1/* $NetBSD: acpi_power.c,v 1.36 2022/05/31 20:28:57 mrg Exp $ */ 2 3/*- 4 * Copyright (c) 2009, 2010, 2011 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jukka Ruohonen. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32/*- 33 * Copyright (c) 2001 Michael Smith 34 * All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 45 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 46 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 47 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 48 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 49 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 50 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 51 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 52 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 53 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 54 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 55 * SUCH DAMAGE. 56 */ 57 58#include <sys/cdefs.h> 59__KERNEL_RCSID(0, "$NetBSD: acpi_power.c,v 1.36 2022/05/31 20:28:57 mrg Exp $"); 60 61#include "pci.h" 62 63#include <sys/param.h> 64#include <sys/kmem.h> 65#include <sys/mutex.h> 66#include <sys/sysctl.h> 67 68#include <dev/acpi/acpireg.h> 69#include <dev/acpi/acpivar.h> 70#include <dev/acpi/acpi_pci.h> 71#include <dev/acpi/acpi_power.h> 72 73#define _COMPONENT ACPI_BUS_COMPONENT 74ACPI_MODULE_NAME ("acpi_power") 75 76#define ACPI_STA_POW_OFF 0x00 77#define ACPI_STA_POW_ON 0x01 78 79struct acpi_power_res { 80 ACPI_HANDLE res_handle; 81 ACPI_INTEGER res_level; 82 ACPI_INTEGER res_order; 83 ACPI_HANDLE res_ref[5]; 84 char res_name[5]; 85 kmutex_t res_mutex; 86 87 TAILQ_ENTRY(acpi_power_res) res_list; 88}; 89 90static TAILQ_HEAD(, acpi_power_res) res_head = 91 TAILQ_HEAD_INITIALIZER(res_head); 92 93static int32_t acpi_power_acpinode = CTL_EOL; 94static int32_t acpi_power_powernode = CTL_EOL; 95 96static struct acpi_power_res *acpi_power_res_init(ACPI_HANDLE); 97static struct acpi_power_res *acpi_power_res_get(ACPI_HANDLE); 98 99static ACPI_STATUS acpi_power_get_direct(struct acpi_devnode *); 100static ACPI_STATUS acpi_power_get_indirect(struct acpi_devnode *); 101static ACPI_STATUS acpi_power_switch(struct acpi_devnode *, 102 int, bool); 103static ACPI_STATUS acpi_power_res_ref(struct acpi_power_res *, 104 ACPI_HANDLE); 105static ACPI_STATUS acpi_power_res_deref(struct acpi_power_res *, 106 ACPI_HANDLE); 107static ACPI_STATUS acpi_power_res_sta(ACPI_OBJECT *, void *); 108 109static ACPI_OBJECT *acpi_power_pkg_get(ACPI_HANDLE, int); 110static int acpi_power_sysctl(SYSCTLFN_PROTO); 111static const char *acpi_xname(ACPI_HANDLE); 112 113static struct acpi_power_res * 114acpi_power_res_init(ACPI_HANDLE hdl) 115{ 116 struct acpi_power_res *tmp = NULL; 117 struct acpi_power_res *res = NULL; 118 ACPI_OBJECT *obj; 119 ACPI_BUFFER buf; 120 ACPI_STATUS rv; 121 size_t i; 122 123 rv = acpi_eval_struct(hdl, NULL, &buf); 124 125 if (ACPI_FAILURE(rv)) 126 goto out; 127 128 obj = buf.Pointer; 129 130 if (obj->Type != ACPI_TYPE_POWER) { 131 rv = AE_TYPE; 132 goto out; 133 } 134 135 res = kmem_zalloc(sizeof(*res), KM_SLEEP); 136 res->res_handle = hdl; 137 res->res_level = obj->PowerResource.SystemLevel; 138 res->res_order = obj->PowerResource.ResourceOrder; 139 140 (void)strlcpy(res->res_name, 141 acpi_xname(hdl), sizeof(res->res_name)); 142 143 for (i = 0; i < __arraycount(res->res_ref); i++) 144 res->res_ref[i] = NULL; 145 146 mutex_init(&res->res_mutex, MUTEX_DEFAULT, IPL_NONE); 147 148 /* 149 * Power resources should be ordered. 