acpi_powerres.c revision 82084
1/*- 2 * Copyright (c) 2001 Michael Smith 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/dev/acpica/acpi_powerres.c 82084 2001-08-21 18:22:40Z iwasaki $ 27 */ 28 29#include "opt_acpi.h" /* XXX trim includes */ 30#include <sys/param.h> 31#include <sys/kernel.h> 32#include <sys/proc.h> 33#include <sys/lock.h> 34#include <sys/malloc.h> 35#include <sys/mutex.h> 36#include <sys/bus.h> 37#include <sys/conf.h> 38#include <sys/ioccom.h> 39#include <sys/reboot.h> 40#include <sys/sysctl.h> 41#include <sys/systm.h> 42#include <sys/ctype.h> 43 44#include <machine/clock.h> 45 46#include <machine/resource.h> 47 48#include "acpi.h" 49 50#include <dev/acpica/acpivar.h> 51#include <dev/acpica/acpiio.h> 52 53/* 54 * ACPI power resource management. 55 * 56 * Power resource behaviour is slightly complicated by the fact that 57 * a single power resource may provide power for more than one device. 58 * Thus, we must track the device(s) being powered by a given power 59 * resource, and only deactivate it when there are no powered devices. 60 * 61 * Note that this only manages resources for known devices. There is an 62 * ugly case where we may turn of power to a device which is in use because 63 * we don't know that it depends on a given resource. We should perhaps 64 * try to be smarter about this, but a more complete solution would involve 65 * scanning all of the ACPI namespace to find devices we're not currently 66 * aware of, and this raises questions about whether they should be left 67 * on, turned off, etc. 68 * 69 * XXX locking 70 */ 71 72MALLOC_DEFINE(M_ACPIPWR, "acpipwr", "ACPI power resources"); 73 74/* 75 * Hooks for the ACPI CA debugging infrastructure 76 */ 77#define _COMPONENT ACPI_POWER 78MODULE_NAME("POWERRES") 79 80/* return values from _STA on a power resource */ 81#define ACPI_PWR_OFF 0 82#define ACPI_PWR_ON 1 83 84/* 85 * A relationship between a power resource and a consumer. 86 */ 87struct acpi_powerreference { 88 struct acpi_powerconsumer *ar_consumer; 89 struct acpi_powerresource *ar_resource; 90 TAILQ_ENTRY(acpi_powerreference) ar_rlink; /* link on resource list */ 91 TAILQ_ENTRY(acpi_powerreference) ar_clink; /* link on consumer */ 92}; 93 94/* 95 * A power-managed device. 96 */ 97struct acpi_powerconsumer { 98 ACPI_HANDLE ac_consumer; /* device which is powered */ 99 int ac_state; 100 TAILQ_ENTRY(acpi_powerconsumer) ac_link; 101 TAILQ_HEAD(,acpi_powerreference) ac_references; 102}; 103 104/* 105 * A power resource. 106 */ 107struct acpi_powerresource { 108 TAILQ_ENTRY(acpi_powerresource) ap_link; 109 TAILQ_HEAD(,acpi_powerreference) ap_references; 110 ACPI_HANDLE ap_resource; /* the resource's handle */ 111 ACPI_INTEGER ap_systemlevel; 112 ACPI_INTEGER ap_order; 113}; 114 115TAILQ_HEAD(acpi_powerresource_list, acpi_powerresource) acpi_powerresources; 116TAILQ_HEAD(acpi_powerconsumer_list, acpi_powerconsumer) acpi_powerconsumers; 117 118static ACPI_STATUS acpi_pwr_register_consumer(ACPI_HANDLE consumer); 119static ACPI_STATUS acpi_pwr_deregister_consumer(ACPI_HANDLE consumer); 120static ACPI_STATUS acpi_pwr_register_resource(ACPI_HANDLE res); 121static ACPI_STATUS acpi_pwr_deregister_resource(ACPI_HANDLE res); 122static void acpi_pwr_reference_resource(ACPI_OBJECT *obj, void *arg); 123static ACPI_STATUS acpi_pwr_switch_power(void); 124static struct acpi_powerresource *acpi_pwr_find_resource(ACPI_HANDLE res); 125static struct acpi_powerconsumer *acpi_pwr_find_consumer(ACPI_HANDLE consumer); 126 127/* 128 * Initialise our lists. 