Expand PMF_FN_* macros.

[netbsd-mini2440.git] / sys / dev / sysmon / sysmon_envsys_events.c

/* $NetBSD: sysmon_envsys_events.c,v 1.73 2010/01/01 15:41:25 pgoyette Exp $ */

/*-
 * Copyright (c) 2007, 2008 Juan Romero Pardines.
 * 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.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, 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 DAMAGE.
 */

/*
 * sysmon_envsys(9) events framework.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: sysmon_envsys_events.c,v 1.73 2010/01/01 15:41:25 pgoyette Exp $");

#include <sys/param.h>
#include <sys/types.h>
#include <sys/conf.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/mutex.h>
#include <sys/kmem.h>
#include <sys/callout.h>

/* #define ENVSYS_DEBUG */

#include <dev/sysmon/sysmonvar.h>
#include <dev/sysmon/sysmon_envsysvar.h>

struct sme_sensor_event {
        int             state;
        int             event;
};

static const struct sme_sensor_event sme_sensor_event[] = {
        { ENVSYS_SVALID,                        PENVSYS_EVENT_NORMAL },
        { ENVSYS_SCRITOVER,                     PENVSYS_EVENT_CRITOVER },
        { ENVSYS_SCRITUNDER,                    PENVSYS_EVENT_CRITUNDER },
        { ENVSYS_SWARNOVER,                     PENVSYS_EVENT_WARNOVER },
        { ENVSYS_SWARNUNDER,                    PENVSYS_EVENT_WARNUNDER },
        { ENVSYS_BATTERY_CAPACITY_NORMAL,       PENVSYS_EVENT_NORMAL },
        { ENVSYS_BATTERY_CAPACITY_WARNING,      PENVSYS_EVENT_BATT_WARN },
        { ENVSYS_BATTERY_CAPACITY_CRITICAL,     PENVSYS_EVENT_BATT_CRIT },
        { -1,                                   -1 }
};

static bool sysmon_low_power;

#define SME_EVTIMO      (SME_EVENTS_DEFTIMEOUT * hz)

static bool sme_event_check_low_power(void);
static bool sme_battery_check(void);
static bool sme_battery_critical(envsys_data_t *);
static bool sme_acadapter_check(void);

/*
 * sme_event_register:
 *
 *      + Registers a new sysmon envsys event or updates any event
 *        already in the queue.
 */
int
sme_event_register(prop_dictionary_t sdict, envsys_data_t *edata,
                   struct sysmon_envsys *sme, sysmon_envsys_lim_t *lims,
                   int crittype, int powertype)
{
        sme_event_t *see = NULL, *osee = NULL;
        prop_object_t obj;
        int error = 0;
        const char *objkey;

        KASSERT(sdict != NULL || edata != NULL || sme != NULL);

        /* 
         * check if the event is already on the list and return
         * EEXIST if value provided hasn't been changed.
         */
        mutex_enter(&sme->sme_mtx);
        LIST_FOREACH(osee, &sme->sme_events_list, see_list) {
                if (strcmp(edata->desc, osee->see_pes.pes_sensname) != 0)
                        continue;
                if (crittype != osee->see_type)
                        continue;

                DPRINTF(("%s: dev %s sensor %s lim_flags 0x%04x event exists\n",
                    __func__, sme->sme_name, edata->desc, lims->sel_flags));