150 * 151 * These *should* be enabled from low values to high 152 * values and disabled from high values to low values. 153 */ 154 TAILQ_FOREACH(tmp, &res_head, res_list) { 155 156 if (res->res_order < tmp->res_order) { 157 TAILQ_INSERT_BEFORE(tmp, res, res_list); 158 break; 159 } 160 } 161 162 if (tmp == NULL) 163 TAILQ_INSERT_TAIL(&res_head, res, res_list); 164 165 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s added to the " 166 "power resource queue\n", res->res_name)); 167 168out: 169 if (buf.Pointer != NULL) 170 ACPI_FREE(buf.Pointer); 171 172 return res; 173} 174 175static struct acpi_power_res * 176acpi_power_res_get(ACPI_HANDLE hdl) 177{ 178 struct acpi_power_res *res; 179 180 TAILQ_FOREACH(res, &res_head, res_list) { 181 182 if (res->res_handle == hdl) 183 return res; 184 } 185 186 return acpi_power_res_init(hdl); 187} 188 189bool 190acpi_power_register(ACPI_HANDLE hdl) 191{ 192 return true; 193} 194 195void 196acpi_power_deregister(ACPI_HANDLE hdl) 197{ 198 struct acpi_devnode *ad = acpi_match_node(hdl); 199 struct acpi_power_res *res; 200 201 if (ad == NULL) 202 return; 203 204 /* 205 * Remove all references in each resource. 206 */ 207 TAILQ_FOREACH(res, &res_head, res_list) 208 (void)acpi_power_res_deref(res, ad->ad_handle); 209} 210 211/* 212 * Get the D-state of an ACPI device node. 213 */ 214bool 215acpi_power_get(ACPI_HANDLE hdl, int *state) 216{ 217 struct acpi_devnode *ad = acpi_match_node(hdl); 218 ACPI_STATUS rv; 219 220 if (ad == NULL) 221 return false; 222 223 /* 224 * As _PSC may be broken, first try to 225 * retrieve the power state indirectly 226 * via power resources. 227 */ 228 rv = acpi_power_get_indirect(ad); 229 230 if (ACPI_FAILURE(rv)) 231 rv = acpi_power_get_direct(ad); 232 233 if (ACPI_FAILURE(rv)) 234 goto fail; 235 236 KASSERT(ad->ad_state != ACPI_STATE_ERROR); 237 238 if (ad->ad_state < ACPI_STATE_D0 || ad->ad_state > ACPI_STATE_D3) { 239 rv = AE_BAD_VALUE; 240 goto fail; 241 } 242 243 if (state != NULL) 244 *state = ad->ad_state; 245 246 return true; 247 248fail: 249 ad->ad_state = ACPI_STATE_ERROR; 250 251 if (state != NULL) 252 *state = ad->ad_state; 253 254 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "failed to get power state " 255 "for %s: %s\n", ad->ad_name, AcpiFormatException(rv))); 256 257 return false; 258} 259 260static ACPI_STATUS 261acpi_power_get_direct(struct acpi_devnode *ad) 262{ 263 ACPI_INTEGER val = 0; 264 ACPI_STATUS rv; 265 266 rv = acpi_eval_integer(ad->ad_handle, "_PSC", &val); 267 268 KDASSERT((uint64_t)val < INT_MAX); 269 270 ad->ad_state = (int)val; 271 272 return rv; 273} 274 275static ACPI_STATUS 276acpi_power_get_indirect(struct acpi_devnode *ad) 277{ 278 ACPI_OBJECT *pkg; 279 ACPI_STATUS rv; 280 int i; 281 282 CTASSERT(ACPI_STATE_D0 == 0 && ACPI_STATE_D1 == 1); 283 CTASSERT(ACPI_STATE_D2 == 2 && ACPI_STATE_D3 == 3); 284 285 /* 286 * The device is in a given D-state if all resources are on. 287 * To derive this, evaluate all elements in each _PRx package 288 * (x = 0 ... 