sys/platform/pc32/apm/apm.c

   1 /*
   2  * APM (Advanced Power Management) BIOS Device Driver
   3  *
   4  * Copyright (c) 1994 UKAI, Fumitoshi.
   5  * Copyright (c) 1994-1995 by HOSOKAWA, Tatsumi <hosokawa@jp.FreeBSD.org>
   6  * Copyright (c) 1996 Nate Williams <nate@FreeBSD.org>
   7  * Copyright (c) 1997 Poul-Henning Kamp <phk@FreeBSD.org>
   8  *
   9  * This software may be used, modified, copied, and distributed, in
  10  * both source and binary form provided that the above copyright and
  11  * these terms are retained. Under no circumstances is the author
  12  * responsible for the proper functioning of this software, nor does
  13  * the author assume any responsibility for damages incurred with its
  14  * use.
  15  *
  16  * Sep, 1994    Implemented on FreeBSD 1.1.5.1R (Toshiba AVS001WD)
  17  *
  18  * $FreeBSD: src/sys/i386/apm/apm.c,v 1.114.2.5 2002/11/02 04:41:50 iwasaki Exp $
  19  * $DragonFly: src/sys/platform/pc32/apm/apm.c,v 1.21 2006/12/23 00:27:03 swildner Exp $
  20  */
  21
  22 #include <sys/param.h>
  23 #include <sys/systm.h>
  24 #include <sys/eventhandler.h>
  25 #include <sys/conf.h>
  26 #include <sys/device.h>
  27 #include <sys/kernel.h>
  28 #include <sys/time.h>
  29 #include <sys/reboot.h>
  30 #include <sys/bus.h>
  31 #include <sys/selinfo.h>
  32 #include <sys/poll.h>
  33 #include <sys/fcntl.h>
  34 #include <sys/uio.h>
  35 #include <sys/signalvar.h>
  36 #include <sys/sysctl.h>
  37 #include <machine/apm_bios.h>
  38 #include <machine/segments.h>
  39 #include <machine/clock.h>
  40 #include <vm/vm.h>
  41 #include <vm/vm_param.h>
  42 #include <vm/pmap.h>
  43 #include <sys/syslog.h>
  44 #include <sys/thread2.h>
  45
  46 #include <machine/pc/bios.h>
  47 #include <machine/vm86.h>
  48
  49 #include <machine_base/apm/apm.h>
  50
  51 /* Used by the apm_saver screen saver module */
  52 int apm_display (int newstate);
  53 struct apm_softc apm_softc;
  54
  55 static void apm_resume (void);
  56 static int apm_bioscall(void);
  57 static int apm_check_function_supported (u_int version, u_int func);
  58
  59 static u_long   apm_version;
  60
  61 int     apm_evindex;
  62
  63 #define SCFLAG_ONORMAL  0x0000001
  64 #define SCFLAG_OCTL     0x0000002
  65 #define SCFLAG_OPEN     (SCFLAG_ONORMAL|SCFLAG_OCTL)
  66
  67 #define APMDEV(dev)     (minor(dev)&0x0f)
  68 #define APMDEV_NORMAL   0
  69 #define APMDEV_CTL      8
  70
  71 static struct apmhook   *hook[NAPM_HOOK];               /* XXX */
  72
  73 #define is_enabled(foo) ((foo) ? "enabled" : "disabled")
  74
  75 /* Map version number to integer (keeps ordering of version numbers) */
  76 #define INTVERSION(major, minor)        ((major)*100 + (minor))
  77
  78 static struct callout apm_timeout_ch;
  79
  80 static timeout_t apm_timeout;
  81 static d_open_t apmopen;
  82 static d_close_t apmclose;
  83 static d_write_t apmwrite;
  84 static d_ioctl_t apmioctl;
  85 static d_poll_t apmpoll;
  86
  87 #define CDEV_MAJOR 39
  88 static struct dev_ops apm_ops = {
  89         { "apm", CDEV_MAJOR, 0 },
  90         .d_open =       apmopen,
  91         .d_close =      apmclose,
  92         .d_write =      apmwrite,
  93         .d_ioctl =      apmioctl,
  94         .d_poll =       apmpoll,
  95 };
  96
  97 static int apm_suspend_delay = 1;
  98 static int apm_standby_delay = 1;
  99 static int apm_debug = 0;
 100
 101 #define APM_DPRINT(args...) do  {                                       \
 102         if (apm_debug) {                                                \
 103                 kprintf(args);                                          \
 104         }                                                               \
 105 } while (0)
 106
 107 SYSCTL_INT(_machdep, OID_AUTO, apm_suspend_delay, CTLFLAG_RW, &apm_suspend_delay, 1, "");
 108 SYSCTL_INT(_machdep, OID_AUTO, apm_standby_delay, CTLFLAG_RW, &apm_standby_delay, 1, "");
 109 SYSCTL_INT(_debug, OID_AUTO, apm_debug, CTLFLAG_RW, &apm_debug, 0, "");
 110
 111 /*
 112  * return  0 if the function successfull,
 113  * return  1 if the function unsuccessfull,
 114  * return -1 if the function unsupported.