                see = osee;
                if (lims->sel_flags & PROP_CRITMAX) {
                        if (lims->sel_critmax == see->see_lims.sel_critmax) {
                                DPRINTF(("%s: type=%d (critmax exists)\n",
                                    __func__, crittype));
                                error = EEXIST;
                                lims->sel_flags &= ~PROP_CRITMAX;
                        }
                }
                if (lims->sel_flags & PROP_WARNMAX) {
                        if (lims->sel_warnmax == see->see_lims.sel_warnmax) {
                                DPRINTF(("%s: type=%d (warnmax exists)\n",
                                    __func__, crittype));
                                error = EEXIST;
                                lims->sel_flags &= ~PROP_WARNMAX;
                        }
                }
                if (lims->sel_flags & (PROP_WARNMIN | PROP_BATTWARN)) {
                        if (lims->sel_warnmin == see->see_lims.sel_warnmin) {
                                DPRINTF(("%s: type=%d (warnmin exists)\n",
                                    __func__, crittype));
                                error = EEXIST;
                                lims->sel_flags &= ~(PROP_WARNMIN | PROP_BATTWARN);
                        }
                }
                if (lims->sel_flags & (PROP_CRITMIN | PROP_BATTCAP)) {
                        if (lims->sel_critmin == see->see_lims.sel_critmin) {
                                DPRINTF(("%s: type=%d (critmin exists)\n",
                                    __func__, crittype));
                                error = EEXIST;
                                lims->sel_flags &= ~(PROP_CRITMIN | PROP_BATTCAP);
                        }
                }
                break;
        }
        if (see == NULL) {
                /*
                 * New event requested - allocate a sysmon_envsys event.
                 */
                see = kmem_zalloc(sizeof(*see), KM_SLEEP);
                if (see == NULL)
                        return ENOMEM;

                DPRINTF(("%s: dev %s sensor %s lim_flags 0x%04x new event\n",
                    __func__, sme->sme_name, edata->desc, lims->sel_flags));

                see->see_type = crittype;
                see->see_sme = sme;
                see->see_edata = edata;

                /* Initialize sensor type and previously-sent state */

                see->see_pes.pes_type = powertype;

                switch (crittype) {
                case PENVSYS_EVENT_LIMITS:
                        see->see_evsent = ENVSYS_SVALID;
                        break;
                case PENVSYS_EVENT_CAPACITY:
                        see->see_evsent = ENVSYS_BATTERY_CAPACITY_NORMAL;
                        break;
                case PENVSYS_EVENT_STATE_CHANGED:
                        if (edata->units == ENVSYS_BATTERY_CAPACITY)
                                see->see_evsent = ENVSYS_BATTERY_CAPACITY_NORMAL;
                        else if (edata->units == ENVSYS_DRIVE)
                                see->see_evsent = ENVSYS_DRIVE_EMPTY;
                        else
                                panic("%s: bad units for "
                                      "PENVSYS_EVENT_STATE_CHANGED", __func__);
                        break;
                case PENVSYS_EVENT_CRITICAL:
                default:
                        see->see_evsent = 0;
                        break;
                }

                (void)strlcpy(see->see_pes.pes_dvname, sme->sme_name,
                    sizeof(see->see_pes.pes_dvname));
                (void)strlcpy(see->see_pes.pes_sensname, edata->desc,
                    sizeof(see->see_pes.pes_sensname));
        }

        /*
         * Limit operation requested.
         */
        if (lims->sel_flags & PROP_CRITMAX) {
                objkey = "critical-max";
                obj = prop_dictionary_get(sdict, objkey);
                if (obj && prop_object_type(obj) != PROP_TYPE_NUMBER) {
                        DPRINTF(("%s: (%s) %s object not TYPE_NUMBER\n",
                            __func__, sme->sme_name, objkey));
                        error = ENOTSUP;
                } else {
                        see->see_lims.sel_critmax = lims->sel_critmax;
                        error = sme_sensor_upint32(sdict, objkey,
                                                   lims->sel_critmax);
                        DPRINTF(("%s: (%s) event [sensor=%s type=%d] "
                            "(%s updated)\n", __func__, sme->sme_name,
                            edata->desc, crittype, objkey));
                }
                if (error && error != EEXIST)
                        goto out;
                see->see_edata->upropset |= PROP_CRITMAX;
                see->see_lims.sel_flags |= PROP_CRITMAX;
        }

        if (lims->sel_flags & PROP_WARNMAX) {
                objkey = "warning-max";
                obj = prop_dictionary_get(sdict, objkey);
                if (obj && prop_object_type(obj) != PROP_TYPE_NUMBER) {
                        DPRINTF(("%s: (%s) %s object not TYPE_NUMBER\n",
                            __func__, sme->sme_name, objkey));
                        error = ENOTSUP;
                } else {
                        see->see_lims.sel_warnmax = lims->sel_warnmax;
                        error = sme_sensor_upint32(sdict, objkey,
                                                   lims->sel_warnmax);
                        DPRINTF(("%s: (%s) event [sensor=%s type=%d] "
                            "(%s updated)\n", __func__, sme->sme_name,
                            edata->desc, crittype, objkey));
                }
                if (error && error != EEXIST)
                        goto out;
                see->see_edata->upropset |= PROP_WARNMAX;
                see->see_lims.sel_flags |= PROP_WARNMAX;
        }

