sys/dev/acpica/acpi_cmbat.c

   1 /*-
   2  * Copyright (c) 2000 Munehiro Matsuda
   3  * Copyright (c) 2000 Takanori Watanabe
   4  * Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@FreeBSD.org>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD$
  29  */
  30
  31 #include "opt_acpi.h"
  32 #include <sys/param.h>
  33 #include <sys/kernel.h>
  34 #include <sys/bus.h>
  35 #include <sys/ioccom.h>
  36 #include <sys/conf.h>
  37
  38 #include <machine/bus.h>
  39 #include <machine/resource.h>
  40 #include <sys/rman.h>
  41 #include <sys/malloc.h>
  42
  43 #include  "acpi.h"
  44
  45 #include <dev/acpica/acpivar.h>
  46 #include <dev/acpica/acpiio.h>
  47
  48 MALLOC_DEFINE(M_ACPICMBAT, "acpicmbat", "ACPI control method battery data");
  49
  50 #define CMBAT_POLLRATE  (60 * hz)
  51
  52 /*
  53  * Hooks for the ACPI CA debugging infrastructure
  54  */
  55 #define _COMPONENT      ACPI_BATTERY
  56 MODULE_NAME("BATTERY")
  57
  58 #define ACPI_BATTERY_BST_CHANGE 0x80
  59 #define ACPI_BATTERY_BIF_CHANGE 0x81
  60
  61 #define PKG_GETINT(res, tmp, idx, dest, label) do {                     \
  62         tmp = &res->Package.Elements[idx];                              \
  63         if (tmp == NULL) {                                              \
  64                 device_printf(dev, "%s: PKG_GETINT idx = %d\n.",        \
  65                     __func__, idx);                                     \
  66                 goto label;                                             \
  67         }                                                               \
  68         if (tmp->Type != ACPI_TYPE_INTEGER)                             \
  69                 goto label;                                             \
  70         dest = tmp->Integer.Value;                                      \
  71 } while (0)
  72
  73 #define PKG_GETSTR(res, tmp, idx, dest, size, label) do {               \
  74         size_t  length;                                                 \
  75         length = size;                                                  \
  76         tmp = &res->Package.Elements[idx];                              \
  77         if (tmp == NULL) {                                              \
  78                 device_printf(dev, "%s: PKG_GETSTR idx = %d\n.",        \
  79                     __func__, idx);                                     \
  80                 goto label;                                             \
  81         }                                                               \
  82         bzero(dest, sizeof(dest));                                      \
  83         switch (tmp->Type) {                                            \
  84         case ACPI_TYPE_STRING:                                          \
  85                 if (tmp->String.Length < length) {                      \
  86                         length = tmp->String.Length;                    \
  87                 }                                                       \
  88                 strncpy(dest, tmp->String.Pointer, length);             \
  89                 break;                                                  \
  90         case ACPI_TYPE_BUFFER:                                          \
  91                 if (tmp->Buffer.Length < length) {                      \
  92                         length = tmp->Buffer.Length;                    \
  93                 }                                                       \
  94                 strncpy(dest, tmp->Buffer.Pointer, length);             \