 115  */
 116 static int
 117 apm_bioscall(void)
 118 {
 119         struct apm_softc *sc = &apm_softc;
 120         int error = 0;
 121         u_int apm_func = sc->bios.r.eax & 0xff;
 122
 123         if (!apm_check_function_supported(sc->intversion, apm_func)) {
 124                 APM_DPRINT("apm_bioscall: function 0x%x is not supported in v%d.%d\n",
 125                     apm_func, sc->majorversion, sc->minorversion);
 126                 return (-1);
 127         }
 128
 129         sc->bios_busy = 1;
 130         if (sc->connectmode == APM_PROT32CONNECT) {
 131                 set_bios_selectors(&sc->bios.seg,
 132                                    BIOSCODE_FLAG | BIOSDATA_FLAG);
 133                 error = bios32(&sc->bios.r,
 134                                sc->bios.entry, GSEL(GBIOSCODE32_SEL, SEL_KPL));
 135         } else {
 136                 error = bios16(&sc->bios, NULL);
 137         }
 138         sc->bios_busy = 0;
 139         return (error);
 140 }
 141
 142 /* check whether APM function is supported (1)  or not (0). */
 143 static int
 144 apm_check_function_supported(u_int version, u_int func)
 145 {
 146         /* except driver version */
 147         if (func == APM_DRVVERSION) {
 148                 return (1);
 149         }
 150
 151         switch (version) {
 152         case INTVERSION(1, 0):
 153                 if (func > APM_GETPMEVENT) {
 154                         return (0); /* not supported */
 155                 }
 156                 break;
 157         case INTVERSION(1, 1):
 158                 if (func > APM_ENGAGEDISENGAGEPM &&
 159                     func < APM_OEMFUNC) {
 160                         return (0); /* not supported */
 161                 }
 162                 break;
 163         case INTVERSION(1, 2):
 164                 break;
 165         }
 166
 167         return (1); /* supported */
 168 }
 169
 170 /* enable/disable power management */
 171 static int
 172 apm_enable_disable_pm(int enable)
 173 {
 174         struct apm_softc *sc = &apm_softc;
 175
 176         sc->bios.r.eax = (APM_BIOS << 8) | APM_ENABLEDISABLEPM;
 177
 178         if (sc->intversion >= INTVERSION(1, 1))
 179                 sc->bios.r.ebx  = PMDV_ALLDEV;
 180         else
 181                 sc->bios.r.ebx  = 0xffff;       /* APM version 1.0 only */
 182         sc->bios.r.ecx  = enable;
 183         sc->bios.r.edx = 0;
 184         return (apm_bioscall());
 185 }
 186
 187 /* register driver version (APM 1.1 or later) */
 188 static int
 189 apm_driver_version(int version)
 190 {
 191         struct apm_softc *sc = &apm_softc;
 192
 193         sc->bios.r.eax = (APM_BIOS << 8) | APM_DRVVERSION;
 194         sc->bios.r.ebx  = 0x0;
 195         sc->bios.r.ecx  = version;
 196         sc->bios.r.edx = 0;
 197
 198         if (apm_bioscall() == 0 && sc->bios.r.eax == version)
 199                 return (0);
 200
 201         /* Some old BIOSes don't return the connection version in %ax. */
 202         if (sc->bios.r.eax == ((APM_BIOS << 8) | APM_DRVVERSION))
 203                 return (0);
 204
 205         return (1);
 206 }
 207
 208 /* engage/disengage power management (APM 1.1 or later) */
 209 static int
 210 apm_engage_disengage_pm(int engage)
 211 {
 212         struct apm_softc *sc = &apm_softc;
 213
 214         sc->bios.r.eax = (APM_BIOS << 8) | APM_ENGAGEDISENGAGEPM;
 215         sc->bios.r.ebx = PMDV_ALLDEV;
 216         sc->bios.r.ecx = engage;
 217         sc->bios.r.edx = 0;
 218         return (apm_bioscall());
 219 }
 220
 221 /* get PM event */
 222 static u_int
 223 apm_getevent(void)
 224 {
 225         struct apm_softc *sc = &apm_softc;
 226
 227         sc->bios.r.eax = (APM_BIOS << 8) | APM_GETPMEVENT;
 228
 229         sc->bios.r.ebx = 0;
 230         sc->bios.r.ecx = 0;
 231         sc->bios.r.edx = 0;
 232         if (apm_bioscall())
 233                 return (PMEV_NOEVENT);
 234         return (sc->bios.r.ebx & 0xffff);
 235 }
 236
 237 /* suspend entire system */
 238 static int
 239 apm_suspend_system(int state)
 240 {
 241         struct apm_softc *sc = &apm_softc;
 242
 243         sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
 244         sc->bios.r.ebx = PMDV_ALLDEV;
 245         sc->bios.r.ecx = state;
 246         sc->bios.r.edx = 0;
 247
 248         if (apm_bioscall()) {
 249                 kprintf("Entire system suspend failure: errcode = %d\n",
 250                        0xff & (sc->bios.r.eax >> 8));
 251                 return 1;
 252         }
 253         return 0;
 254 }
 255
 256 /* Display control */
 257 /*
 258  * Experimental implementation: My laptop machine can't handle this function
 259  * If your laptop can control the display via APM, please inform me.
 260  *                            HOSOKAWA, Tatsumi <hosokawa@jp.FreeBSD.org>
 261  */
 262 int
 263 apm_display(int newstate)
 264 {
 265         struct apm_softc *sc = &apm_softc;
 266
 267         sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
 268         sc->bios.r.ebx = PMDV_DISP0;
 269         sc->bios.r.ecx = newstate ? PMST_APMENABLED:PMST_SUSPEND;
 270         sc->bios.r.edx = 0;
 271         if (apm_bioscall() == 0) {
 272                 return 0;
 273         }
 274
 275         /* If failed, then try to blank all display devices instead. */
 276         sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
 277         sc->bios.r.ebx = PMDV_DISPALL;  /* all display devices */
 278         sc->bios.r.ecx = newstate ? PMST_APMENABLED:PMST_SUSPEND;
 279         sc->bios.r.edx = 0;
 280         if (apm_bioscall() == 0) {
 281                 return 0;
 282         }
 283         kprintf("Display off failure: errcode = %d\n",
 284                0xff & (sc->bios.r.eax >> 8));
 285         return 1;
 286 }
 287
 288 /*
 289  * Turn off the entire system.