129 */ 130static void 131acpi_pwr_init(void *junk) 132{ 133 TAILQ_INIT(&acpi_powerresources); 134 TAILQ_INIT(&acpi_powerconsumers); 135} 136SYSINIT(acpi_powerresource, SI_SUB_TUNABLES, SI_ORDER_ANY, acpi_pwr_init, NULL); 137 138/* 139 * Register a power resource. 140 * 141 * It's OK to call this if we already know about the resource. 142 */ 143static ACPI_STATUS 144acpi_pwr_register_resource(ACPI_HANDLE res) 145{ 146 ACPI_STATUS status; 147 ACPI_BUFFER buf; 148 ACPI_OBJECT *obj; 149 struct acpi_powerresource *rp, *srp; 150 151 FUNCTION_TRACE(__func__); 152 153 rp = NULL; 154 obj = NULL; 155 156 /* look to see if we know about this resource */ 157 if (acpi_pwr_find_resource(res) != NULL) 158 return_ACPI_STATUS(AE_OK); /* already know about it */ 159 160 /* allocate a new resource */ 161 if ((rp = malloc(sizeof(*rp), M_ACPIPWR, M_NOWAIT | M_ZERO)) == NULL) { 162 status = AE_NO_MEMORY; 163 goto out; 164 } 165 TAILQ_INIT(&rp->ap_references); 166 rp->ap_resource = res; 167 168 /* get the Power Resource object */ 169 if ((status = acpi_EvaluateIntoBuffer(res, NULL, NULL, &buf)) != AE_OK) { 170 DEBUG_PRINT(TRACE_OBJECTS, ("no power resource object\n")); 171 goto out; 172 } 173 obj = buf.Pointer; 174 if (obj->Type != ACPI_TYPE_POWER) { 175 DEBUG_PRINT(TRACE_OBJECTS, ("questionable power resource object %s\n", acpi_name(res))); 176 status = AE_TYPE; 177 goto out; 178 } 179 rp->ap_systemlevel = obj->PowerResource.SystemLevel; 180 rp->ap_order = obj->PowerResource.ResourceOrder; 181 182 /* sort the resource into the list */ 183 status = AE_OK; 184 srp = TAILQ_FIRST(&acpi_powerresources); 185 if ((srp == NULL) || (rp->ap_order < srp->ap_order)) { 186 TAILQ_INSERT_HEAD(&acpi_powerresources, rp, ap_link); 187 goto done; 188 } 189 TAILQ_FOREACH(srp, &acpi_powerresources, ap_link) 190 if (rp->ap_order < srp->ap_order) { 191 TAILQ_INSERT_BEFORE(srp, rp, ap_link); 192 goto done; 193 } 194 TAILQ_INSERT_TAIL(&acpi_powerresources, rp, ap_link); 195 196 done: 197 DEBUG_PRINT(TRACE_OBJECTS, ("registered power resource %s\n", acpi_name(res))); 198 out: 199 if (obj != NULL) 200 AcpiOsFree(obj); 201 if ((status != AE_OK) && (rp != NULL)) 202 free(rp, M_ACPIPWR); 203 return_ACPI_STATUS(status); 204} 205 206/* 207 * Deregister a power resource. 208 */ 209static ACPI_STATUS 210acpi_pwr_deregister_resource(ACPI_HANDLE res) 211{ 212 struct acpi_powerresource *rp; 213 214 FUNCTION_TRACE(__func__); 215 216 rp = NULL; 217 218 /* find the resource */ 219 if ((rp = acpi_pwr_find_resource(res)) == NULL) 220 return_ACPI_STATUS(AE_BAD_PARAMETER); 221 222 /* check that there are no consumers referencing this resource */ 223 if (TAILQ_FIRST(&rp->ap_references) != NULL) 224 return_ACPI_STATUS(AE_BAD_PARAMETER); 225 226 /* pull it off the list and free it */ 227 TAILQ_REMOVE(&acpi_powerresources, rp, ap_link); 228 free(rp, M_ACPIPWR); 229 230 DEBUG_PRINT(TRACE_OBJECTS, ("deregistered power resource %s\n", acpi_name(res))); 231 232 return_ACPI_STATUS(AE_OK); 233} 234 235/* 236 * Register a power consumer. 