  95                 break;                                                  \
  96         default:                                                        \
  97                 goto label;                                             \
  98         }                                                               \
  99         dest[sizeof(dest)-1] = '\0';                                    \
 100 } while (0)
 101
 102 #define CMBAT_DPRINT(dev, x...) do {                                    \
 103         if (acpi_get_verbose(acpi_device_get_parent_softc(dev)))        \
 104                 device_printf(dev, x);                                  \
 105 } while (0)
 106
 107 struct acpi_cmbat_softc {
 108         device_t        dev;
 109
 110         struct acpi_bif bif;
 111         struct acpi_bst bst;
 112         ACPI_BUFFER     bif_buffer;
 113         ACPI_BUFFER     bst_buffer;
 114         struct timespec bif_lastupdated;
 115         struct timespec bst_lastupdated;
 116
 117         int             not_present;
 118         int             cap;
 119         int             min;
 120         int             full_charge_time;
 121
 122         struct callout_handle cmbat_timeout;
 123 };
 124
 125 static struct timespec   acpi_cmbat_info_lastupdated;
 126
 127 /* XXX: devclass_get_maxunit() don't give us the current allocated units... */
 128 static int               acpi_cmbat_units = 0;
 129
 130 static void              acpi_cmbat_timeout(void *);
 131 static int               acpi_cmbat_info_expired(struct timespec *);
 132 static void              acpi_cmbat_info_updated(struct timespec *);
 133 static void              acpi_cmbat_get_bst(void *);
 134 static void              acpi_cmbat_get_bif(void *);
 135 static void              acpi_cmbat_notify_handler(ACPI_HANDLE, UINT32, void *);
 136 static int               acpi_cmbat_probe(device_t);
 137 static int               acpi_cmbat_attach(device_t);
 138 static int               acpi_cmbat_resume(device_t);
 139 static int               acpi_cmbat_ioctl(u_long, caddr_t, void *);
 140 static int               acpi_cmbat_get_total_battinfo(struct acpi_battinfo *);
 141
 142 /*
 143  * Poll the battery info.
 144  */
 145 static void
 146 acpi_cmbat_timeout(void *context)
 147 {
 148         device_t        dev;
 149         struct acpi_cmbat_softc *sc;
 150
 151         dev = (device_t)context;
 152         sc = device_get_softc(dev);
 153
 154         AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
 155         sc->cmbat_timeout = timeout(acpi_cmbat_timeout, dev, CMBAT_POLLRATE);
 156 }
 157
 158 static __inline int
 159 acpi_cmbat_info_expired(struct timespec *lastupdated)
 160 {
 161         struct timespec curtime;
 162
 163         if (lastupdated == NULL) {
 164                 return (1);
 165         }
 166
 167         if (!timespecisset(lastupdated)) {
 168                 return (1);
 169         }
 170
 171         getnanotime(&curtime);
 172         timespecsub(&curtime, lastupdated);
 173         return ((curtime.tv_sec < 0 || curtime.tv_sec > acpi_battery_get_info_expire()));
 174 }
 175
 176
 177 static __inline void
 178 acpi_cmbat_info_updated(struct timespec *lastupdated)
 179 {
 180
 181         if (lastupdated != NULL) {
 182                 getnanotime(lastupdated);
 183         }
 184 }
 185
 186 static void
 187 acpi_cmbat_get_bst(void *context)
 188 {
 189         device_t        dev;
 190         struct acpi_cmbat_softc *sc;
 191         ACPI_STATUS     as;
 192         ACPI_OBJECT     *res, *tmp;
 193         ACPI_HANDLE     h;
 194