 290  */
 291 static void
 292 apm_power_off(void *junk, int howto)
 293 {
 294         struct apm_softc *sc = &apm_softc;
 295
 296         /* Not halting powering off, or not active */
 297         if (!(howto & RB_POWEROFF) || !apm_softc.active)
 298                 return;
 299         sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
 300         sc->bios.r.ebx = PMDV_ALLDEV;
 301         sc->bios.r.ecx = PMST_OFF;
 302         sc->bios.r.edx = 0;
 303         apm_bioscall();
 304 }
 305
 306 /* APM Battery low handler */
 307 static void
 308 apm_battery_low(void)
 309 {
 310         kprintf("\007\007 * * * BATTERY IS LOW * * * \007\007");
 311 }
 312
 313 /* APM hook manager */
 314 static struct apmhook *
 315 apm_add_hook(struct apmhook **list, struct apmhook *ah)
 316 {
 317         struct apmhook *p, *prev;
 318
 319         APM_DPRINT("Add hook \"%s\"\n", ah->ah_name);
 320
 321         crit_enter();
 322         if (ah == NULL)
 323                 panic("illegal apm_hook!");
 324         prev = NULL;
 325         for (p = *list; p != NULL; prev = p, p = p->ah_next)
 326                 if (p->ah_order > ah->ah_order)
 327                         break;
 328
 329         if (prev == NULL) {
 330                 ah->ah_next = *list;
 331                 *list = ah;
 332         } else {
 333                 ah->ah_next = prev->ah_next;
 334                 prev->ah_next = ah;
 335         }
 336         crit_exit();
 337         return ah;
 338 }
 339
 340 static void
 341 apm_del_hook(struct apmhook **list, struct apmhook *ah)
 342 {
 343         struct apmhook *p, *prev;
 344
 345         crit_enter();
 346         prev = NULL;
 347         for (p = *list; p != NULL; prev = p, p = p->ah_next)
 348                 if (p == ah)
 349                         goto deleteit;
 350         panic("Tried to delete unregistered apm_hook.");
 351         goto nosuchnode;
 352 deleteit:
 353         if (prev != NULL)
 354                 prev->ah_next = p->ah_next;
 355         else
 356                 *list = p->ah_next;
 357 nosuchnode:
 358         crit_exit();
 359 }
 360
 361
 362 /* APM driver calls some functions automatically */
 363 static void
 364 apm_execute_hook(struct apmhook *list)
 365 {
 366         struct apmhook *p;
 367
 368         for (p = list; p != NULL; p = p->ah_next) {
 369                 APM_DPRINT("Execute APM hook \"%s.\"\n", p->ah_name);
 370                 if ((*(p->ah_fun))(p->ah_arg))
 371                         kprintf("Warning: APM hook \"%s\" failed", p->ah_name);
 372         }
 373 }
 374
 375
 376 /* establish an apm hook */
 377 struct apmhook *
 378 apm_hook_establish(int apmh, struct apmhook *ah)
 379 {
 380         if (apmh < 0 || apmh >= NAPM_HOOK)
 381                 return NULL;
 382
 383         return apm_add_hook(&hook[apmh], ah);
 384 }
 385
 386 /* disestablish an apm hook */
 387 void
 388 apm_hook_disestablish(int apmh, struct apmhook *ah)
 389 {
 390         if (apmh < 0 || apmh >= NAPM_HOOK)
 391                 return;
 392
 393         apm_del_hook(&hook[apmh], ah);
 394 }
 395
 396
 397 static struct timeval suspend_time;
 398 static struct timeval diff_time;
 399
 400 static int
 401 apm_default_resume(void *arg)
 402 {
 403         u_int second, minute, hour;
 404         struct timeval resume_time, tmp_time;
 405
 406         /* modified for adjkerntz */
 407         crit_enter();
 408         timer_restore();                /* restore the all timers */
 409         inittodr(0);                    /* adjust time to RTC */
 410         microtime(&resume_time);
 411         getmicrotime(&tmp_time);
 412         timevaladd(&tmp_time, &diff_time);
 413
 414 #ifdef FIXME
 415         /* XXX THIS DOESN'T WORK!!! */
 416         time = tmp_time;
 417 #endif
 418
 419 #ifdef APM_FIXUP_CALLTODO
 420         /* Calculate the delta time suspended */
 421         timevalsub(&resume_time, &suspend_time);
 422         /* Fixup the calltodo list with the delta time. */
 423         adjust_timeout_calltodo(&resume_time);
 424 #endif /* APM_FIXUP_CALLTODOK */
 425         crit_exit();
 426 #ifndef APM_FIXUP_CALLTODO
 427         second = resume_time.tv_sec - suspend_time.tv_sec;
 428 #else /* APM_FIXUP_CALLTODO */
 429         /*
 430          * We've already calculated resume_time to be the delta between
 431          * the suspend and the resume.
 432          */
 433         second = resume_time.tv_sec;
 434 #endif /* APM_FIXUP_CALLTODO */
 435         hour = second / 3600;
 436         second %= 3600;
 437         minute = second / 60;
 438         second %= 60;
 439         log(LOG_NOTICE, "resumed from suspended mode (slept %02d:%02d:%02d)\n",
 440                 hour, minute, second);
 441         return 0;
 442 }
 443
 444 static int
 445 apm_default_suspend(void *arg)
 446 {
 447         crit_enter();
 448         microtime(&diff_time);
 449         inittodr(0);
 450         microtime(&suspend_time);
 451         timevalsub(&diff_time, &suspend_time);
 452         crit_exit();
 453         return 0;
 454 }
 455
 456 static int apm_record_event (struct apm_softc *, u_int);
 457 static void apm_processevent(void);
 458
 459 static u_int apm_op_inprog = 0;
 460
 461 static void
 462 apm_do_suspend(void)
 463 {
 464         struct apm_softc *sc = &apm_softc;
 465         int error;
 466
 467         if (!sc)
 468                 return;
 469
 470         apm_op_inprog = 0;
 471         sc->suspends = sc->suspend_countdown = 0;
 472
 473         if (sc->initialized) {
 474                 error = DEVICE_SUSPEND(root_bus);
 475                 if (error) {
 476                         DEVICE_RESUME(root_bus);
 477                 } else {
 478                         apm_execute_hook(hook[APM_HOOK_SUSPEND]);
 479                         if (apm_suspend_system(PMST_SUSPEND) == 0) {
 480                                 apm_processevent();
 481                         } else {
 482                                 /* Failure, 'resume' the system again */
 483                                 apm_execute_hook(hook[APM_HOOK_RESUME]);
 484                                 DEVICE_RESUME(root_bus);
 485                         }
 486                 }
 487         }
 488 }
 489
 490 static void
 491 apm_do_standby(void)
 492 {
 493         struct apm_softc *sc = &apm_softc;
 494
 495         if (!sc)
 496                 return;
 497
 498         apm_op_inprog = 0;
 499         sc->standbys = sc->standby_countdown = 0;
 500
 501         if (sc->initialized) {
 502                 /*
 503                  * As far as standby, we don't need to execute
 504                  * all of suspend hooks.
 505                  */
 506                 apm_default_suspend(&apm_softc);
 507                 if (apm_suspend_system(PMST_STANDBY) == 0)
 508                         apm_processevent();
 509         }
 510 }
 511
 512 static void
 513 apm_lastreq_notify(void)
 514 {
 515         struct apm_softc *sc = &apm_softc;
 516
 517         sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
 518         sc->bios.r.ebx = PMDV_ALLDEV;
 519         sc->bios.r.ecx = PMST_LASTREQNOTIFY;
 520         sc->bios.r.edx = 0;
 521         apm_bioscall();
 522 }
 523
 524 static int
 525 apm_lastreq_rejected(void)
 526 {
 527         struct apm_softc *sc = &apm_softc;
 528
 529         if (apm_op_inprog == 0) {
 530                 return 1;       /* no operation in progress */
 531         }
 532
 533         sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
 534         sc->bios.r.ebx = PMDV_ALLDEV;
 535         sc->bios.r.ecx = PMST_LASTREQREJECT;
 536         sc->bios.r.edx = 0;
 537
 538         if (apm_bioscall()) {
 539                 APM_DPRINT("apm_lastreq_rejected: failed\n");
 540                 return 1;
 541         }
 542         apm_op_inprog = 0;
 543         return 0;
 544 }
 545
 546 /*
 547  * Public interface to the suspend/resume:
 548  *
 549  * Execute suspend and resume hook before and after sleep, respectively.