        if (lims->sel_flags & PROP_WARNMIN) {
                objkey = "warning-min";
                obj = prop_dictionary_get(sdict, objkey);
                if (obj && prop_object_type(obj) != PROP_TYPE_NUMBER) {
                        DPRINTF(("%s: (%s) %s object not TYPE_NUMBER\n",
                            __func__, sme->sme_name, objkey));
                        error = ENOTSUP;
                } else {
                        see->see_lims.sel_warnmin = lims->sel_warnmin;
                        error = sme_sensor_upint32(sdict, objkey,
                                                   lims->sel_warnmin);
                        DPRINTF(("%s: (%s) event [sensor=%s type=%d] "
                            "(%s updated)\n", __func__, sme->sme_name,
                            edata->desc, crittype, objkey));
                }
                if (error && error != EEXIST)
                        goto out;
                see->see_edata->upropset |= PROP_WARNMIN;
                see->see_lims.sel_flags |= PROP_WARNMIN;
        }

        if (lims->sel_flags & PROP_CRITMIN) {
                objkey = "critical-min";
                obj = prop_dictionary_get(sdict, objkey);
                if (obj && prop_object_type(obj) != PROP_TYPE_NUMBER) {
                        DPRINTF(("%s: (%s) %s object not TYPE_NUMBER\n",
                            __func__, sme->sme_name, objkey));
                        error = ENOTSUP;
                } else {
                        see->see_lims.sel_critmin = lims->sel_critmin;
                        error = sme_sensor_upint32(sdict, objkey,
                                                   lims->sel_critmin);
                        DPRINTF(("%s: (%s) event [sensor=%s type=%d] "
                            "(%s updated)\n", __func__, sme->sme_name,
                            edata->desc, crittype, objkey));
                }
                if (error && error != EEXIST)
                        goto out;
                see->see_edata->upropset |= PROP_CRITMIN;
                see->see_lims.sel_flags |= PROP_CRITMIN;
        }

        if (lims->sel_flags & PROP_BATTWARN) {
                objkey = "warning-capacity";
                obj = prop_dictionary_get(sdict, objkey);
                if (obj && prop_object_type(obj) != PROP_TYPE_NUMBER) {
                        DPRINTF(("%s: (%s) %s object not TYPE_NUMBER\n",
                            __func__, sme->sme_name, objkey));
                        error = ENOTSUP;
                } else {
                        see->see_lims.sel_warnmin = lims->sel_warnmin;
                        error = sme_sensor_upint32(sdict, objkey,
                                                   lims->sel_warnmin);
                        DPRINTF(("%s: (%s) event [sensor=%s type=%d] "
                            "(%s updated)\n", __func__, sme->sme_name,
                            edata->desc, crittype, objkey));
                }
                if (error && error != EEXIST)
                        goto out;
                see->see_edata->upropset |= PROP_BATTWARN;
                see->see_lims.sel_flags |= PROP_BATTWARN;
        }

        if (lims->sel_flags & PROP_BATTCAP) {
                objkey = "critical-capacity";
                obj = prop_dictionary_get(sdict, objkey);
                if (obj && prop_object_type(obj) != PROP_TYPE_NUMBER) {
                        DPRINTF(("%s: (%s) %s object not TYPE_NUMBER\n",
                            __func__, sme->sme_name, objkey));
                        error = ENOTSUP;
                } else {
                        see->see_lims.sel_critmin = lims->sel_critmin;
                        error = sme_sensor_upint32(sdict, objkey,
                                                   lims->sel_critmin);
                        DPRINTF(("%s: (%s) event [sensor=%s type=%d] "
                            "(%s updated)\n", __func__, sme->sme_name,
                            edata->desc, crittype, objkey));
                }
                if (error && error != EEXIST)
                        goto out;
                see->see_edata->upropset |= PROP_BATTCAP;
                see->see_lims.sel_flags |= PROP_BATTCAP;
        }

        if (lims->sel_flags & PROP_DRIVER_LIMITS)
                see->see_lims.sel_flags |= PROP_DRIVER_LIMITS;