 195         dev = context;
 196         sc = device_get_softc(dev);
 197         h = acpi_get_handle(dev);
 198
 199         if (!acpi_cmbat_info_expired(&sc->bst_lastupdated)) {
 200                 return;
 201         }
 202
 203         untimeout(acpi_cmbat_timeout, (caddr_t)dev, sc->cmbat_timeout);
 204 retry:
 205         if (sc->bst_buffer.Length == 0) {
 206                 if (sc->bst_buffer.Pointer != NULL) {
 207                         free(sc->bst_buffer.Pointer, M_ACPICMBAT);
 208                         sc->bst_buffer.Pointer = NULL;
 209                 }
 210                 as = AcpiEvaluateObject(h, "_BST", NULL, &sc->bst_buffer);
 211                 if (as != AE_BUFFER_OVERFLOW) {
 212                         CMBAT_DPRINT(dev, "CANNOT FOUND _BST - %s\n",
 213                             AcpiFormatException(as));
 214                         goto end;
 215                 }
 216
 217                 sc->bst_buffer.Pointer = malloc(sc->bst_buffer.Length, M_ACPICMBAT, M_NOWAIT);
 218                 if (sc->bst_buffer.Pointer == NULL) {
 219                         device_printf(dev, "malloc failed");
 220                         goto end;
 221                 }
 222         }
 223
 224         bzero(sc->bst_buffer.Pointer, sc->bst_buffer.Length);
 225         as = AcpiEvaluateObject(h, "_BST", NULL, &sc->bst_buffer);
 226
 227         if (as == AE_BUFFER_OVERFLOW) {
 228                 if (sc->bst_buffer.Pointer != NULL) {
 229                         free(sc->bst_buffer.Pointer, M_ACPICMBAT);
 230                         sc->bst_buffer.Pointer = NULL;
 231                 }
 232                 CMBAT_DPRINT(dev, "bst size changed to %d\n", sc->bst_buffer.Length);
 233                 sc->bst_buffer.Length = 0;
 234                 goto retry;
 235         } else if (as != AE_OK) {
 236                 CMBAT_DPRINT(dev, "CANNOT FOUND _BST - %s\n",
 237                     AcpiFormatException(as));
 238                 goto end;
 239         }
 240
 241         res = (ACPI_OBJECT *)sc->bst_buffer.Pointer;
 242
 243         if ((res->Type != ACPI_TYPE_PACKAGE) || (res->Package.Count != 4)) {
 244                 CMBAT_DPRINT(dev, "Battery status corrupted\n");
 245                 goto end;
 246         }
 247
 248         PKG_GETINT(res, tmp, 0, sc->bst.state, end);
 249         PKG_GETINT(res, tmp, 1, sc->bst.rate, end);
 250         PKG_GETINT(res, tmp, 2, sc->bst.cap, end);
 251         PKG_GETINT(res, tmp, 3, sc->bst.volt, end);
 252         acpi_cmbat_info_updated(&sc->bst_lastupdated);
 253 end:
 254         sc->cmbat_timeout = timeout(acpi_cmbat_timeout, dev, CMBAT_POLLRATE);
 255 }
 256
 257 static void
 258 acpi_cmbat_get_bif(void *context)
 259 {
 260         device_t        dev;
 261         struct acpi_cmbat_softc *sc;
 262         ACPI_STATUS     as;
 263         ACPI_OBJECT     *res, *tmp;
 264         ACPI_HANDLE     h;
 265
 266         dev = context;
 267         sc = device_get_softc(dev);
 268         h = acpi_get_handle(dev);
 269
 270         if (!acpi_cmbat_info_expired(&sc->bif_lastupdated)) {
 271                 return;
 272         }
 273
 274         untimeout(acpi_cmbat_timeout, (caddr_t)dev, sc->cmbat_timeout);
 275 retry:
 276         if (sc->bif_buffer.Length == 0) {
 277                 if (sc->bif_buffer.Pointer != NULL) {
 278                         free(sc->bif_buffer.Pointer, M_ACPICMBAT);
 279                         sc->bif_buffer.Pointer = NULL;
 280                 }
 281                 as = AcpiEvaluateObject(h, "_BIF", NULL, &sc->bif_buffer);
 282                 if (as != AE_BUFFER_OVERFLOW) {