 550  *
 551  */
 552
 553 void
 554 apm_suspend(int state)
 555 {
 556         struct apm_softc *sc = &apm_softc;
 557
 558         if (!sc->initialized)
 559                 return;
 560
 561         switch (state) {
 562         case PMST_SUSPEND:
 563                 if (sc->suspends)
 564                         return;
 565                 sc->suspends++;
 566                 sc->suspend_countdown = apm_suspend_delay;
 567                 break;
 568         case PMST_STANDBY:
 569                 if (sc->standbys)
 570                         return;
 571                 sc->standbys++;
 572                 sc->standby_countdown = apm_standby_delay;
 573                 break;
 574         default:
 575                 kprintf("apm_suspend: Unknown Suspend state 0x%x\n", state);
 576                 return;
 577         }
 578
 579         apm_op_inprog++;
 580         apm_lastreq_notify();
 581 }
 582
 583 void
 584 apm_resume(void)
 585 {
 586         struct apm_softc *sc = &apm_softc;
 587
 588         if (!sc)
 589                 return;
 590
 591         if (sc->initialized) {
 592                 apm_execute_hook(hook[APM_HOOK_RESUME]);
 593                 DEVICE_RESUME(root_bus);
 594         }
 595 }
 596
 597
 598 /* get power status per battery */
 599 static int
 600 apm_get_pwstatus(apm_pwstatus_t app)
 601 {
 602         struct apm_softc *sc = &apm_softc;
 603
 604         if (app->ap_device != PMDV_ALLDEV &&
 605             (app->ap_device < PMDV_BATT0 || app->ap_device > PMDV_BATT_ALL))
 606                 return 1;
 607
 608         sc->bios.r.eax = (APM_BIOS << 8) | APM_GETPWSTATUS;
 609         sc->bios.r.ebx = app->ap_device;
 610         sc->bios.r.ecx = 0;
 611         sc->bios.r.edx = 0xffff;        /* default to unknown battery time */
 612
 613         if (apm_bioscall())
 614                 return 1;
 615
 616         app->ap_acline    = (sc->bios.r.ebx >> 8) & 0xff;
 617         app->ap_batt_stat = sc->bios.r.ebx & 0xff;
 618         app->ap_batt_flag = (sc->bios.r.ecx >> 8) & 0xff;
 619         app->ap_batt_life = sc->bios.r.ecx & 0xff;
 620         sc->bios.r.edx &= 0xffff;
 621         if (sc->bios.r.edx == 0xffff)   /* Time is unknown */
 622                 app->ap_batt_time = -1;
 623         else if (sc->bios.r.edx & 0x8000)       /* Time is in minutes */
 624                 app->ap_batt_time = (sc->bios.r.edx & 0x7fff) * 60;
 625         else                            /* Time is in seconds */
 626                 app->ap_batt_time = sc->bios.r.edx;
 627
 628         return 0;
 629 }
 630
 631
 632 /* get APM information */
 633 static int
 634 apm_get_info(apm_info_t aip)
 635 {
 636         struct apm_softc *sc = &apm_softc;
 637         struct apm_pwstatus aps;
 638
 639         bzero(&aps, sizeof(aps));
 640         aps.ap_device = PMDV_ALLDEV;
 641         if (apm_get_pwstatus(&aps))
 642                 return 1;
 643
 644         aip->ai_infoversion = 1;
 645         aip->ai_acline      = aps.ap_acline;
 646         aip->ai_batt_stat   = aps.ap_batt_stat;
 647         aip->ai_batt_life   = aps.ap_batt_life;
 648         aip->ai_batt_time   = aps.ap_batt_time;
 649         aip->ai_major       = (u_int)sc->majorversion;
 650         aip->ai_minor       = (u_int)sc->minorversion;
 651         aip->ai_status      = (u_int)sc->active;
 652
 653         sc->bios.r.eax = (APM_BIOS << 8) | APM_GETCAPABILITIES;
 654         sc->bios.r.ebx = 0;
 655         sc->bios.r.ecx = 0;
 656         sc->bios.r.edx = 0;
 657         if (apm_bioscall()) {
 658                 aip->ai_batteries = -1; /* Unknown */
 659                 aip->ai_capabilities = 0xff00; /* Unknown, with no bits set */
 660         } else {
 661                 aip->ai_batteries = sc->bios.r.ebx & 0xff;
 662                 aip->ai_capabilities = sc->bios.r.ecx & 0xf;
 663         }
 664
 665         bzero(aip->ai_spare, sizeof aip->ai_spare);
 666
 667         return 0;
 668 }
 669
 670
 671 /* inform APM BIOS that CPU is idle */
 672 void
 673 apm_cpu_idle(void)
 674 {
 675         struct apm_softc *sc = &apm_softc;
 676
 677         if (sc->active) {
 678
 679                 sc->bios.r.eax = (APM_BIOS <<8) | APM_CPUIDLE;
 680                 sc->bios.r.edx = sc->bios.r.ecx = sc->bios.r.ebx = 0;
 681                 apm_bioscall();
 682         }
 683         /*
 684          * Some APM implementation halts CPU in BIOS, whenever
 685          * "CPU-idle" function are invoked, but swtch() of
 686          * FreeBSD halts CPU, therefore, CPU is halted twice
 687          * in the sched loop. It makes the interrupt latency
 688          * terribly long and be able to cause a serious problem
 689          * in interrupt processing. We prevent it by removing
 690          * "hlt" operation from swtch() and managed it under
 691          * APM driver.
 692          */
 693         if (!sc->active || sc->always_halt_cpu)
 694                 __asm("hlt");   /* wait for interrupt */
 695 }
 696
 697 /* inform APM BIOS that CPU is busy */
 698 void
 699 apm_cpu_busy(void)
 700 {
 701         struct apm_softc *sc = &apm_softc;
 702
 703         /*
 704          * The APM specification says this is only necessary if your BIOS
 705          * slows down the processor in the idle task, otherwise it's not
 706          * necessary.
 707          */
 708         if (sc->slow_idle_cpu && sc->active) {
 709
 710                 sc->bios.r.eax = (APM_BIOS <<8) | APM_CPUBUSY;
 711                 sc->bios.r.edx = sc->bios.r.ecx = sc->bios.r.ebx = 0;
 712                 apm_bioscall();
 713         }
 714 }
 715
 716
 717 /*
 718  * APM timeout routine:
 719  *
 720  * This routine is automatically called by timer once per second.
