1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Architecture-specific ACPI-based support for suspend-to-idle. 4 * 5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 6 * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> 7 * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com> 8 * 9 * On platforms supporting the Low Power S0 Idle interface there is an ACPI 10 * device object with the PNP0D80 compatible device ID (System Power Management 11 * Controller) and a specific _DSM method under it. That method, if present, 12 * can be used to indicate to the platform that the OS is transitioning into a 13 * low-power state in which certain types of activity are not desirable or that 14 * it is leaving such a state, which allows the platform to adjust its operation 15 * mode accordingly. 16 */ 17 18 #include <linux/acpi.h> 19 #include <linux/device.h> 20 #include <linux/dmi.h> 21 #include <linux/suspend.h> 22 23 #include "../sleep.h" 24 25 #ifdef CONFIG_SUSPEND 26 27 static bool sleep_no_lps0 __read_mostly; 28 module_param(sleep_no_lps0, bool, 0644); 29 MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface"); 30 31 static bool prefer_microsoft_dsm_guid __read_mostly; 32 module_param(prefer_microsoft_dsm_guid, bool, 0644); 33 MODULE_PARM_DESC(prefer_microsoft_dsm_guid, "Prefer using Microsoft GUID in LPS0 device _DSM evaluation"); 34 35 static const struct acpi_device_id lps0_device_ids[] = { 36 {"PNP0D80", }, 37 {"", }, 38 }; 39 40 /* Microsoft platform agnostic UUID */ 41 #define ACPI_LPS0_DSM_UUID_MICROSOFT "11e00d56-ce64-47ce-837b-1f898f9aa461" 42 43 #define ACPI_LPS0_DSM_UUID "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66" 44 45 #define ACPI_LPS0_GET_DEVICE_CONSTRAINTS 1 46 #define ACPI_LPS0_SCREEN_OFF 3 47 #define ACPI_LPS0_SCREEN_ON 4 48 #define ACPI_LPS0_ENTRY 5 49 #define ACPI_LPS0_EXIT 6 50 #define ACPI_LPS0_MS_ENTRY 7 51 #define ACPI_LPS0_MS_EXIT 8 52 53 /* AMD */ 54 #define ACPI_LPS0_DSM_UUID_AMD "e3f32452-febc-43ce-9039-932122d37721" 55 #define ACPI_LPS0_ENTRY_AMD 2 56 #define ACPI_LPS0_EXIT_AMD 3 57 #define ACPI_LPS0_SCREEN_OFF_AMD 4 58 #define ACPI_LPS0_SCREEN_ON_AMD 5 59 60 static acpi_handle lps0_device_handle; 61 static guid_t lps0_dsm_guid; 62 static int lps0_dsm_func_mask; 63 64 static guid_t lps0_dsm_guid_microsoft; 65 static int lps0_dsm_func_mask_microsoft; 66 67 /* Device constraint entry structure */ 68 struct lpi_device_info { 69 char *name; 70 int enabled; 71 union acpi_object *package; 72 }; 73 74 /* Constraint package structure */ 75 struct lpi_device_constraint { 76 int uid; 77 int min_dstate; 78 int function_states; 79 }; 80 81 struct lpi_constraints { 82 acpi_handle handle; 83 int min_dstate; 84 }; 85 86 /* AMD Constraint package structure */ 87 struct lpi_device_constraint_amd { 88 char *name; 89 int enabled; 90 int function_states; 91 int min_dstate; 92 }; 93 94 static LIST_HEAD(lps0_s2idle_devops_head); 95 96 static struct lpi_constraints *lpi_constraints_table; 97 static int lpi_constraints_table_size; 98 static int rev_id; 99 100 static void lpi_device_get_constraints_amd(void) 101 { 102 union acpi_object *out_obj; 103 int i, j, k; 104 105 out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid, 106 