        DPRINTF(("%s: (%s) event registered (sensor=%s snum=%d type=%d "
            "critmin=%" PRIu32 " warnmin=%" PRIu32 " warnmax=%" PRIu32
            " critmax=%" PRIu32 " props 0x%04x)\n", __func__,
            see->see_sme->sme_name, see->see_pes.pes_sensname,
            see->see_edata->sensor, see->see_type, see->see_lims.sel_critmin,
            see->see_lims.sel_warnmin, see->see_lims.sel_warnmax,
            see->see_lims.sel_critmax, see->see_edata->upropset));
        /*
         * Initialize the events framework if it wasn't initialized before.
         */
        if ((sme->sme_flags & SME_CALLOUT_INITIALIZED) == 0)
                error = sme_events_init(sme);

        /*
         * If driver requested notification, advise it of new
         * limit values
         */
        if (sme->sme_set_limits) {
                see->see_lims.sel_flags = see->see_edata->upropset &
                                          PROP_LIMITS;
                (*sme->sme_set_limits)(sme, edata, &(see->see_lims));
        }

out:
        if ((error == 0 || error == EEXIST) && osee == NULL)
                LIST_INSERT_HEAD(&sme->sme_events_list, see, see_list);

        mutex_exit(&sme->sme_mtx);

        return error;
}

/*
 * sme_event_unregister_all:
 *
 *      + Unregisters all events associated with a sysmon envsys device.
 */
void
sme_event_unregister_all(struct sysmon_envsys *sme)
{
        sme_event_t *see;
        int evcounter = 0;

        KASSERT(sme != NULL);

        mutex_enter(&sme->sme_mtx);
        LIST_FOREACH(see, &sme->sme_events_list, see_list) {
                while (see->see_flags & SEE_EVENT_WORKING)
                        cv_wait(&sme->sme_condvar, &sme->sme_mtx);

                if (strcmp(see->see_pes.pes_dvname, sme->sme_name) == 0)
                        evcounter++;
        }

        DPRINTF(("%s: total events %d (%s)\n", __func__,
            evcounter, sme->sme_name));

        while ((see = LIST_FIRST(&sme->sme_events_list))) {
                if (evcounter == 0)
                        break;

                if (strcmp(see->see_pes.pes_dvname, sme->sme_name) == 0) {
                        LIST_REMOVE(see, see_list);
                        DPRINTF(("%s: event %s %d removed (%s)\n", __func__,
                            see->see_pes.pes_sensname, see->see_type,
                            sme->sme_name));
                        kmem_free(see, sizeof(*see));
                        evcounter--;
                }
        }

        if (LIST_EMPTY(&sme->sme_events_list))
                if (sme->sme_flags & SME_CALLOUT_INITIALIZED)
                        sme_events_destroy(sme);
        mutex_exit(&sme->sme_mtx);
}

/*
 * sme_event_unregister:
 *
 *      + Unregisters an event from the specified sysmon envsys device.
 */
int
sme_event_unregister(struct sysmon_envsys *sme, const char *sensor, int type)
{
        sme_event_t *see;
        bool found = false;

        KASSERT(sensor != NULL);

        mutex_enter(&sme->sme_mtx);
        LIST_FOREACH(see, &sme->sme_events_list, see_list) {
                if (strcmp(see->see_pes.pes_sensname, sensor) == 0) {
                        if (see->see_type == type) {
                                found = true;
                                break;
                        }
                }
        }

        if (!found) {
                mutex_exit(&sme->sme_mtx);
                return EINVAL;
        }

        /*
         * Wait for the event to finish its work, remove from the list
         * and release resouces.
         */
        while (see->see_flags & SEE_EVENT_WORKING)
                cv_wait(&sme->sme_condvar, &sme->sme_mtx);

