate_t *sp, boolean_t init)
{
    int rc;

    ASSERT(sp != NULL);
    ASSERT(sp->ans_hdl != NULL);
    ASSERT(sp->ans_dip != NULL);
    if (sp == NULL || sp->ans_hdl == NULL || sp->ans_dip == NULL) {
        ACPINEX_DEBUG(CE_WARN,
            "!acpinex: invalid parameter to acpinex_event_scan().");
        return (DDI_FAILURE);
    }

    /* Lock current device node and walk all child device nodes of it. */
    mutex_enter(&sp->ans_lock);

    rc = acpinex_event_walk(init, sp, sp->ans_hdl);
    if (rc != DDI_SUCCESS) {
        if (init) {
            ACPINEX_DEBUG(CE_WARN, "!acpinex: failed to "
                "configure child objects of %s.", sp->ans_path);
            rc = DDI_FAILURE;
        } else {
            ACPINEX_DEBUG(CE_WARN, "!acpinex: failed to "
                "unconfigure child objects of %s.", sp->ans_path);
            /* Undo in case of errors */
            (void) acpinex_event_walk(B_TRUE, sp, sp->ans_hdl);
            rc = DDI_FAILURE;
        }
    }

    mutex_exit(&sp->ans_lock);

    return (rc);
}

void
acpinex_event_init(void)
{
    /*
     * According to ACPI specifications, notification is only supported on
     * Device, Processor and ThermalZone. Currently we only need to handle
     * Device and Processor objects.
     */
    BT_SET(acpinex_object_type_mask, ACPI_TYPE_PROCESSOR);
    BT_SET(acpinex_object_type_mask, ACPI_TYPE_DEVICE);
}

void
acpinex_event_fini(void)
{
    bzero(acpinex_object_type_mask, sizeof (acpinex_object_type_mask));
}