rev_id, ACPI_LPS0_GET_DEVICE_CONSTRAINTS, 107 NULL, ACPI_TYPE_PACKAGE); 108 109 acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n", 110 out_obj ? "successful" : "failed"); 111 112 if (!out_obj) 113 return; 114 115 for (i = 0; i < out_obj->package.count; i++) { 116 union acpi_object *package = &out_obj->package.elements[i]; 117 118 if (package->type == ACPI_TYPE_PACKAGE) { 119 lpi_constraints_table = kcalloc(package->package.count, 120 sizeof(*lpi_constraints_table), 121 GFP_KERNEL); 122 123 if (!lpi_constraints_table) 124 goto free_acpi_buffer; 125 126 acpi_handle_debug(lps0_device_handle, 127 "LPI: constraints list begin:\n"); 128 129 for (j = 0; j < package->package.count; ++j) { 130 union acpi_object *info_obj = &package->package.elements[j]; 131 struct lpi_device_constraint_amd dev_info = {}; 132 struct lpi_constraints *list; 133 acpi_status status; 134 135 for (k = 0; k < info_obj->package.count; ++k) { 136 union acpi_object *obj = &info_obj->package.elements[k]; 137 138 list = &lpi_constraints_table[lpi_constraints_table_size]; 139 list->min_dstate = -1; 140 141 switch (k) { 142 case 0: 143 dev_info.enabled = obj->integer.value; 144 break; 145 case 1: 146 dev_info.name = obj->string.pointer; 147 break; 148 case 2: 149 dev_info.function_states = obj->integer.value; 150 break; 151 case 3: 152 dev_info.min_dstate = obj->integer.value; 153 break; 154 } 155 156 if (!dev_info.enabled || !dev_info.name || 157 !dev_info.min_dstate) 158 continue; 159 160 status = acpi_get_handle(NULL, dev_info.name, 161 &list->handle); 162 if (ACPI_FAILURE(status)) 163 continue; 164 165 acpi_handle_debug(lps0_device_handle, 166 "Name:%s\n", dev_info.name); 167 168 list->min_dstate = dev_info.min_dstate; 169 170 if (list->min_dstate < 0) { 171 acpi_handle_debug(lps0_device_handle, 172 "Incomplete constraint defined\n"); 173 continue; 174 } 175 } 176 lpi_constraints_table_size++; 177 } 178 } 179 } 180 181 acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n"); 182 183 free_acpi_buffer: 184 ACPI_FREE(out_obj); 185 } 186 187 static void lpi_device_get_constraints(void) 188 { 189 union acpi_object *out_obj; 190 int i; 191 192 out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid, 193 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS, 194 NULL, ACPI_TYPE_PACKAGE); 195 196 acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n", 197 out_obj ? "successful" : "failed"); 198 199 if (!out_obj) 200 return; 201 202 lpi_constraints_table = kcalloc(out_obj->package.count, 203 sizeof(*lpi_constraints_table), 204 GFP_KERNEL); 205 if (!lpi_constraints_table) 206 goto free_acpi_buffer; 207 208 acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n"); 209 210 for (i = 0; i < out_obj->package.count; i++) { 211 struct lpi_constraints *constraint; 212 acpi_status status; 213 union acpi_object *package = &out_obj->package.elements[i]; 214 struct lpi_device_info info = { }; 215 int package_count = 0, j; 216 217 if (!package) 218 continue; 219 220 for (j = 0; j < package->package.count; ++j) { 221 union acpi_object *element = 222 &(package->package.elements[j]); 223 224 switch (element->type) { 225 case ACPI_TYPE_INTEGER: 226 info.enabled = element->integer.value; 227 break; 228 case ACPI_TYPE_STRING: 