 283                         CMBAT_DPRINT(dev, "CANNOT FOUND _BIF - %s\n",
 284                             AcpiFormatException(as));
 285                         goto end;
 286                 }
 287
 288                 sc->bif_buffer.Pointer = malloc(sc->bif_buffer.Length, M_ACPICMBAT, M_NOWAIT);
 289                 if (sc->bif_buffer.Pointer == NULL) {
 290                         device_printf(dev, "malloc failed");
 291                         goto end;
 292                 }
 293         }
 294
 295         bzero(sc->bif_buffer.Pointer, sc->bif_buffer.Length);
 296         as = AcpiEvaluateObject(h, "_BIF", NULL, &sc->bif_buffer);
 297
 298         if (as == AE_BUFFER_OVERFLOW) {
 299                 if (sc->bif_buffer.Pointer != NULL) {
 300                         free(sc->bif_buffer.Pointer, M_ACPICMBAT);
 301                         sc->bif_buffer.Pointer = NULL;
 302                 }
 303                 CMBAT_DPRINT(dev, "bif size changed to %d\n", sc->bif_buffer.Length);
 304                 sc->bif_buffer.Length = 0;
 305                 goto retry;
 306         } else if (as != AE_OK) {
 307                 CMBAT_DPRINT(dev, "CANNOT FOUND _BIF - %s\n",
 308                     AcpiFormatException(as));
 309                 goto end;
 310         }
 311
 312         res = (ACPI_OBJECT *)sc->bif_buffer.Pointer;
 313
 314         if ((res->Type != ACPI_TYPE_PACKAGE) || (res->Package.Count != 13)) {
 315                 CMBAT_DPRINT(dev, "Battery info corrupted\n");
 316                 goto end;
 317         }
 318
 319         PKG_GETINT(res, tmp,  0, sc->bif.unit, end);
 320         PKG_GETINT(res, tmp,  1, sc->bif.dcap, end);
 321         PKG_GETINT(res, tmp,  2, sc->bif.lfcap, end);
 322         PKG_GETINT(res, tmp,  3, sc->bif.btech, end);
 323         PKG_GETINT(res, tmp,  4, sc->bif.dvol, end);
 324         PKG_GETINT(res, tmp,  5, sc->bif.wcap, end);
 325         PKG_GETINT(res, tmp,  6, sc->bif.lcap, end);
 326         PKG_GETINT(res, tmp,  7, sc->bif.gra1, end);
 327         PKG_GETINT(res, tmp,  8, sc->bif.gra2, end);
 328         PKG_GETSTR(res, tmp,  9, sc->bif.model, ACPI_CMBAT_MAXSTRLEN, end);
 329         PKG_GETSTR(res, tmp, 10, sc->bif.serial, ACPI_CMBAT_MAXSTRLEN, end);
 330         PKG_GETSTR(res, tmp, 11, sc->bif.type, ACPI_CMBAT_MAXSTRLEN, end);
 331         PKG_GETSTR(res, tmp, 12, sc->bif.oeminfo, ACPI_CMBAT_MAXSTRLEN, end);
 332         acpi_cmbat_info_updated(&sc->bif_lastupdated);
 333 end:
 334         sc->cmbat_timeout = timeout(acpi_cmbat_timeout, dev, CMBAT_POLLRATE);
 335 }
 336
 337 static void
 338 acpi_cmbat_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
 339 {
 340         device_t        dev;
 341         struct acpi_cmbat_softc *sc;
 342
 343         dev = (device_t)context;
 344         if ((sc = device_get_softc(dev)) == NULL) {
 345                 return;
 346         }
 347
 348         switch (notify) {
 349         case ACPI_BATTERY_BST_CHANGE:
 350                 timespecclear(&sc->bst_lastupdated);
 351                 break;
 352         case ACPI_BATTERY_BIF_CHANGE:
 353                 timespecclear(&sc->bif_lastupdated);
 354                 AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
 355                 break;
 356         default:
 357                 break;
 358         }
 359 }
 360
 361 static int
 362 acpi_cmbat_probe(device_t dev)
 363 {
 364
 365         if ((acpi_get_type(dev) == ACPI_TYPE_DEVICE) &&
 366             acpi_MatchHid(dev, "PNP0C0A")) {
 367                 /*
 368                  * Set device description.