237 * 238 * It's OK to call this if we already know about the consumer. 239 */ 240static ACPI_STATUS 241acpi_pwr_register_consumer(ACPI_HANDLE consumer) 242{ 243 struct acpi_powerconsumer *pc; 244 245 FUNCTION_TRACE(__func__); 246 247 /* check to see whether we know about this consumer already */ 248 if ((pc = acpi_pwr_find_consumer(consumer)) != NULL) 249 return_ACPI_STATUS(AE_OK); 250 251 /* allocate a new power consumer */ 252 if ((pc = malloc(sizeof(*pc), M_ACPIPWR, M_NOWAIT)) == NULL) 253 return_ACPI_STATUS(AE_NO_MEMORY); 254 TAILQ_INSERT_HEAD(&acpi_powerconsumers, pc, ac_link); 255 TAILQ_INIT(&pc->ac_references); 256 pc->ac_consumer = consumer; 257 258 pc->ac_state = ACPI_STATE_UNKNOWN; /* XXX we should try to find its current state */ 259 260 DEBUG_PRINT(TRACE_OBJECTS, ("registered power consumer %s\n", acpi_name(consumer))); 261 262 return_ACPI_STATUS(AE_OK); 263} 264 265/* 266 * Deregister a power consumer. 267 * 268 * This should only be done once the consumer has been powered off. 269 * (XXX is this correct? Check once implemented) 270 */ 271static ACPI_STATUS 272acpi_pwr_deregister_consumer(ACPI_HANDLE consumer) 273{ 274 struct acpi_powerconsumer *pc; 275 276 FUNCTION_TRACE(__func__); 277 278 /* find the consumer */ 279 if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) 280 return_ACPI_STATUS(AE_BAD_PARAMETER); 281 282 /* make sure the consumer's not referencing anything right now */ 283 if (TAILQ_FIRST(&pc->ac_references) != NULL) 284 return_ACPI_STATUS(AE_BAD_PARAMETER); 285 286 /* pull the consumer off the list and free it */ 287 TAILQ_REMOVE(&acpi_powerconsumers, pc, ac_link); 288 289 DEBUG_PRINT(TRACE_OBJECTS, ("deregistered power consumer %s\n", acpi_name(consumer))); 290 291 return_ACPI_STATUS(AE_OK); 292} 293 294/* 295 * Set a power consumer to a particular power state. 296 */ 297ACPI_STATUS 298acpi_pwr_switch_consumer(ACPI_HANDLE consumer, int state) 299{ 300 struct acpi_powerconsumer *pc; 301 struct acpi_powerreference *pr; 302 ACPI_HANDLE method_handle, reslist_handle, pr0_handle; 303 ACPI_BUFFER reslist_buffer; 304 ACPI_OBJECT *reslist_object; 305 ACPI_STATUS status; 306 char *method_name, *reslist_name; 307 int res_changed; 308 309 FUNCTION_TRACE(__func__); 310 311 /* find the consumer */ 312 if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) { 313 if ((status = acpi_pwr_register_consumer(consumer)) != AE_OK) 314 return_ACPI_STATUS(status); 315 if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) { 316 return_ACPI_STATUS(AE_ERROR); /* something very wrong */ 317 } 318 } 319 320 /* check for valid transitions */ 321 if ((pc->ac_state == ACPI_STATE_D3) && (state != ACPI_STATE_D0)) 322 return_ACPI_STATUS(AE_BAD_PARAMETER); /* can only go to D0 from D3 */ 323 324 /* find transition mechanism(s) */ 325 switch(state) { 326 case ACPI_STATE_D0: 327 method_name = "_PS0"; 328 reslist_name = "_PR0"; 329 break; 330 case ACPI_STATE_D1: 331 method_name = "_PS1"; 332 reslist_name = "_PR1"; 333 break; 334 case ACPI_STATE_D2: 335 method_name = "_PS2"; 336 reslist_name = "_PR2"; 337 break; 338 case ACPI_STATE_D3: 339 method_name = "_PS3"; 340 reslist_name = "_PR3"; 341 break; 342 default: 343 return_ACPI_STATUS(AE_BAD_PARAMETER); 344 } 345 DEBUG_PRINT(TRACE_OBJECTS, ("setup to switch %s D%d -> D%d\n", 346 acpi_name(consumer), pc->ac_state, state)); 347 348 /* 349 * Verify that this state is supported, ie. one of method or 350 * reslist must be present. We need to do this before we go 351 * dereferencing resources (since we might be trying to go to 352 * a state we don't support). 