229 info.name = element->string.pointer; 230 break; 231 case ACPI_TYPE_PACKAGE: 232 package_count = element->package.count; 233 info.package = element->package.elements; 234 break; 235 } 236 } 237 238 if (!info.enabled || !info.package || !info.name) 239 continue; 240 241 constraint = &lpi_constraints_table[lpi_constraints_table_size]; 242 243 status = acpi_get_handle(NULL, info.name, &constraint->handle); 244 if (ACPI_FAILURE(status)) 245 continue; 246 247 acpi_handle_debug(lps0_device_handle, 248 "index:%d Name:%s\n", i, info.name); 249 250 constraint->min_dstate = -1; 251 252 for (j = 0; j < package_count; ++j) { 253 union acpi_object *info_obj = &info.package[j]; 254 union acpi_object *cnstr_pkg; 255 union acpi_object *obj; 256 struct lpi_device_constraint dev_info; 257 258 switch (info_obj->type) { 259 case ACPI_TYPE_INTEGER: 260 /* version */ 261 break; 262 case ACPI_TYPE_PACKAGE: 263 if (info_obj->package.count < 2) 264 break; 265 266 cnstr_pkg = info_obj->package.elements; 267 obj = &cnstr_pkg[0]; 268 dev_info.uid = obj->integer.value; 269 obj = &cnstr_pkg[1]; 270 dev_info.min_dstate = obj->integer.value; 271 272 acpi_handle_debug(lps0_device_handle, 273 "uid:%d min_dstate:%s\n", 274 dev_info.uid, 275 acpi_power_state_string(dev_info.min_dstate)); 276 277 constraint->min_dstate = dev_info.min_dstate; 278 break; 279 } 280 } 281 282 if (constraint->min_dstate < 0) { 283 acpi_handle_debug(lps0_device_handle, 284 "Incomplete constraint defined\n"); 285 continue; 286 } 287 288 lpi_constraints_table_size++; 289 } 290 291 acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n"); 292 293 free_acpi_buffer: 294 ACPI_FREE(out_obj); 295 } 296 297 static void lpi_check_constraints(void) 298 { 299 int i; 300 301 for (i = 0; i < lpi_constraints_table_size; ++i) { 302 acpi_handle handle = lpi_constraints_table[i].handle; 303 struct acpi_device *adev = acpi_fetch_acpi_dev(handle); 304 305 if (!adev) 306 continue; 307 308 acpi_handle_debug(handle, 309 "LPI: required min power state:%s current power state:%s\n", 310 acpi_power_state_string(lpi_constraints_table[i].min_dstate), 311 acpi_power_state_string(adev->power.state)); 312 313 if (!adev->flags.power_manageable) { 314 acpi_handle_info(handle, "LPI: Device not power manageable\n"); 315 lpi_constraints_table[i].handle = NULL; 316 continue; 317 } 318 319 if (adev->power.state < lpi_constraints_table[i].min_dstate) 320 acpi_handle_info(handle, 321 "LPI: Constraint not met; min power state:%s current power state:%s\n", 322 acpi_power_state_string(lpi_constraints_table[i].min_dstate), 323 acpi_power_state_string(adev->power.state)); 324 } 325 } 326 327 static void acpi_sleep_run_lps0_dsm(unsigned int func, unsigned int func_mask, guid_t dsm_guid) 328 { 329 union acpi_object *out_obj; 330 331 if (!