 369                  */
 370                 device_set_desc(dev, "Control method Battery");
 371                 return (0);
 372         }
 373         return (ENXIO);
 374 }
 375
 376 static int
 377 acpi_cmbat_attach(device_t dev)
 378 {
 379         int             error;
 380         ACPI_HANDLE     handle;
 381         struct acpi_cmbat_softc *sc;
 382
 383         if ((sc = device_get_softc(dev)) == NULL) {
 384                 return (ENXIO);
 385         }
 386
 387         handle = acpi_get_handle(dev);
 388
 389         AcpiInstallNotifyHandler(handle, ACPI_DEVICE_NOTIFY,
 390                                  acpi_cmbat_notify_handler, dev);
 391
 392         bzero(&sc->bif_buffer, sizeof(sc->bif_buffer));
 393         bzero(&sc->bst_buffer, sizeof(sc->bst_buffer));
 394         sc->dev = dev;
 395
 396         timespecclear(&sc->bif_lastupdated);
 397         timespecclear(&sc->bst_lastupdated);
 398
 399         if (acpi_cmbat_units == 0) {
 400                 if ((error = acpi_register_ioctl(ACPIIO_CMBAT_GET_BIF,
 401                                 acpi_cmbat_ioctl, NULL)) != 0) {
 402                         return (error);
 403                 }
 404                 if ((error = acpi_register_ioctl(ACPIIO_CMBAT_GET_BST,
 405                                 acpi_cmbat_ioctl, NULL)) != 0) {
 406                         return (error);
 407                 }
 408         }
 409
 410         if ((error = acpi_battery_register(ACPI_BATT_TYPE_CMBAT,
 411                         acpi_cmbat_units)) != 0) {
 412                 return (error);
 413         }
 414
 415         acpi_cmbat_units++;
 416         timespecclear(&acpi_cmbat_info_lastupdated);
 417
 418         AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
 419         return (0);
 420 }
 421
 422 static int
 423 acpi_cmbat_resume(device_t dev)
 424 {
 425
 426         AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
 427         return (0);
 428 }
 429
 430 static device_method_t acpi_cmbat_methods[] = {
 431         /* Device interface */
 432         DEVMETHOD(device_probe,         acpi_cmbat_probe),
 433         DEVMETHOD(device_attach,        acpi_cmbat_attach),
 434         DEVMETHOD(device_resume,        acpi_cmbat_resume),
 435
 436         {0, 0}
 437 };
 438
 439 static driver_t acpi_cmbat_driver = {
 440         "acpi_cmbat",
 441         acpi_cmbat_methods,
 442         sizeof(struct acpi_cmbat_softc),
 443 };
 444
 445 static devclass_t acpi_cmbat_devclass;
 446 DRIVER_MODULE(acpi_cmbat, acpi, acpi_cmbat_driver, acpi_cmbat_devclass, 0, 0);
 447
 448 static int
 449 acpi_cmbat_ioctl(u_long cmd, caddr_t addr, void *arg)
 450 {
 451         device_t        dev;
 452         union acpi_battery_ioctl_arg *ioctl_arg;
 453         struct acpi_cmbat_softc *sc;
 454         struct acpi_bif *bifp;
 455         struct acpi_bst *bstp;
 456
 457         ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
 458         if ((dev = devclass_get_device(acpi_cmbat_devclass,
 459                         ioctl_arg->unit)) == NULL) {
 460                 return (ENXIO);
 461         }
 462
 463         if ((sc = device_get_softc(dev)) == NULL) {
 464                 return (ENXIO);
 465         }
 466
 467         switch (cmd) {
 468         case ACPIIO_CMBAT_GET_BIF:
 469                 acpi_cmbat_get_bif(dev);
 470                 bifp = &ioctl_arg->bif;
 471                 bifp->unit = sc->bif.unit;
 472                 bifp->dcap = sc->bif.dcap;
 473                 bifp->lfcap = sc->bif.lfcap;
 474                 bifp->btech = sc->bif.btech;
 475                 bifp->dvol = sc->bif.dvol;
 476                 bifp->wcap = sc->bif.wcap;
 477                 bifp->lcap = sc->bif.lcap;
 478                 bifp->gra1 = sc->bif.gra1;
 479                 bifp->gra2 = sc->bif.gra2;
 480                 strncpy(bifp->model, sc->bif.model, sizeof(sc->bif.model));
 481                 strncpy(bifp->serial, sc->bif.serial, sizeof(sc->bif.serial));