353 * 354 * Note that if any states are supported, the device has to 355 * support D0 and D3. It's never an error to try to go to 356 * D0. 357 */ 358 reslist_object = NULL; 359 if (AcpiGetHandle(consumer, method_name, &method_handle) != AE_OK) 360 method_handle = NULL; 361 if (AcpiGetHandle(consumer, reslist_name, &reslist_handle) != AE_OK) 362 reslist_handle = NULL; 363 if ((reslist_handle == NULL) && (method_handle == NULL)) { 364 if (state == ACPI_STATE_D0) { 365 pc->ac_state = ACPI_STATE_D0; 366 return_ACPI_STATUS(AE_OK); 367 } 368 if (state != ACPI_STATE_D3) { 369 goto bad; 370 } 371 372 /* turn off the resources listed in _PR0 to go to D3. */ 373 if (AcpiGetHandle(consumer, "_PR0", &pr0_handle) != AE_OK) { 374 goto bad; 375 } 376 status = acpi_EvaluateIntoBuffer(pr0_handle, NULL, NULL, &reslist_buffer); 377 if (status != AE_OK) { 378 goto bad; 379 } 380 reslist_object = (ACPI_OBJECT *)reslist_buffer.Pointer; 381 if ((reslist_object->Type != ACPI_TYPE_PACKAGE) || 382 (reslist_object->Package.Count == 0)) { 383 goto bad; 384 } 385 AcpiOsFree(reslist_object); 386 } 387 388 /* 389 * Check that we can actually fetch the list of power resources 390 */ 391 if (reslist_handle != NULL) { 392 if ((status = acpi_EvaluateIntoBuffer(reslist_handle, NULL, NULL, &reslist_buffer)) != AE_OK) { 393 DEBUG_PRINT(TRACE_OBJECTS, ("can't evaluate resource list %s\n", 394 acpi_name(reslist_handle))); 395 return_ACPI_STATUS(status); 396 } 397 reslist_object = (ACPI_OBJECT *)reslist_buffer.Pointer; 398 if (reslist_object->Type != ACPI_TYPE_PACKAGE) { 399 DEBUG_PRINT(TRACE_OBJECTS, ("resource list is not ACPI_TYPE_PACKAGE (%d)\n", 400 reslist_object->Type)); 401 return_ACPI_STATUS(AE_TYPE); 402 } 403 } else { 404 reslist_object = NULL; 405 } 406 407 /* 408 * Now we are ready to switch, so kill off any current power resource references. 409 */ 410 res_changed = 0; 411 while((pr = TAILQ_FIRST(&pc->ac_references)) != NULL) { 412 res_changed = 1; 413 DEBUG_PRINT(TRACE_OBJECTS, ("removing reference to %s\n", acpi_name(pr->ar_resource->ap_resource))); 414 TAILQ_REMOVE(&pr->ar_resource->ap_references, pr, ar_rlink); 415 TAILQ_REMOVE(&pc->ac_references, pr, ar_clink); 416 free(pr, M_ACPIPWR); 417 } 418 419 /* 420 * Add new power resource references, if we have any. Traverse the 421 * package that we got from evaluating reslist_handle, and look up each 422 * of the resources that are referenced. 423 */ 424 if (reslist_object != NULL) { 425 DEBUG_PRINT(TRACE_OBJECTS, ("referencing %d new resources\n", 426 reslist_object->Package.Count)); 427 acpi_ForeachPackageObject(reslist_object, acpi_pwr_reference_resource, pc); 428 res_changed = 1; 429 } 430 431 /* 432 * If we changed anything in the resource list, we need to run a switch 433 * pass now. 434 */ 435 if ((status = acpi_pwr_switch_power()) != AE_OK) { 436 DEBUG_PRINT(TRACE_OBJECTS, ("failed to correctly switch resources to move %s to D%d\n", 437 