        DPRINTF(("%s: removed dev=%s sensor=%s type=%d\n",
            __func__, see->see_pes.pes_dvname, sensor, type));
        LIST_REMOVE(see, see_list);
        /*
         * So the events list is empty, we'll do the following:
         *
         *      - stop and destroy the callout.
         *      - destroy the workqueue.
         */
        if (LIST_EMPTY(&sme->sme_events_list))
                sme_events_destroy(sme);
        mutex_exit(&sme->sme_mtx);

        kmem_free(see, sizeof(*see));
        return 0;
}

/*
 * sme_event_drvadd:
 *
 *      + Registers a new event for a device that had enabled any of
 *        the monitoring flags in the driver.
 */
void
sme_event_drvadd(void *arg)
{
        sme_event_drv_t *sed_t = arg;
        sysmon_envsys_lim_t lims;
        int error = 0;

        KASSERT(sed_t != NULL);

#define SEE_REGEVENT(a, b, c)                                           \
do {                                                                    \
        if (sed_t->sed_edata->flags & (a)) {                            \
                char str[ENVSYS_DESCLEN] = "monitoring-state-";         \
                                                                        \
                error = sme_event_register(sed_t->sed_sdict,            \
                                      sed_t->sed_edata,                 \
                                      sed_t->sed_sme,                   \
                                      &lims,                            \
                                      (b),                              \
                                      sed_t->sed_powertype);            \
                if (error && error != EEXIST)                           \
                        printf("%s: failed to add event! "              \
                            "error=%d sensor=%s event=%s\n",            \
                            __func__, error,                            \
                            sed_t->sed_edata->desc, (c));               \
                else {                                                  \
                        (void)strlcat(str, (c), sizeof(str));           \
                        prop_dictionary_set_bool(sed_t->sed_sdict,      \
                                                 str,                   \
                                                 true);                 \
                }                                                       \
        }                                                               \
} while (/* CONSTCOND */ 0)

        /*
         * If driver provides a method to retrieve its internal limit
         * values, call it and use those returned values as initial
         * limits for event monitoring.
         */
        lims.sel_flags = 0;
        if (sed_t->sed_edata->flags & ENVSYS_FMONLIMITS)
                if (sed_t->sed_sme->sme_get_limits)
                        (*sed_t->sed_sme->sme_get_limits)(sed_t->sed_sme,
                                                          sed_t->sed_edata,
                                                          &lims);
        /*
         * If no values returned, don't create the event monitor at
         * this time.  We'll get another chance later when the user
         * provides us with limits.
         */
        if (lims.sel_flags == 0)
                sed_t->sed_edata->flags &= ~ENVSYS_FMONLIMITS;

        /*
         * If driver doesn't provide a way to "absorb" user-specified
         * limit values, we must monitor all limits ourselves
         */
        else if (sed_t->sed_sme->sme_set_limits == NULL)
                lims.sel_flags &= ~PROP_DRIVER_LIMITS;

        /* Register the events that were specified */

        SEE_REGEVENT(ENVSYS_FMONCRITICAL,
                     PENVSYS_EVENT_CRITICAL,
                     "critical");

        SEE_REGEVENT(ENVSYS_FMONSTCHANGED,
                     PENVSYS_EVENT_STATE_CHANGED,
                     "state-changed");

        SEE_REGEVENT(ENVSYS_FMONLIMITS,
                     PENVSYS_EVENT_LIMITS,
                     "hw-range-limits");

        /* 
         * we are done, free memory now.
         */
        kmem_free(sed_t, sizeof(*sed_t));
}

/*
 * sme_events_init:
 *
 *      + Initialize the events framework for this device.
 */
int
sme_events_init(struct sysmon_envsys *sme)
{
        int error = 0;
        uint64_t timo;