 721  */
 722
 723 static void
 724 apm_timeout(void *dummy)
 725 {
 726         struct apm_softc *sc = &apm_softc;
 727
 728         if (apm_op_inprog)
 729                 apm_lastreq_notify();
 730
 731         if (sc->standbys && sc->standby_countdown-- <= 0)
 732                 apm_do_standby();
 733
 734         if (sc->suspends && sc->suspend_countdown-- <= 0)
 735                 apm_do_suspend();
 736
 737         if (!sc->bios_busy)
 738                 apm_processevent();
 739
 740         if (sc->active == 1) {
 741                 /* Run slightly more oftan than 1 Hz */
 742                 callout_reset(&apm_timeout_ch, hz - 1, apm_timeout, NULL);
 743         }
 744 }
 745
 746 /* enable APM BIOS */
 747 static void
 748 apm_event_enable(void)
 749 {
 750         struct apm_softc *sc = &apm_softc;
 751
 752         APM_DPRINT("called apm_event_enable()\n");
 753         if (sc->initialized) {
 754                 sc->active = 1;
 755                 callout_init(&apm_timeout_ch);
 756                 apm_timeout(sc);
 757         }
 758 }
 759
 760 /* disable APM BIOS */
 761 static void
 762 apm_event_disable(void)
 763 {
 764         struct apm_softc *sc = &apm_softc;
 765
 766         APM_DPRINT("called apm_event_disable()\n");
 767         if (sc->initialized) {
 768                 callout_stop(&apm_timeout_ch);
 769                 sc->active = 0;
 770         }
 771 }
 772
 773 /* halt CPU in scheduling loop */
 774 static void
 775 apm_halt_cpu(void)
 776 {
 777         struct apm_softc *sc = &apm_softc;
 778
 779         if (sc->initialized)
 780                 sc->always_halt_cpu = 1;
 781 }
 782
 783 /* don't halt CPU in scheduling loop */
 784 static void
 785 apm_not_halt_cpu(void)
 786 {
 787         struct apm_softc *sc = &apm_softc;
 788
 789         if (sc->initialized)
 790                 sc->always_halt_cpu = 0;
 791 }
 792
 793 /* device driver definitions */
 794
 795 /*
 796  * probe for APM BIOS
 797  */
 798 static int
 799 apm_probe(device_t dev)
 800 {
 801 #define APM_KERNBASE    KERNBASE
 802         struct vm86frame        vmf;
 803         struct apm_softc        *sc = &apm_softc;
 804         int                     disabled, flags;
 805
 806         if (resource_int_value("apm", 0, "disabled", &disabled) == 0
 807             && disabled != 0)
 808                 return ENXIO;
 809
 810         device_set_desc(dev, "APM BIOS");
 811
 812         if ( device_get_unit(dev) > 0 ) {
 813                 kprintf("apm: Only one APM driver supported.\n");
 814                 return ENXIO;
 815         }
 816
 817         if (resource_int_value("apm", 0, "flags", &flags) != 0)
 818                 flags = 0;
 819
 820         bzero(&vmf, sizeof(struct vm86frame));          /* safety */
 821         bzero(&apm_softc, sizeof(apm_softc));
 822         vmf.vmf_ah = APM_BIOS;
 823         vmf.vmf_al = APM_INSTCHECK;
 824         vmf.vmf_bx = 0;
 825         if (vm86_intcall(APM_INT, &vmf))
 826                 return ENXIO;                   /* APM not found */
 827         if (vmf.vmf_bx != 0x504d) {
 828                 kprintf("apm: incorrect signature (0x%x)\n", vmf.vmf_bx);
 829                 return ENXIO;
 830         }
 831         if ((vmf.vmf_cx & (APM_32BIT_SUPPORT | APM_16BIT_SUPPORT)) == 0) {
 832                 kprintf("apm: protected mode connections are not supported\n");
 833                 return ENXIO;
 834         }
 835
 836         apm_version = vmf.vmf_ax;
 837         sc->slow_idle_cpu = ((vmf.vmf_cx & APM_CPUIDLE_SLOW) != 0);
 838         sc->disabled = ((vmf.vmf_cx & APM_DISABLED) != 0);
 839         sc->disengaged = ((vmf.vmf_cx & APM_DISENGAGED) != 0);
 840
 841         vmf.vmf_ah = APM_BIOS;
 842         vmf.vmf_al = APM_DISCONNECT;
 843         vmf.vmf_bx = 0;
 844         vm86_intcall(APM_INT, &vmf);            /* disconnect, just in case */
 845
 846         if ((vmf.vmf_cx & APM_32BIT_SUPPORT) != 0) {
 847                 vmf.vmf_ah = APM_BIOS;
 848                 vmf.vmf_al = APM_PROT32CONNECT;
 849                 vmf.vmf_bx = 0;
 850                 if (vm86_intcall(APM_INT, &vmf)) {
 851                         kprintf("apm: 32-bit connection error.\n");
 852                         return (ENXIO);
 853                 }
 854                 sc->bios.seg.code32.base = (vmf.vmf_ax << 4) + APM_KERNBASE;
 855                 sc->bios.seg.code32.limit = 0xffff;
 856                 sc->bios.seg.code16.base = (vmf.vmf_cx << 4) + APM_KERNBASE;
 857                 sc->bios.seg.code16.limit = 0xffff;
 858                 sc->bios.seg.data.base = (vmf.vmf_dx << 4) + APM_KERNBASE;
 859                 sc->bios.seg.data.limit = 0xffff;
 860                 sc->bios.entry = vmf.vmf_ebx;
 861                 sc->connectmode = APM_PROT32CONNECT;
 862         } else {
 863                 /* use 16-bit connection */
 864                 vmf.vmf_ah = APM_BIOS;
 865                 vmf.vmf_al = APM_PROT16CONNECT;
 866                 vmf.vmf_bx = 0;
 867                 if (vm86_intcall(APM_INT, &vmf)) {
 868                         kprintf("apm: 16-bit connection error.\n");
 869                         return (ENXIO);
 870                 }
 871                 sc->bios.seg.code16.base = (vmf.vmf_ax << 4) + APM_KERNBASE;
 872                 sc->bios.seg.code16.limit = 0xffff;
 873                 sc->bios.seg.data.base = (vmf.vmf_cx << 4) + APM_KERNBASE;
 874                 sc->bios.seg.data.limit = 0xffff;
 875                 sc->bios.entry = vmf.vmf_bx;
 876                 sc->connectmode = APM_PROT16CONNECT;
 877         }
 878         return(0);
 879 }
 880
 881
 882 /*
 883  * return 0 if the user will notice and handle the event,
 884  * return 1 if the kernel driver should do so.