acpi_name(consumer), state)); 438 return_ACPI_STATUS(status); /* XXX is this appropriate? Should we return to previous state? */ 439 } 440 441 /* invoke power state switch method (if present) */ 442 if (method_handle != NULL) { 443 DEBUG_PRINT(TRACE_OBJECTS, ("invoking state transition method %s\n", 444 acpi_name(method_handle))); 445 if ((status = AcpiEvaluateObject(method_handle, NULL, NULL, NULL)) != AE_OK) 446 pc->ac_state = ACPI_STATE_UNKNOWN; 447 return_ACPI_STATUS(status); /* XXX is this appropriate? Should we return to previous state? */ 448 } 449 450 /* transition was successful */ 451 pc->ac_state = state; 452 return_ACPI_STATUS(AE_OK); 453 454 bad: 455 DEBUG_PRINT(TRACE_OBJECTS, ("attempt to set unsupported state D%d\n", 456 state)); 457 if (reslist_object) 458 AcpiOsFree(reslist_object); 459 return_ACPI_STATUS(AE_BAD_PARAMETER); 460} 461 462/* 463 * Called to create a reference between a power consumer and a power resource 464 * identified in the object. 465 */ 466static void 467acpi_pwr_reference_resource(ACPI_OBJECT *obj, void *arg) 468{ 469 struct acpi_powerconsumer *pc = (struct acpi_powerconsumer *)arg; 470 struct acpi_powerreference *pr; 471 struct acpi_powerresource *rp; 472 ACPI_HANDLE res; 473 ACPI_STATUS status; 474 475 FUNCTION_TRACE(__func__); 476 477 /* check the object type */ 478 if (obj->Type != ACPI_TYPE_STRING) { 479 DEBUG_PRINT(TRACE_OBJECTS, ("don't know how to create a power reference to object type %d\n", 480 obj->Type)); 481 return_VOID; 482 } 483 484 DEBUG_PRINT(TRACE_OBJECTS, ("building reference from %s to %s\n", 485 acpi_name(pc->ac_consumer), obj->String.Pointer)); 486 487 /* get the handle of the resource */ 488 if (ACPI_FAILURE(status = AcpiGetHandle(NULL, obj->String.Pointer, &res))) { 489 DEBUG_PRINT(TRACE_OBJECTS, ("couldn't find power resource %s\n", 490 obj->String.Pointer)); 491 return_VOID; 492 } 493 494 /* create/look up the resource */ 495 if (ACPI_FAILURE(status = acpi_pwr_register_resource(res))) { 496 DEBUG_PRINT(TRACE_OBJECTS, ("couldn't register power resource %s - %s\n", 497 obj->String.Pointer, AcpiFormatException(status))); 498 return_VOID; 499 } 500 if ((rp = acpi_pwr_find_resource(res)) == NULL) { 501 DEBUG_PRINT(TRACE_OBJECTS, ("power resource list corrupted\n")); 502 return_VOID; 503 } 504 DEBUG_PRINT(TRACE_OBJECTS, ("found power resource %s\n", acpi_name(rp->ap_resource))); 505 506 /* create a reference between the consumer and resource */ 507 if ((pr = malloc(sizeof(*pr), M_ACPIPWR, M_NOWAIT | M_ZERO)) == NULL) { 508 DEBUG_PRINT(TRACE_OBJECTS, ("couldn't allocate memory for a power consumer reference\n")); 509 return_VOID; 510 } 511 pr->ar_consumer = pc; 512 pr->ar_resource = rp; 513 TAILQ_INSERT_TAIL(&pc->ac_references, pr, ar_clink); 514 TAILQ_INSERT_TAIL(&rp->ap_references, pr, ar_rlink); 515 516 return_VOID; 517} 518 519 520/* 521 * Switch power resources to conform to the desired state. 522 * 523 * Consumers may have modified the power resource list in an arbitrary 524 * fashion; we sweep it in sequence order. 