        KASSERT(sme != NULL);
        KASSERT(mutex_owned(&sme->sme_mtx));

        if (sme->sme_events_timeout)
                timo = sme->sme_events_timeout * hz;
        else
                timo = SME_EVTIMO;

        error = workqueue_create(&sme->sme_wq, sme->sme_name,
            sme_events_worker, sme, PRI_NONE, IPL_SOFTCLOCK, WQ_MPSAFE);
        if (error)
                return error;

        mutex_init(&sme->sme_callout_mtx, MUTEX_DEFAULT, IPL_SOFTCLOCK);
        callout_init(&sme->sme_callout, CALLOUT_MPSAFE);
        callout_setfunc(&sme->sme_callout, sme_events_check, sme);
        callout_schedule(&sme->sme_callout, timo);
        sme->sme_flags |= SME_CALLOUT_INITIALIZED;
        DPRINTF(("%s: events framework initialized for '%s'\n",
            __func__, sme->sme_name));

        return error;
}

/*
 * sme_events_destroy:
 *
 *      + Destroys the event framework for this device: callout
 *        stopped, workqueue destroyed and callout mutex destroyed.
 */
void
sme_events_destroy(struct sysmon_envsys *sme)
{
        KASSERT(mutex_owned(&sme->sme_mtx));

        callout_stop(&sme->sme_callout);
        workqueue_destroy(sme->sme_wq);
        mutex_destroy(&sme->sme_callout_mtx);
        callout_destroy(&sme->sme_callout);
        sme->sme_flags &= ~SME_CALLOUT_INITIALIZED;
        DPRINTF(("%s: events framework destroyed for '%s'\n",
            __func__, sme->sme_name));
}

/*
 * sme_events_check:
 *
 *      + Passes the events to the workqueue thread and stops
 *        the callout if the 'low-power' condition is triggered.
 */
void
sme_events_check(void *arg)
{
        struct sysmon_envsys *sme = arg;
        sme_event_t *see;
        uint64_t timo;

        KASSERT(sme != NULL);

        mutex_enter(&sme->sme_callout_mtx);
        LIST_FOREACH(see, &sme->sme_events_list, see_list) {
                workqueue_enqueue(sme->sme_wq, &see->see_wk, NULL);
                see->see_edata->flags |= ENVSYS_FNEED_REFRESH;
        }
        if (sme->sme_events_timeout)
                timo = sme->sme_events_timeout * hz;
        else
                timo = SME_EVTIMO;
        if (!sysmon_low_power)
                callout_schedule(&sme->sme_callout, timo);
        mutex_exit(&sme->sme_callout_mtx);
}

/*
 * sme_events_worker:
 *
 *      + workqueue thread that checks if there's a critical condition
 *        and sends an event if it was triggered.
 */
void
sme_events_worker(struct work *wk, void *arg)
{
        const struct sme_description_table *sdt = NULL;
        const struct sme_sensor_event *sse = sme_sensor_event;
        sme_event_t *see = (void *)wk;
        struct sysmon_envsys *sme = see->see_sme;
        envsys_data_t *edata = see->see_edata;
        int i, state = 0;

        KASSERT(wk == &see->see_wk);
        KASSERT(sme != NULL || edata != NULL);

        mutex_enter(&sme->sme_mtx);
        if ((see->see_flags & SEE_EVENT_WORKING) == 0)
                see->see_flags |= SEE_EVENT_WORKING;
        /* 
         * sme_events_check marks the sensors to make us refresh them here.
         * Don't refresh if the driver uses its own method for refreshing.
         */
        if ((sme->sme_flags & SME_DISABLE_REFRESH) == 0) {
                if ((edata->flags & ENVSYS_FNEED_REFRESH) != 0) {
                        /* refresh sensor in device */
                        (*sme->sme_refresh)(sme, edata);
                        edata->flags &= ~ENVSYS_FNEED_REFRESH;
                }
        }

        DPRINTFOBJ(("%s: (%s) desc=%s sensor=%d type=%d state=%d units=%d "
            "value_cur=%d\n", __func__, sme->sme_name, edata->desc,
            edata->sensor, see->see_type, edata->state, edata->units,
            edata->value_cur));