 885  */
 886 static int
 887 apm_record_event(struct apm_softc *sc, u_int event_type)
 888 {
 889         struct apm_event_info *evp;
 890
 891         if ((sc->sc_flags & SCFLAG_OPEN) == 0)
 892                 return 1;               /* no user waiting */
 893         if (sc->event_count == APM_NEVENTS)
 894                 return 1;                       /* overflow */
 895         if (sc->event_filter[event_type] == 0)
 896                 return 1;               /* not registered */
 897         evp = &sc->event_list[sc->event_ptr];
 898         sc->event_count++;
 899         sc->event_ptr++;
 900         sc->event_ptr %= APM_NEVENTS;
 901         evp->type = event_type;
 902         evp->index = ++apm_evindex;
 903         selwakeup(&sc->sc_rsel);
 904         return (sc->sc_flags & SCFLAG_OCTL) ? 0 : 1; /* user may handle */
 905 }
 906
 907 /* Process APM event */
 908 static void
 909 apm_processevent(void)
 910 {
 911         int apm_event;
 912         struct apm_softc *sc = &apm_softc;
 913
 914 #define OPMEV_DEBUGMESSAGE(symbol) case symbol:                         \
 915         APM_DPRINT("Received APM Event: " #symbol "\n");
 916
 917         do {
 918                 apm_event = apm_getevent();
 919                 switch (apm_event) {
 920                     OPMEV_DEBUGMESSAGE(PMEV_STANDBYREQ);
 921                         if (apm_op_inprog == 0) {
 922                             apm_op_inprog++;
 923                             if (apm_record_event(sc, apm_event)) {
 924                                 apm_suspend(PMST_STANDBY);
 925                             }
 926                         }
 927                         break;
 928                     OPMEV_DEBUGMESSAGE(PMEV_USERSTANDBYREQ);
 929                         if (apm_op_inprog == 0) {
 930                             apm_op_inprog++;
 931                             if (apm_record_event(sc, apm_event)) {
 932                                 apm_suspend(PMST_STANDBY);
 933                             }
 934                         }
 935                         break;
 936                     OPMEV_DEBUGMESSAGE(PMEV_SUSPENDREQ);
 937                         apm_lastreq_notify();
 938                         if (apm_op_inprog == 0) {
 939                             apm_op_inprog++;
 940                             if (apm_record_event(sc, apm_event)) {
 941                                 apm_do_suspend();
 942                             }
 943                         }
 944                         return; /* XXX skip the rest */
 945                     OPMEV_DEBUGMESSAGE(PMEV_USERSUSPENDREQ);
 946                         apm_lastreq_notify();
 947                         if (apm_op_inprog == 0) {
 948                             apm_op_inprog++;
 949                             if (apm_record_event(sc, apm_event)) {
 950                                 apm_do_suspend();
 951                             }
 952                         }
 953                         return; /* XXX skip the rest */
 954                     OPMEV_DEBUGMESSAGE(PMEV_CRITSUSPEND);
 955                         apm_do_suspend();
 956                         break;
 957                     OPMEV_DEBUGMESSAGE(PMEV_NORMRESUME);
 958                         apm_record_event(sc, apm_event);
 959                         apm_resume();
 960                         break;
 961                     OPMEV_DEBUGMESSAGE(PMEV_CRITRESUME);
 962                         apm_record_event(sc, apm_event);
 963                         apm_resume();
 964                         break;
 965                     OPMEV_DEBUGMESSAGE(PMEV_STANDBYRESUME);
 966                         apm_record_event(sc, apm_event);
 967                         apm_resume();
 968                         break;
 969                     OPMEV_DEBUGMESSAGE(PMEV_BATTERYLOW);
 970                         if (apm_record_event(sc, apm_event)) {
 971                             apm_battery_low();
 972                             apm_suspend(PMST_SUSPEND);
 973                         }
 974                         break;
 975                     OPMEV_DEBUGMESSAGE(PMEV_POWERSTATECHANGE);
 976                         apm_record_event(sc, apm_event);
 977                         break;
 978                     OPMEV_DEBUGMESSAGE(PMEV_UPDATETIME);
 979                         apm_record_event(sc, apm_event);
 980                         inittodr(0);    /* adjust time to RTC */
 981                         break;
 982                     OPMEV_DEBUGMESSAGE(PMEV_CAPABILITIESCHANGE);
 983                         apm_record_event(sc, apm_event);
 984                         break;
 985                     case PMEV_NOEVENT:
 986                         break;
 987                     default:
 988                         kprintf("Unknown Original APM Event 0x%x\n", apm_event);
 989                             break;
 990                 }
 991         } while (apm_event != PMEV_NOEVENT);
 992 }
 993
 994 /*
 995  * Attach APM:
 996  *
 997  * Initialize APM driver
 998  */
 999
1000 static int
1001 apm_attach(device_t dev)
1002 {
1003         struct apm_softc        *sc = &apm_softc;
1004         int                     flags;
1005         int                     drv_version;
1006
1007         if (resource_int_value("apm", 0, "flags", &flags) != 0)
1008                 flags = 0;
1009
1010         sc->initialized = 0;
1011
1012         /* Must be externally enabled */
1013         sc->active = 0;
1014
1015         /* Always call HLT in idle loop */
1016         sc->always_halt_cpu = 1;
1017
1018         kgetenv_int("debug.apm_debug", &apm_debug);
1019
1020         /* print bootstrap messages */
1021         APM_DPRINT("apm: APM BIOS version %04lx\n",  apm_version);
1022         APM_DPRINT("apm: Code16 0x%08x, Data 0x%08x\n",
1023             sc->bios.seg.code16.base, sc->bios.seg.data.base);
1024         APM_DPRINT("apm: Code entry 0x%08x, Idling CPU %s, Management %s\n",
1025             sc->bios.entry, is_enabled(sc->slow_idle_cpu),
1026             is_enabled(!sc->disabled));
1027         APM_DPRINT("apm: CS_limit=0x%x, DS_limit=0x%x\n",
1028             sc->bios.seg.code16.limit, sc->bios.seg.data.limit);
1029
1030         /*
1031          * In one test, apm bios version was 1.02; an attempt to register
1032          * a 1.04 driver resulted in a 1.00 connection!  Registering a
1033          * 1.02 driver resulted in a 1.02 connection.