3) and break if the noted condition becomes true. 289 */ 290 for (ad->ad_state = ACPI_STATE_D3, i = 0; i < ACPI_STATE_D3; i++) { 291 292 pkg = acpi_power_pkg_get(ad->ad_handle, i); 293 294 if (pkg == NULL) 295 continue; 296 297 /* 298 * For each element in the _PRx package, evaluate _STA 299 * and return AE_OK only if all power resources are on. 300 */ 301 rv = acpi_foreach_package_object(pkg, acpi_power_res_sta, ad); 302 303 if (ACPI_FAILURE(rv) && rv != AE_CTRL_FALSE) 304 goto out; 305 306 if (ACPI_SUCCESS(rv)) { 307 ad->ad_state = i; 308 goto out; 309 } 310 311 ACPI_FREE(pkg); pkg = NULL; 312 } 313 314 KASSERT(ad->ad_state == ACPI_STATE_D3); 315 316 return AE_OK; 317 318out: 319 ACPI_FREE(pkg); 320 321 return rv; 322} 323 324/* 325 * Set the D-state of an ACPI device node. 326 */ 327bool 328acpi_power_set(ACPI_HANDLE hdl, int state) 329{ 330 struct acpi_devnode *ad = acpi_match_node(hdl); 331 ACPI_STATUS rv; 332 char path[5]; 333 int old; 334 335 if (ad == NULL) 336 return false; 337 338 if (state < ACPI_STATE_D0 || state > ACPI_STATE_D3) { 339 rv = AE_BAD_PARAMETER; 340 goto fail; 341 } 342 343 if (acpi_power_get(ad->ad_handle, &old) != true) { 344 rv = AE_NOT_FOUND; 345 goto fail; 346 } 347 348 KASSERT(ad->ad_state == old); 349 KASSERT(ad->ad_state != ACPI_STATE_ERROR); 350 351 if (ad->ad_state == state) { 352 rv = AE_ALREADY_EXISTS; 353 goto fail; 354 } 355 356 /* 357 * It is only possible to go to D0 ("on") from D3 ("off"). 358 */ 359 if (ad->ad_state == ACPI_STATE_D3 && state != ACPI_STATE_D0) { 360 rv = AE_BAD_PARAMETER; 361 goto fail; 362 } 363 364 /* 365 * As noted in ACPI 4.0 (appendix A.2.1), the bus power state 366 * should never be lower than the highest state of one of its 367 * devices. Consequently, we cannot set the state to a lower 368 * (i.e. higher power) state than the parent device's state. 369 */ 370 if ((ad->ad_parent != NULL) && 371 (ad->ad_parent->ad_flags & ACPI_DEVICE_POWER) != 0) { 372 373 if (ad->ad_parent->ad_state > state) { 374 rv = AE_ABORT_METHOD; 375 goto fail; 376 } 377 } 378 379 /* 380 * We first sweep through the resources required for the target 381 * state, turning things on and building references. After this 382 * we dereference the resources required for the current state, 383 * turning the resources off as we go. 384 */ 385 rv = acpi_power_switch(ad, state, true); 386 387 if (ACPI_FAILURE(rv) && rv != AE_CTRL_CONTINUE) 388 goto fail; 389 390 rv = acpi_power_switch(ad, ad->ad_state, false); 391 392 if (ACPI_FAILURE(rv) && rv != AE_CTRL_CONTINUE) 393 goto fail; 394 395 /* 396 * Last but not least, invoke the power state switch method, 397 * if available. Because some systems use only _PSx for the 398 * power state transitions, we do this even if there is no _PRx. 399 */ 400 (void)snprintf(path, sizeof(path), "_PS%d", state); 401 (void)AcpiEvaluateObject(ad->ad_handle, path, NULL, NULL); 402 403 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s turned from " 404 "D%d to D%d\n", ad->ad_name, old, state)); 405 406 ad->ad_state = state; 407 408 return true; 409 410fail: 411 ad->ad_state = ACPI_STATE_ERROR; 412 413 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "failed to set power state to D%d " 414 "for %s: %s\n", state, ad->ad_name, AcpiFormatException(rv))); 415 416 return false; 417} 418 419static ACPI_STATUS 420acpi_power_switch(struct acpi_devnode *ad, int state, bool on) 421{ 422 ACPI_OBJECT *elm, *pkg; 423 ACPI_STATUS rv = AE_OK; 424 ACPI_HANDLE hdl; 425 uint32_t i, n; 426 427 /* 428 * For each element in the _PRx package, fetch 429 * the reference handle, search for this handle 430 * from the power resource queue, and turn the 431 * resource behind the handle on or off. 432 */ 433 pkg = acpi_power_pkg_get(ad->ad_handle, state); 434 435 if (pkg == NULL) 436 return AE_CTRL_CONTINUE; 437 438 n = pkg->Package.Count; 439 440 for (i = 0; i < n; i++) { 441 442 elm = &pkg->Package.Elements[i]; 443 rv = acpi_eval_reference_handle(elm, &hdl); 444 445 if (ACPI_FAILURE(rv)) 446 continue; 447 448 (void)acpi_power_res(hdl, ad->ad_handle, on); 449 } 450 451 ACPI_FREE(pkg); 452 453 return rv; 454} 455 456ACPI_STATUS 457acpi_power_res(ACPI_HANDLE hdl, ACPI_HANDLE ref, bool on) 458{ 459 struct acpi_power_res *res; 460 const char *str; 461 ACPI_STATUS rv; 462 463 /* 464 * Search for the resource. 465 */ 466 res = acpi_power_res_get(hdl); 467 468 if (res == NULL) 469 return AE_NOT_FOUND; 470 471 if (ref == NULL) 472 return AE_BAD_PARAMETER; 473 474 /* 475 * Adjust the reference counting. This is 476 * necessary since a single power resource 477 * can be shared by multiple devices. 478 */ 479 if (on) { 480 rv = acpi_power_res_ref(res, ref); 481 str = "_ON"; 482 } else { 483 rv = acpi_power_res_deref(res, ref); 484 str = "_OFF"; 485 } 486 487 if (ACPI_FAILURE(rv)) 488 return rv; 489 490 /* 491 * Turn the resource on or off. 492 */ 493 return AcpiEvaluateObject(res->res_handle, str, NULL, NULL); 494} 495 496static ACPI_STATUS 497acpi_power_res_ref(struct acpi_power_res *res, ACPI_HANDLE ref) 498{ 499 size_t i, j = SIZE_MAX; 500 501 mutex_enter(&res->res_mutex); 502 503 for (i = 0; i < __arraycount(res->res_ref); i++) { 504 505 /* 506 * Do not error out if the handle 507 * has already been referenced. 508 */ 509 if (res->res_ref[i] == ref) { 510 mutex_exit(&res->res_mutex); 511 return AE_OK; 512 } 513 514 if (j == SIZE_MAX && res->res_ref[i] == NULL) 515 j = i; 516 } 517 518 if (j == SIZE_MAX) { 519 mutex_exit(&res->res_mutex); 520 return AE_LIMIT; 521 } 522 523 res->res_ref[j] = ref; 524 mutex_exit(&res->res_mutex); 525 526 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s referenced " 527 "by %s\n", res->res_name, acpi_xname(ref))); 528 529 return AE_OK; 530} 531 532static ACPI_STATUS 533acpi_power_res_deref(struct acpi_power_res *res, ACPI_HANDLE ref) 534{ 535 size_t i; 536 537 mutex_enter(&res->res_mutex); 538 539 for (i = 0; i < __arraycount(res->res_ref); i++) { 540 541 if (res->res_ref[i] != ref) 542 continue; 543 544 res->res_ref[i] = NULL; 545 mutex_exit(&res->res_mutex); 546 547 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s dereferenced " 548 "by %s\n", res->res_name, acpi_xname(ref))); 549 550 return AE_OK; 551 } 552 553 /* 554 * If the array remains to be non-empty, 555 * something else is using the resource 556 * and hence it can not be turned off. 557 */ 558 mutex_exit(&res->res_mutex); 559 560 return AE_ABORT_METHOD; 561} 562 563static ACPI_STATUS 564acpi_power_res_sta(ACPI_OBJECT *elm, void *arg) 565{ 566 ACPI_INTEGER val; 567 ACPI_HANDLE hdl; 568 ACPI_STATUS rv; 569 570 rv = acpi_eval_reference_handle(elm, &hdl); 571 572 if (ACPI_FAILURE(rv)) 573 goto fail; 574 575 rv = acpi_eval_integer(hdl, "_STA", &val); 576 577 if (ACPI_FAILURE(rv)) 578 goto fail; 579 580 KDASSERT((uint64_t)val < INT_MAX); 581 582 if ((int)val != ACPI_STA_POW_ON && (int)val != ACPI_STA_POW_OFF) 583 return AE_BAD_VALUE; 584 585 if ((int)val != ACPI_STA_POW_ON) 586 return AE_CTRL_FALSE; /* XXX: Not an error. */ 587 588 return AE_OK; 589 590fail: 591 if (rv == AE_CTRL_FALSE) 592 rv = AE_ERROR; 593 594 ACPI_DEBUG_PRINT((ACPI_DB_DEBUG_OBJECT, "failed to evaluate _STA " 595 "for %s: %s\n", acpi_xname(hdl), AcpiFormatException(rv))); 596 597 return rv; 598} 599 600static ACPI_OBJECT * 601acpi_power_pkg_get(ACPI_HANDLE hdl, int state) 602{ 603 char path[5] = "_PR?"; 604 ACPI_OBJECT *obj; 605 ACPI_BUFFER buf; 606 ACPI_STATUS rv; 607 608 path[3] = '0' + state; 609 610 rv = acpi_eval_struct(hdl, path, &buf); 611 612 if (ACPI_FAILURE(rv)) 613 goto fail; 614 615 if (buf.Length == 0) { 616 rv = AE_LIMIT; 617 goto fail; 618 } 619 620 obj = buf.Pointer; 621 622 if (obj->Type != ACPI_TYPE_PACKAGE) { 623 rv = AE_TYPE; 624 goto fail; 625 } 626 627 if (obj->Package.Count == 0) { 628 rv = AE_LIMIT; 629 goto fail; 630 } 631 632 return obj; 633 634fail: 635 if (buf.Pointer != NULL) 636 ACPI_FREE(buf.Pointer); 637 638 ACPI_DEBUG_PRINT((ACPI_DB_DEBUG_OBJECT, "failed to evaluate %s for " 639 "%s: %s\n", path, acpi_xname(hdl), AcpiFormatException(rv))); 640 641 return NULL; 642} 643 644SYSCTL_SETUP(sysctl_acpi_power_setup, "sysctl hw.acpi.power subtree setup") 645{ 646 const struct sysctlnode *anode; 647 int err; 648 649 err = sysctl_createv(NULL, 0, NULL, &anode, 650 CTLFLAG_PERMANENT, CTLTYPE_NODE, "acpi", 651 NULL, NULL, 0, NULL, 0, 652 CTL_HW, CTL_CREATE, CTL_EOL); 653 654 if (err != 0) 655 return; 656 657 acpi_power_acpinode = anode->sysctl_num; 658 659 err = sysctl_createv(NULL, 0, &anode, &anode, 660 CTLFLAG_PERMANENT, CTLTYPE_NODE, 661 "power", SYSCTL_DESCR("ACPI device power states"), 662 NULL, 0, NULL, 0, 663 CTL_CREATE, CTL_EOL); 664 665 if (err != 0) 666 return; 667 668 acpi_power_powernode = anode->sysctl_num; 669} 670 671void 672acpi_power_add(struct acpi_devnode *ad) 673{ 674 const char *str = NULL; 675 int err; 676 677 KASSERT(ad != NULL && ad->ad_root != NULL); 678 KASSERT((ad->ad_flags & ACPI_DEVICE_POWER) != 0); 679 680 if (acpi_power_acpinode == CTL_EOL || 681 acpi_power_powernode == CTL_EOL) 682 return; 683 684 if (ad->ad_device != NULL) 685 str = device_xname(ad->ad_device); 686#if NPCI > 0 687 else { 688 device_t dev = acpi_pcidev_find_dev(ad); 689 690 if (dev != NULL) 691 str = device_xname(dev); 692 } 693#endif 694 695 if (str == NULL) 696 return; 697 698 err = sysctl_createv(NULL, 0, NULL, NULL, 699 CTLFLAG_READONLY, CTLTYPE_STRING, str, 700 NULL, acpi_power_sysctl, 0, (void *)ad, 0, CTL_HW, 701 acpi_power_acpinode, acpi_power_powernode, 702 CTL_CREATE, CTL_EOL); 703 704 if (err != 0) 705 aprint_error_dev(ad->ad_root, "sysctl_createv" 706 "(hw.acpi.power.%s) failed (err %d)\n", str, err); 707} 708 709static int 710acpi_power_sysctl(SYSCTLFN_ARGS) 711{ 712 struct acpi_devnode *ad; 713 struct sysctlnode node; 714 int err, state; 715 char t[3]; 716 717 node = *rnode; 718 ad = rnode->sysctl_data; 719 720 if (acpi_power_get(ad->ad_handle, &state) != true) 721 state = 0; 722 723 (void)memset(t, '\0', sizeof(t)); 724 (void)snprintf(t, sizeof(t), "D%d", state); 725 726 node.sysctl_data = &t; 727 728 err = sysctl_lookup(SYSCTLFN_CALL(&node)); 729 730 if (err || newp == NULL) 731 return err; 732 733 return 0; 734} 735 736/* 737 * XXX: Move this to acpi_util.c by refactoring 738 * acpi_name() to optionally return a single name. 739 */ 740static const char * 741acpi_xname(ACPI_HANDLE hdl) 742{ 743 static char str[5]; 744 ACPI_BUFFER buf; 745 ACPI_STATUS rv; 746 747 buf.Pointer = str; 748 buf.Length = sizeof(str); 749 750 rv = AcpiGetName(hdl, ACPI_SINGLE_NAME, &buf); 751 752 if (ACPI_FAILURE(rv)) 753 return "????"; 754 755 return str; 756} 757