525 */ 526static ACPI_STATUS 527acpi_pwr_switch_power(void) 528{ 529 struct acpi_powerresource *rp; 530 ACPI_STATUS status; 531 int cur; 532 533 FUNCTION_TRACE(__func__); 534 535 /* 536 * Sweep the list forwards turning things on. 537 */ 538 TAILQ_FOREACH(rp, &acpi_powerresources, ap_link) { 539 if (TAILQ_FIRST(&rp->ap_references) == NULL) { 540 DEBUG_PRINT(TRACE_OBJECTS, ("%s has no references, not turning on\n", 541 acpi_name(rp->ap_resource))); 542 continue; 543 } 544 545 /* we could cache this if we trusted it not to change under us */ 546 if ((status = acpi_EvaluateInteger(rp->ap_resource, "_STA", &cur)) != AE_OK) { 547 DEBUG_PRINT(TRACE_OBJECTS, ("can't get status of %s - %d\n", 548 acpi_name(rp->ap_resource), status)); 549 continue; /* XXX is this correct? Always switch if in doubt? */ 550 } 551 552 /* 553 * Switch if required. Note that we ignore the result of the switch 554 * effort; we don't know what to do if it fails, so checking wouldn't 555 * help much. 556 */ 557 if (cur != ACPI_PWR_ON) { 558 if (ACPI_FAILURE(status = AcpiEvaluateObject(rp->ap_resource, "_ON", NULL, NULL))) { 559 DEBUG_PRINT(TRACE_OBJECTS, ("failed to switch %s on - %s\n", 560 acpi_name(rp->ap_resource), AcpiFormatException(status))); 561 } else { 562 DEBUG_PRINT(TRACE_OBJECTS, ("switched %s on\n", acpi_name(rp->ap_resource))); 563 } 564 } else { 565 DEBUG_PRINT(TRACE_OBJECTS, ("%s is already on\n", acpi_name(rp->ap_resource))); 566 } 567 } 568 569 /* 570 * Sweep the list backwards turning things off. 571 */ 572 TAILQ_FOREACH_REVERSE(rp, &acpi_powerresources, acpi_powerresource_list, ap_link) { 573 if (TAILQ_FIRST(&rp->ap_references) != NULL) { 574 DEBUG_PRINT(TRACE_OBJECTS, ("%s has references, not turning off\n", 575 acpi_name(rp->ap_resource))); 576 continue; 577 } 578 579 /* we could cache this if we trusted it not to change under us */ 580 if ((status = acpi_EvaluateInteger(rp->ap_resource, "_STA", &cur)) != AE_OK) { 581 DEBUG_PRINT(TRACE_OBJECTS, ("can't get status of %s - %d\n", 582 acpi_name(rp->ap_resource), status)); 583 continue; /* XXX is this correct? Always switch if in doubt? */ 584 } 585 586 /* 587 * Switch if required. Note that we ignore the result of the switch 588 * effort; we don't know what to do if it fails, so checking wouldn't 589 * help much. 590 */ 591 if (cur != ACPI_PWR_OFF) { 592 if (ACPI_FAILURE(status = AcpiEvaluateObject(rp->ap_resource, "_OFF", NULL, NULL))) { 593 DEBUG_PRINT(TRACE_OBJECTS, ("failed to switch %s off - %s\n", 594 acpi_name(rp->ap_resource), AcpiFormatException(status))); 595 } else { 596 DEBUG_PRINT(TRACE_OBJECTS, ("switched %s off\n", acpi_name(rp->ap_resource))); 597 } 598 } else { 599 DEBUG_PRINT(TRACE_OBJECTS, ("%s is already off\n", acpi_name(rp->ap_resource))); 600 } 601 } 602 return_ACPI_STATUS(AE_OK); 603} 604 605/* 606 * Find a power resource's control structure. 607 */ 608static struct acpi_powerresource * 609acpi_pwr_find_resource(ACPI_HANDLE res) 610{ 611 struct acpi_powerresource *rp; 612 613 FUNCTION_TRACE(__func__); 614 615 TAILQ_FOREACH(rp, &acpi_powerresources, ap_link) 616 if (rp->ap_resource == res) 617 break; 618 return_VALUE(rp); 619} 620 621/* 622 * Find a power consumer's control structure. 623 */ 624static struct acpi_powerconsumer * 625acpi_pwr_find_consumer(ACPI_HANDLE consumer) 626{ 627 struct acpi_powerconsumer *pc; 628 629 FUNCTION_TRACE(__func__); 630 631 TAILQ_FOREACH(pc, &acpi_powerconsumers, ac_link) 632 if (pc->ac_consumer == consumer) 633 break; 634 return_VALUE(pc); 635} 636 637