(func_mask & (1 << func))) 332 return; 333 334 out_obj = acpi_evaluate_dsm(lps0_device_handle, &dsm_guid, 335 rev_id, func, NULL); 336 ACPI_FREE(out_obj); 337 338 acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n", 339 func, out_obj ? "successful" : "failed"); 340 } 341 342 static bool acpi_s2idle_vendor_amd(void) 343 { 344 return boot_cpu_data.x86_vendor == X86_VENDOR_AMD; 345 } 346 347 static int validate_dsm(acpi_handle handle, const char *uuid, int rev, guid_t *dsm_guid) 348 { 349 union acpi_object *obj; 350 int ret = -EINVAL; 351 352 guid_parse(uuid, dsm_guid); 353 obj = acpi_evaluate_dsm(handle, dsm_guid, rev, 0, NULL); 354 355 /* Check if the _DSM is present and as expected. */ 356 if (!obj || obj->type != ACPI_TYPE_BUFFER || obj->buffer.length == 0 || 357 obj->buffer.length > sizeof(u32)) { 358 acpi_handle_debug(handle, 359 "_DSM UUID %s rev %d function 0 evaluation failed\n", uuid, rev); 360 goto out; 361 } 362 363 ret = *(int *)obj->buffer.pointer; 364 acpi_handle_debug(handle, "_DSM UUID %s rev %d function mask: 0x%x\n", uuid, rev, ret); 365 366 out: 367 ACPI_FREE(obj); 368 return ret; 369 } 370 371 struct amd_lps0_hid_device_data { 372 const unsigned int rev_id; 373 const bool check_off_by_one; 374 const bool prefer_amd_guid; 375 }; 376 377 static const struct amd_lps0_hid_device_data amd_picasso = { 378 .rev_id = 0, 379 .check_off_by_one = true, 380 .prefer_amd_guid = false, 381 }; 382 383 static const struct amd_lps0_hid_device_data amd_cezanne = { 384 .rev_id = 0, 385 .check_off_by_one = false, 386 .prefer_amd_guid = false, 387 }; 388 389 static const struct amd_lps0_hid_device_data amd_rembrandt = { 390 .rev_id = 2, 391 .check_off_by_one = false, 392 .prefer_amd_guid = true, 393 }; 394 395 static const struct acpi_device_id amd_hid_ids[] = { 396 {"AMD0004", (kernel_ulong_t)&amd_picasso, }, 397 {"AMD0005", (kernel_ulong_t)&amd_picasso, }, 398 {"AMDI0005", (kernel_ulong_t)&amd_picasso, }, 399 {"AMDI0006", (kernel_ulong_t)&amd_cezanne, }, 400 {"AMDI0007", (kernel_ulong_t)&amd_rembrandt, }, 401 {} 402 }; 403 404 static int lps0_prefer_microsoft(const struct dmi_system_id *id) 405 { 406 pr_debug("Preferring Microsoft GUID.\n"); 407 prefer_microsoft_dsm_guid = true; 408 return 0; 409 } 410 411 static const struct dmi_system_id s2idle_dmi_table[] __initconst = { 412 { 413 /* 414 * ASUS TUF Gaming A17 FA707RE 415 * https://bugzilla.kernel.org/show_bug.cgi?id=216101 416 */ 417 .callback = lps0_prefer_microsoft, 418 .matches = { 419 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 420 DMI_MATCH(DMI_PRODUCT_NAME, "ASUS TUF Gaming A17"), 421 }, 422 }, 423 { 424 /* ASUS ROG Zephyrus G14 (2022) */ 425 .callback = lps0_prefer_microsoft, 426 .matches = { 427 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 428 DMI_MATCH(DMI_PRODUCT_NAME, "ROG Zephyrus G14 GA402"), 429 }, 430 }, 431 { 432 /* 433 * Lenovo Yoga Slim 7 Pro X 14ARH7 434 * https://bugzilla.kernel.org/show_bug.cgi?id=216473 : 82V2 435 * https://bugzilla.kernel.org/show_bug.cgi?id=216438 : 82TL 436 */ 437 .callback = lps0_prefer_microsoft, 438 .matches = { 439 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"), 440 DMI_MATCH(DMI_PRODUCT_NAME, "82"), 441 }, 442 }, 443 { 444 /* 445 * ASUSTeK COMPUTER INC. ROG Flow X13 GV301RE_GV301RE 446 * https://gitlab.freedesktop.org/drm/amd/-/issues/2148 447 */ 448 .callback = lps0_prefer_microsoft, 449 .matches = { 450 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 451 DMI_MATCH(DMI_PRODUCT_NAME, "ROG Flow X13 GV301"), 452 }, 453 }, 454 { 455 /* 456 * ASUSTeK COMPUTER INC. ROG Flow X16 GV601RW_GV601RW 457 * https://gitlab.freedesktop.org/drm/amd/-/issues/2148 458 */ 459 .callback = lps0_prefer_microsoft, 460 .matches = { 461 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 462 DMI_MATCH(DMI_PRODUCT_NAME, "ROG Flow X16 GV601"), 463 }, 464 }, 465 {} 466 }; 467 468 static int lps0_device_attach(struct acpi_device *adev, 469 const struct acpi_device_id *not_used) 470 { 471 if (lps0_device_handle) 472 return 0; 473 474 lps0_dsm_func_mask_microsoft = validate_dsm(adev->handle, 475 ACPI_LPS0_DSM_UUID_MICROSOFT, 0, 476 &lps0_dsm_guid_microsoft); 477 if (acpi_s2idle_vendor_amd()) { 478 static const struct acpi_device_id *dev_id; 479 const struct amd_lps0_hid_device_data *data; 480 481 for (dev_id = &amd_hid_ids[0]; dev_id->id[0]; dev_id++) 482 if (acpi_dev_hid_uid_match(adev, dev_id->id, NULL)) 483 break; 484 if (dev_id->id[0]) 485 data = (const struct amd_lps0_hid_device_data *) dev_id->driver_data; 486 else 487 data = &amd_rembrandt; 488 rev_id = data->rev_id; 489 lps0_dsm_func_mask = validate_dsm(adev->handle, 490 ACPI_LPS0_DSM_UUID_AMD, rev_id, &lps0_dsm_guid); 491 if (lps0_dsm_func_mask > 0x3 && data->check_off_by_one) { 492 lps0_dsm_func_mask = (lps0_dsm_func_mask << 1) | 0x1; 493 acpi_handle_debug(adev->handle, "_DSM UUID %s: Adjusted function mask: 0x%x\n", 494 ACPI_LPS0_DSM_UUID_AMD, lps0_dsm_func_mask); 495 } else if (lps0_dsm_func_mask_microsoft > 0 && data->prefer_amd_guid && 496 !prefer_microsoft_dsm_guid) { 497 lps0_dsm_func_mask_microsoft = -EINVAL; 498 acpi_handle_debug(adev->handle, "_DSM Using AMD method\n"); 499 } 500 } else { 501 rev_id = 1; 502 lps0_dsm_func_mask = validate_dsm(adev->handle, 503 ACPI_LPS0_DSM_UUID, rev_id, &lps0_dsm_guid); 504 if (!prefer_microsoft_dsm_guid) 505 lps0_dsm_func_mask_microsoft = -EINVAL; 506 } 507 508 if (lps0_dsm_func_mask < 0 && lps0_dsm_func_mask_microsoft < 0) 509 return 0; //function evaluation failed 510 511 lps0_device_handle = adev->handle; 512 513 if (acpi_s2idle_vendor_amd()) 514 lpi_device_get_constraints_amd(); 515 else 516 lpi_device_get_constraints(); 517 518 /* 519 * Use suspend-to-idle by default if ACPI_FADT_LOW_POWER_S0 is set in 520 * the FADT and the default suspend mode was not set from the command 521 * line. 522 */ 523 if ((acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) && 524 mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3) { 525 mem_sleep_current = PM_SUSPEND_TO_IDLE; 526 pr_info("Low-power S0 idle used by default for system suspend\n"); 527 } 528 529 /* 530 * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the 531 * EC GPE to be enabled while suspended for certain wakeup devices to 532 * work, so mark it as wakeup-capable. 533 */ 534 acpi_ec_mark_gpe_for_wake(); 535 536 return 0; 537 } 538 539 static struct acpi_scan_handler lps0_handler = { 540 .ids = lps0_device_ids, 541 .attach = lps0_device_attach, 542 }; 543 544 int acpi_s2idle_prepare_late(void) 545 { 546 struct acpi_s2idle_dev_ops *handler; 547 548 if (!lps0_device_handle || sleep_no_lps0) 549 return 0; 550 551 if (pm_debug_messages_on) 552 lpi_check_constraints(); 553 554 /* Screen off */ 555 if (lps0_dsm_func_mask > 0) 556 acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ? 