        /* skip the event if current sensor is in invalid state */
        if (edata->state == ENVSYS_SINVALID)
                goto out;

        switch (see->see_type) {
        /*
         * For range limits, if the driver claims responsibility for
         * limit/range checking, just user driver-supplied status.
         * Else calculate our own status.  Note that driver must
         * relinquish responsibility for ALL limits if there is even
         * one limit that it cannot handle!
         */
        case PENVSYS_EVENT_LIMITS:
        case PENVSYS_EVENT_CAPACITY:
#define __EXCEED_LIM(valid, lim, rel) \
                ((see->see_lims.sel_flags & (valid)) && \
                 (edata->value_cur rel (see->see_lims.lim)))

                if ((see->see_lims.sel_flags & PROP_DRIVER_LIMITS) == 0) {
                        if __EXCEED_LIM(PROP_CRITMIN | PROP_BATTCAP,
                                        sel_critmin, <)
                                edata->state = ENVSYS_SCRITUNDER;
                        else if __EXCEED_LIM(PROP_WARNMIN | PROP_BATTWARN, 
                                        sel_warnmin, <)
                                edata->state = ENVSYS_SWARNUNDER;
                        else if __EXCEED_LIM(PROP_CRITMAX, sel_critmax, >)
                                edata->state = ENVSYS_SCRITOVER;
                        else if __EXCEED_LIM(PROP_WARNMAX, sel_warnmax, >)
                                edata->state = ENVSYS_SWARNOVER;
                }
#undef  __EXCEED_LIM

                /*
                 * Send event if state has changed
                 */
                if (edata->state == see->see_evsent)
                        break;

                for (i = 0; sse[i].state != -1; i++)
                        if (sse[i].state == edata->state)
                                break;

                if (sse[i].state == -1)
                        break;

                if (edata->state == ENVSYS_SVALID)
                        sysmon_penvsys_event(&see->see_pes,
                                             PENVSYS_EVENT_NORMAL);
                else
                        sysmon_penvsys_event(&see->see_pes, sse[i].event);

                see->see_evsent = edata->state;

                break;

        /*
         * Send PENVSYS_EVENT_CRITICAL event if:
         *      State has gone from non-CRITICAL to CRITICAL,
         *      State remains CRITICAL and value has changed, or
         *      State has returned from CRITICAL to non-CRITICAL
         */
        case PENVSYS_EVENT_CRITICAL:
                if (edata->state == ENVSYS_SVALID &&
                    see->see_evsent != 0) {
                        sysmon_penvsys_event(&see->see_pes,
                                             PENVSYS_EVENT_NORMAL);
                        see->see_evsent = 0;
                } else if (edata->state == ENVSYS_SCRITICAL &&
                    see->see_evsent != edata->value_cur) {
                        sysmon_penvsys_event(&see->see_pes,
                                             PENVSYS_EVENT_CRITICAL);
                        see->see_evsent = edata->value_cur;
                }
                break;

        /*
         * if value_cur is not normal (battery) or online (drive),
         * send the event...
         */
        case PENVSYS_EVENT_STATE_CHANGED:
                /* 
                 * the state has not been changed, just ignore the event.
                 */
                if (edata->value_cur == see->see_evsent)
                        break;

                switch (edata->units) {
                case ENVSYS_DRIVE:
                        sdt = sme_get_description_table(SME_DESC_DRIVE_STATES);
                        state = ENVSYS_DRIVE_ONLINE;
                        break;
                case ENVSYS_BATTERY_CAPACITY:
                        sdt = sme_get_description_table(
                            SME_DESC_BATTERY_CAPACITY);
                        state = ENVSYS_BATTERY_CAPACITY_NORMAL;
                        break;
                default:
                        panic("%s: bad units for PENVSYS_EVENT_STATE_CHANGED",
                            __func__);
                }

                for (i = 0; sdt[i].type != -1; i++)
                        if (sdt[i].type == edata->value_cur)
                                break;

                if (sdt[i].type == -1)
                        break;

                /* 
                 * copy current state description.
                 */
                (void)strlcpy(see->see_pes.pes_statedesc, sdt[i].desc,
                    sizeof(see->see_pes.pes_statedesc));

                if (edata->value_cur == state)
                        /*
                         * state returned to normal condition
                         */
                        sysmon_penvsys_event(&see->see_pes,
                                             PENVSYS_EVENT_NORMAL);
                else
                        /*
                         * state changed to abnormal condition
                         */
                        sysmon_penvsys_event(&see->see_pes, see->see_type);

                see->see_evsent = edata->value_cur;