 482                 strncpy(bifp->type, sc->bif.type, sizeof(sc->bif.type));
 483                 strncpy(bifp->oeminfo, sc->bif.oeminfo, sizeof(sc->bif.oeminfo));
 484                 break;
 485
 486         case ACPIIO_CMBAT_GET_BST:
 487                 acpi_cmbat_get_bst(dev);
 488                 bstp = &ioctl_arg->bst;
 489                 bstp->state = sc->bst.state;
 490                 bstp->rate = sc->bst.rate;
 491                 bstp->cap = sc->bst.cap;
 492                 bstp->volt = sc->bst.volt;
 493                 break;
 494         }
 495
 496         return (0);
 497 }
 498
 499 static int
 500 acpi_cmbat_get_total_battinfo(struct acpi_battinfo *battinfo)
 501 {
 502         int             i;
 503         int             error;
 504         int             batt_stat;
 505         int             valid_rate, valid_units;
 506         int             cap, min;
 507         int             total_cap, total_min, total_full;
 508         device_t        dev;
 509         struct acpi_cmbat_softc *sc;
 510         static int      bat_units = 0;
 511         static struct acpi_cmbat_softc **bat = NULL;
 512
 513         cap = min = -1;
 514         batt_stat = ACPI_BATT_STAT_NOT_PRESENT;
 515         error = 0;
 516
 517         /* Allocate array of softc pointers */
 518         if (bat_units != acpi_cmbat_units) {
 519                 if (bat != NULL) {
 520                         free(bat, M_ACPICMBAT);
 521                         bat = NULL;
 522                 }
 523                 bat_units = 0;
 524         }
 525         if (bat == NULL) {
 526                 bat_units = acpi_cmbat_units;
 527                 bat = malloc(sizeof(struct acpi_cmbat_softc *) * bat_units,
 528                              M_ACPICMBAT, M_NOWAIT);
 529                 if (bat == NULL) {
 530                         error = ENOMEM;
 531                         goto out;
 532                 }
 533
 534                 /* Collect softc pointers */
 535                 for (i = 0; i < acpi_cmbat_units; i++) {
 536                         if ((dev = devclass_get_device(acpi_cmbat_devclass, i)) == NULL) {
 537                                 error = ENXIO;
 538                                 goto out;
 539                         }
 540
 541                         if ((sc = device_get_softc(dev)) == NULL) {
 542                                 error = ENXIO;
 543                                 goto out;
 544                         }
 545
 546                         bat[i] = sc;
 547                 }
 548         }
 549
 550         /* Get battery status, valid rate and valid units */
 551         batt_stat = valid_rate = valid_units = 0;
 552         for (i = 0; i < acpi_cmbat_units; i++) {
 553                 bat[i]->not_present = 0;
 554                 acpi_cmbat_get_bst(bat[i]->dev);
 555
 556                 /* If battey not installed, we get strange values */
 557                 if (bat[i]->bst.state >= ACPI_BATT_STAT_MAX ||
 558                     bat[i]->bst.cap == 0xffffffff ||
 559                     bat[i]->bst.volt == 0xffffffff ||
 560                     bat[i]->bif.lfcap == 0) {
 561                         bat[i]->not_present = 1;
 562                         continue;
 563                 }
 564
 565                 valid_units++;
 566
 567                 bat[i]->cap = 100 * bat[i]->bst.cap / bat[i]->bif.lfcap;
 568
 569                 batt_stat |= bat[i]->bst.state;
 570
 571                 if (bat[i]->bst.rate > 0) {
 572                         /*
 573                          * XXX Hack to calculate total battery time.
 574                          * Systems with 2 or more battries, they may get used
 575                          * one by one, thus bst.rate is set only to the one
 576                          * in use. For remaining batteries bst.rate = 0, which
 577                          * makes it impossible to calculate remaining time.