557 ACPI_LPS0_SCREEN_OFF_AMD : 558 ACPI_LPS0_SCREEN_OFF, 559 lps0_dsm_func_mask, lps0_dsm_guid); 560 561 if (lps0_dsm_func_mask_microsoft > 0) 562 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF, 563 lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft); 564 565 /* LPS0 entry */ 566 if (lps0_dsm_func_mask > 0) 567 acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ? 568 ACPI_LPS0_ENTRY_AMD : 569 ACPI_LPS0_ENTRY, 570 lps0_dsm_func_mask, lps0_dsm_guid); 571 if (lps0_dsm_func_mask_microsoft > 0) { 572 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY, 573 lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft); 574 /* modern standby entry */ 575 acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_ENTRY, 576 lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft); 577 } 578 579 list_for_each_entry(handler, &lps0_s2idle_devops_head, list_node) { 580 if (handler->prepare) 581 handler->prepare(); 582 } 583 584 return 0; 585 } 586 587 void acpi_s2idle_restore_early(void) 588 { 589 struct acpi_s2idle_dev_ops *handler; 590 591 if (!lps0_device_handle || sleep_no_lps0) 592 return; 593 594 list_for_each_entry(handler, &lps0_s2idle_devops_head, list_node) 595 if (handler->restore) 596 handler->restore(); 597 598 /* Modern standby exit */ 599 if (lps0_dsm_func_mask_microsoft > 0) 600 acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_EXIT, 601 lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft); 602 603 /* LPS0 exit */ 604 if (lps0_dsm_func_mask > 0) 605 acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ? 606 ACPI_LPS0_EXIT_AMD : 607 ACPI_LPS0_EXIT, 608 lps0_dsm_func_mask, lps0_dsm_guid); 609 if (lps0_dsm_func_mask_microsoft > 0) 610 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT, 611 lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft); 612 613 /* Screen on */ 614 if (lps0_dsm_func_mask_microsoft > 0) 615 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON, 616 lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft); 617 if (lps0_dsm_func_mask > 0) 618 acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ? 619 ACPI_LPS0_SCREEN_ON_AMD : 620 ACPI_LPS0_SCREEN_ON, 621 lps0_dsm_func_mask, lps0_dsm_guid); 622 } 623 624 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = { 625 .begin = acpi_s2idle_begin, 626 .prepare = acpi_s2idle_prepare, 627 .prepare_late = acpi_s2idle_prepare_late, 628 .wake = acpi_s2idle_wake, 629 .restore_early = acpi_s2idle_restore_early, 630 .restore = acpi_s2idle_restore, 631 .end = acpi_s2idle_end, 632 }; 633 634 void __init acpi_s2idle_setup(void) 635 { 636 dmi_check_system(s2idle_dmi_table); 637 acpi_scan_add_handler(&lps0_handler); 638 s2idle_set_ops(&acpi_s2idle_ops_lps0); 639 } 640 641 int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg) 642 { 643 if (!lps0_device_handle || sleep_no_lps0) 644 return -ENODEV; 645 646 lock_system_sleep(); 647 list_add(&arg->list_node, &lps0_s2idle_devops_head); 648 unlock_system_sleep(); 649 650 return 0; 651 } 652 EXPORT_SYMBOL_GPL(acpi_register_lps0_dev); 653 654 void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg) 655 { 656 if (!lps0_device_handle || sleep_no_lps0) 657 return; 658 659 lock_system_sleep(); 660 list_del(&arg->list_node); 661 unlock_system_sleep(); 662 } 663 EXPORT_SYMBOL_GPL(acpi_unregister_lps0_dev); 664 665 #endif /* CONFIG_SUSPEND */ 666