                /* 
                 * There's no need to continue if it's a drive sensor.
                 */
                if (edata->units == ENVSYS_DRIVE)
                        break;

                /*
                 * Check if the system is running in low power and send the
                 * event to powerd (if running) or shutdown the system
                 * otherwise.
                 */
                if (!sysmon_low_power && sme_event_check_low_power()) {
                        struct penvsys_state pes;

                        /*
                         * Stop the callout and send the 'low-power' event.
                         */
                        sysmon_low_power = true;
                        callout_stop(&sme->sme_callout);
                        pes.pes_type = PENVSYS_TYPE_BATTERY;
                        sysmon_penvsys_event(&pes, PENVSYS_EVENT_LOW_POWER);
                }
                break;
        default:
                panic("%s: invalid event type %d", __func__, see->see_type);
        }

out:
        see->see_flags &= ~SEE_EVENT_WORKING;
        cv_broadcast(&sme->sme_condvar);
        mutex_exit(&sme->sme_mtx);
}

/*
 * Returns true if the system is in low power state: an AC adapter
 * is OFF and all batteries are in LOW/CRITICAL state.
 */
static bool
sme_event_check_low_power(void)
{
        if (!sme_acadapter_check())
                return false;

        return sme_battery_check();
}

/*
 * Called with the sysmon_envsys device mtx held through the
 * workqueue thread.
 */
static bool
sme_acadapter_check(void)
{
        struct sysmon_envsys *sme;
        envsys_data_t *edata;
        bool dev = false, sensor = false;

        LIST_FOREACH(sme, &sysmon_envsys_list, sme_list) {
                if (sme->sme_class == SME_CLASS_ACADAPTER) {
                        dev = true;
                        break;
                }
        }

        /*
         * No AC Adapter devices were found.
         */
        if (!dev)
                return false;

        /*
         * Check if there's an AC adapter device connected.
         */
        TAILQ_FOREACH(edata, &sme->sme_sensors_list, sensors_head) {
                if (edata->units == ENVSYS_INDICATOR) {
                        sensor = true;
                        /* refresh current sensor */
                        (*sme->sme_refresh)(sme, edata);
                        if (edata->value_cur)
                                return false;
                }
        }

        if (!sensor)
                return false;

        /* 
         * AC adapter found and not connected.
         */
        return true;
}

/*
 * Called with the sysmon_envsys device mtx held through the
 * workqueue thread.
 */
static bool
sme_battery_check(void)
{
        struct sysmon_envsys *sme;
        envsys_data_t *edata;
        int batteriesfound = 0;
        bool present, batterycap, batterycharge;

        /*
         * Check for battery devices and its state.
         */
        LIST_FOREACH(sme, &sysmon_envsys_list, sme_list) {
                if (sme->sme_class != SME_CLASS_BATTERY)
                        continue;

                present = true;
                TAILQ_FOREACH(edata, &sme->sme_sensors_list, sensors_head) {
                        if (edata->units == ENVSYS_INDICATOR &&
                            !edata->value_cur) {
                                present = false;
                                break;
                        }
                }
                if (!present)
                        continue;
                /*
                 * We've found a battery device...
                 */
                batteriesfound++;
                batterycap = batterycharge = false;
                TAILQ_FOREACH(edata, &sme->sme_sensors_list, sensors_head) {
                        if (edata->units == ENVSYS_BATTERY_CAPACITY) {
                                batterycap = true;
                                if (!sme_battery_critical(edata))
                                        return false;
                        } else if (edata->units == ENVSYS_BATTERY_CHARGE) {
                                batterycharge = true;
                                if (edata->value_cur)
                                        return false;
                        }
                }
                if (!batterycap || !batterycharge)
                        return false;
        }

        if (!batteriesfound)
                return false;

        /*
         * All batteries in low/critical capacity and discharging.
         */
        return true;
}

static bool
sme_battery_critical(envsys_data_t *edata)
{
        if (edata->value_cur == ENVSYS_BATTERY_CAPACITY_CRITICAL ||
            edata->value_cur == ENVSYS_BATTERY_CAPACITY_LOW)
                return true;

        return false;
}