1034          */
1035         drv_version = apm_version > 0x102 ? 0x102 : apm_version;
1036         for (; drv_version > 0x100; drv_version--)
1037                 if (apm_driver_version(drv_version) == 0)
1038                         break;
1039         sc->minorversion = ((drv_version & 0x00f0) >>  4) * 10 +
1040                 ((drv_version & 0x000f) >> 0);
1041         sc->majorversion = ((drv_version & 0xf000) >> 12) * 10 +
1042                 ((apm_version & 0x0f00) >> 8);
1043
1044         sc->intversion = INTVERSION(sc->majorversion, sc->minorversion);
1045
1046         if (sc->intversion >= INTVERSION(1, 1))
1047                 APM_DPRINT("apm: Engaged control %s\n", is_enabled(!sc->disengaged));
1048         device_printf(dev, "found APM BIOS v%ld.%ld, connected at v%d.%d\n",
1049                ((apm_version & 0xf000) >> 12) * 10 + ((apm_version & 0x0f00) >> 8),
1050                ((apm_version & 0x00f0) >> 4) * 10 + ((apm_version & 0x000f) >> 0),
1051                sc->majorversion, sc->minorversion);
1052
1053
1054         APM_DPRINT("apm: Slow Idling CPU %s\n", is_enabled(sc->slow_idle_cpu));
1055         /* enable power management */
1056         if (sc->disabled) {
1057                 if (apm_enable_disable_pm(1)) {
1058                         APM_DPRINT("apm: *Warning* enable function failed! [%x]\n",
1059                             (sc->bios.r.eax >> 8) & 0xff);
1060                 }
1061         }
1062
1063         /* engage power managment (APM 1.1 or later) */
1064         if (sc->intversion >= INTVERSION(1, 1) && sc->disengaged) {
1065                 if (apm_engage_disengage_pm(1)) {
1066                         APM_DPRINT("apm: *Warning* engage function failed err=[%x]",
1067                             (sc->bios.r.eax >> 8) & 0xff);
1068                         APM_DPRINT(" (Docked or using external power?).\n");
1069                 }
1070         }
1071
1072         /* default suspend hook */
1073         sc->sc_suspend.ah_fun = apm_default_suspend;
1074         sc->sc_suspend.ah_arg = sc;
1075         sc->sc_suspend.ah_name = "default suspend";
1076         sc->sc_suspend.ah_order = APM_MAX_ORDER;
1077
1078         /* default resume hook */
1079         sc->sc_resume.ah_fun = apm_default_resume;
1080         sc->sc_resume.ah_arg = sc;
1081         sc->sc_resume.ah_name = "default resume";
1082         sc->sc_resume.ah_order = APM_MIN_ORDER;
1083
1084         apm_hook_establish(APM_HOOK_SUSPEND, &sc->sc_suspend);
1085         apm_hook_establish(APM_HOOK_RESUME , &sc->sc_resume);
1086
1087         /* Power the system off using APM */
1088         EVENTHANDLER_REGISTER(shutdown_final, apm_power_off, NULL,
1089                               SHUTDOWN_PRI_LAST);
1090
1091         sc->initialized = 1;
1092
1093         dev_ops_add(&apm_ops, 0, 0);
1094         make_dev(&apm_ops, 0, UID_ROOT, GID_OPERATOR, 0660, "apm");
1095         make_dev(&apm_ops, 8, UID_ROOT, GID_OPERATOR, 0660, "apmctl");
1096         return 0;
1097 }
1098
1099 static int
1100 apmopen(struct dev_open_args *ap)
1101 {
1102         cdev_t dev = ap->a_head.a_dev;
1103         struct apm_softc *sc = &apm_softc;
1104         int ctl = APMDEV(dev);
1105
1106         if (!sc->initialized)
1107                 return (ENXIO);
1108
1109         switch (ctl) {
1110         case APMDEV_CTL:
1111                 if (!(ap->a_oflags & FWRITE))
1112                         return EINVAL;
1113                 if (sc->sc_flags & SCFLAG_OCTL)
1114                         return EBUSY;
1115                 sc->sc_flags |= SCFLAG_OCTL;
1116                 bzero(sc->event_filter, sizeof sc->event_filter);
1117                 break;
1118         case APMDEV_NORMAL:
1119                 sc->sc_flags |= SCFLAG_ONORMAL;
1120                 break;
1121         default:
1122                 return ENXIO;
1123                 break;
1124         }
1125         return 0;
1126 }
1127
1128 static int
1129 apmclose(struct dev_close_args *ap)
1130 {
1131         cdev_t dev = ap->a_head.a_dev;
1132         struct apm_softc *sc = &apm_softc;
1133         int ctl = APMDEV(dev);
1134
1135         switch (ctl) {
1136         case APMDEV_CTL:
1137                 apm_lastreq_rejected();
1138                 sc->sc_flags &= ~SCFLAG_OCTL;
1139                 bzero(sc->event_filter, sizeof sc->event_filter);
1140                 break;
1141         case APMDEV_NORMAL:
1142                 sc->sc_flags &= ~SCFLAG_ONORMAL;
1143                 break;
1144         }
1145         if ((sc->sc_flags & SCFLAG_OPEN) == 0) {
1146                 sc->event_count = 0;
1147                 sc->event_ptr = 0;
1148         }
1149         return 0;
1150 }
1151
1152 static int
1153 apmioctl(struct dev_ioctl_args *ap)
1154 {
1155         cdev_t dev = ap->a_head.a_dev;
1156         struct apm_softc *sc = &apm_softc;
1157         struct apm_bios_arg *args;
1158         int error = 0;
1159         int ret;
1160         int newstate;
1161
1162         if (!sc->initialized)
1163                 return (ENXIO);
1164         APM_DPRINT("APM ioctl: cmd = 0x%lx\n", ap->a_cmd);
1165
1166         switch (ap->a_cmd) {
1167         case APMIO_SUSPEND:
1168                 if (!(ap->a_fflag & FWRITE))
1169                         return (EPERM);
1170                 if (sc->active)
1171                         apm_suspend(PMST_SUSPEND);
1172                 else
1173                         error = EINVAL;
1174                 break;
1175
1176         case APMIO_STANDBY:
1177                 if (!(ap->a_fflag & FWRITE))
1178                         return (EPERM);
1179                 if (sc->active)
1180                         apm_suspend(PMST_STANDBY);
1181                 else
1182                         error = EINVAL;
1183                 break;
1184
1185         case APMIO_GETINFO_OLD:
1186                 {
1187                         struct apm_info info;
1188                         apm_info_old_t aiop;
1189
1190                         if (apm_get_info(&info))
1191                                 error = ENXIO;
1192                         aiop = (apm_info_old_t)ap->a_data;
1193                         aiop->ai_major = info.ai_major;
1194                         aiop->ai_minor = info.ai_minor;
1195                         aiop->ai_acline = info.ai_acline;
1196                         aiop->ai_batt_stat = info.ai_batt_stat;
1197                         aiop->ai_batt_life = info.ai_batt_life;
1198                         aiop->ai_status = info.ai_status;
1199                 }
1200                 break;
1201         case APMIO_GETINFO:
1202                 if (apm_get_info((apm_info_t)ap->a_data))
1203                         error = ENXIO;