 578                          * Some other systems may need sum of bst.rate in
 579                          * dis-charging state.
 580                          * There for we sum up the bst.rate that is valid
 581                          * (in dis-charging state), and use the sum to
 582                          * calcutate remaining batteries' time.
 583                          */
 584                         if (bat[i]->bst.state & ACPI_BATT_STAT_DISCHARG) {
 585                                 valid_rate += bat[i]->bst.rate;
 586                         }
 587                 }
 588         }
 589
 590         /* Calculate total battery capacity and time */
 591         total_cap = total_min = total_full = 0;
 592         for (i = 0; i < acpi_cmbat_units; i++) {
 593                 if (bat[i]->not_present) {
 594                         continue;
 595                 }
 596
 597                 if (valid_rate > 0) {
 598                         /* Use the sum of bst.rate */
 599                         bat[i]->min = 60 * bat[i]->bst.cap / valid_rate;
 600                 } else if (bat[i]->full_charge_time > 0) {
 601                         bat[i]->min = (bat[i]->full_charge_time * bat[i]->cap) / 100;
 602                 } else {
 603                         /* Couldn't find valid rate and full battery time */
 604                         bat[i]->min = 0;
 605                 }
 606                 total_min += bat[i]->min;
 607                 total_cap += bat[i]->cap;
 608                 total_full += bat[i]->full_charge_time;
 609         }
 610
 611         /* Battery life */
 612         if (valid_units == 0) {
 613                 cap = -1;
 614                 batt_stat = ACPI_BATT_STAT_NOT_PRESENT;
 615         } else {
 616                 cap = total_cap / valid_units;
 617         }
 618
 619         /* Battery time */
 620         if (valid_units == 0) {
 621                 min = -1;
 622         } else if (valid_rate == 0 || (batt_stat & ACPI_BATT_STAT_CHARGING)) {
 623                 if (total_full == 0) {
 624                         min = -1;
 625                 } else {
 626                         min = (total_full * cap) / 100;
 627                 }
 628         } else {
 629                 min = total_min;
 630         }
 631
 632         acpi_cmbat_info_updated(&acpi_cmbat_info_lastupdated);
 633 out:
 634         battinfo->cap = cap;
 635         battinfo->min = min;
 636         battinfo->state = batt_stat;
 637
 638         return (error);
 639 }
 640
 641 /*
 642  * Public interfaces.
 643  */
 644
 645 int
 646 acpi_cmbat_get_battinfo(int unit, struct acpi_battinfo *battinfo)
 647 {
 648         int             error;
 649         device_t        dev;
 650         struct acpi_cmbat_softc *sc;
 651
 652         if (unit == -1) {
 653                 return (acpi_cmbat_get_total_battinfo(battinfo));
 654         }
 655
 656         if (acpi_cmbat_info_expired(&acpi_cmbat_info_lastupdated)) {
 657                 error = acpi_cmbat_get_total_battinfo(battinfo);
 658                 if (error) {
 659                         goto out;
 660                 }
 661         }
 662
 663         error = 0;
 664         if (unit >= acpi_cmbat_units) {
 665                 error = ENXIO;
 666                 goto out;
 667         }
 668
 669         if ((dev = devclass_get_device(acpi_cmbat_devclass, unit)) == NULL) {
 670                 error = ENXIO;
 671                 goto out;
 672         }
 673
 674         if ((sc = device_get_softc(dev)) == NULL) {
 675                 error = ENXIO;
 676                 goto out;
 677         }
 678
 679         if (sc->not_present) {
 680                 battinfo->cap = -1;
 681                 battinfo->min = -1;
 682                 battinfo->state = ACPI_BATT_STAT_NOT_PRESENT;
 683         } else {
 684                 battinfo->cap = sc->cap;
 685                 battinfo->min = sc->min;
 686                 battinfo->state = sc->bst.state;
 687         }
 688 out:
 689         return (error);
 690 }
 691