1204                 break;
1205         case APMIO_GETPWSTATUS:
1206                 if (apm_get_pwstatus((apm_pwstatus_t)ap->a_data))
1207                         error = ENXIO;
1208                 break;
1209         case APMIO_ENABLE:
1210                 if (!(ap->a_fflag & FWRITE))
1211                         return (EPERM);
1212                 apm_event_enable();
1213                 break;
1214         case APMIO_DISABLE:
1215                 if (!(ap->a_fflag & FWRITE))
1216                         return (EPERM);
1217                 apm_event_disable();
1218                 break;
1219         case APMIO_HALTCPU:
1220                 if (!(ap->a_fflag & FWRITE))
1221                         return (EPERM);
1222                 apm_halt_cpu();
1223                 break;
1224         case APMIO_NOTHALTCPU:
1225                 if (!(ap->a_fflag & FWRITE))
1226                         return (EPERM);
1227                 apm_not_halt_cpu();
1228                 break;
1229         case APMIO_DISPLAY:
1230                 if (!(ap->a_fflag & FWRITE))
1231                         return (EPERM);
1232                 newstate = *(int *)ap->a_data;
1233                 if (apm_display(newstate))
1234                         error = ENXIO;
1235                 break;
1236         case APMIO_BIOS:
1237                 if (!(ap->a_fflag & FWRITE))
1238                         return (EPERM);
1239                 /* XXX compatibility with the old interface */
1240                 args = (struct apm_bios_arg *)ap->a_data;
1241                 sc->bios.r.eax = args->eax;
1242                 sc->bios.r.ebx = args->ebx;
1243                 sc->bios.r.ecx = args->ecx;
1244                 sc->bios.r.edx = args->edx;
1245                 sc->bios.r.esi = args->esi;
1246                 sc->bios.r.edi = args->edi;
1247                 if ((ret = apm_bioscall())) {
1248                         /*
1249                          * Return code 1 means bios call was unsuccessful.
1250                          * Error code is stored in %ah.
1251                          * Return code -1 means bios call was unsupported
1252                          * in the APM BIOS version.
1253                          */
1254                         if (ret == -1) {
1255                                 error = EINVAL;
1256                         }
1257                 } else {
1258                         /*
1259                          * Return code 0 means bios call was successful.
1260                          * We need only %al and can discard %ah.
1261                          */
1262                         sc->bios.r.eax &= 0xff;
1263                 }
1264                 args->eax = sc->bios.r.eax;
1265                 args->ebx = sc->bios.r.ebx;
1266                 args->ecx = sc->bios.r.ecx;
1267                 args->edx = sc->bios.r.edx;
1268                 args->esi = sc->bios.r.esi;
1269                 args->edi = sc->bios.r.edi;
1270                 break;
1271         default:
1272                 error = EINVAL;
1273                 break;
1274         }
1275
1276         /* for /dev/apmctl */
1277         if (APMDEV(dev) == APMDEV_CTL) {
1278                 struct apm_event_info *evp;
1279                 int i;
1280
1281                 error = 0;
1282                 switch (ap->a_cmd) {
1283                 case APMIO_NEXTEVENT:
1284                         if (!sc->event_count) {
1285                                 error = EAGAIN;
1286                         } else {
1287                                 evp = (struct apm_event_info *)ap->a_data;
1288                                 i = sc->event_ptr + APM_NEVENTS - sc->event_count;
1289                                 i %= APM_NEVENTS;
1290                                 *evp = sc->event_list[i];
1291                                 sc->event_count--;
1292                         }
1293                         break;
1294                 case APMIO_REJECTLASTREQ:
1295                         if (apm_lastreq_rejected()) {
1296                                 error = EINVAL;
1297                         }
1298                         break;
1299                 default:
1300                         error = EINVAL;
1301                         break;
1302                 }
1303         }
1304
1305         return error;
1306 }
1307
1308 static int
1309 apmwrite(struct dev_write_args *ap)
1310 {
1311         cdev_t dev = ap->a_head.a_dev;
1312         struct uio *uio = ap->a_uio;
1313         struct apm_softc *sc = &apm_softc;
1314         u_int event_type;
1315         int error;
1316         u_char enabled;
1317
1318         if (APMDEV(dev) != APMDEV_CTL)
1319                 return(ENODEV);
1320         if (uio->uio_resid != sizeof(u_int))
1321                 return(E2BIG);
1322
1323         if ((error = uiomove((caddr_t)&event_type, sizeof(u_int), uio)))
1324                 return(error);
1325
1326         if (event_type < 0 || event_type >= APM_NPMEV)
1327                 return(EINVAL);
1328
1329         if (sc->event_filter[event_type] == 0) {
1330                 enabled = 1;
1331         } else {
1332                 enabled = 0;
1333         }
1334         sc->event_filter[event_type] = enabled;
1335         APM_DPRINT("apmwrite: event 0x%x %s\n", event_type, is_enabled(enabled));
1336
1337         return uio->uio_resid;
1338 }
1339
1340 static int
1341 apmpoll(struct dev_poll_args *ap)
1342 {
1343         struct apm_softc *sc = &apm_softc;
1344         int revents = 0;
1345
1346         if (ap->a_events & (POLLIN | POLLRDNORM)) {
1347                 if (sc->event_count) {
1348                         revents |= ap->a_events & (POLLIN | POLLRDNORM);
1349                 } else {
1350                         selrecord(curthread, &sc->sc_rsel);
1351                 }
1352         }
1353         ap->a_events = revents;
1354         return (0);
1355 }
1356
1357 /*
1358  * Because apm is a static device that always exists under any attached
1359  * isa device, and not scanned by the isa device, we need an identify
1360  * function to install the device so we can probe for it.
1361  */
1362 static device_method_t apm_methods[] = {
1363         /* Device interface */
1364         DEVMETHOD(device_identify,      bus_generic_identify),
1365         DEVMETHOD(device_probe,         apm_probe),
1366         DEVMETHOD(device_attach,        apm_attach),
1367
1368         { 0, 0 }
1369 };
1370
1371 static driver_t apm_driver = {
1372         "apm",
1373         apm_methods,
1374         1,                      /* no softc (XXX) */
1375 };
1376
1377 static devclass_t apm_devclass;
1378
1379 DRIVER_MODULE(apm, nexus, apm_driver, apm_devclass, 0, 0);
1380