1/* 2 * acpi_power.c - ACPI Bus Power Management ($Revision: 39 $) 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * 7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or (at 12 * your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License along 20 * with this program; if not, write to the Free Software Foundation, Inc., 21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 22 * 23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 24 */ 25 26/* 27 * ACPI power-managed devices may be controlled in two ways: 28 * 1. via "Device Specific (D-State) Control" 29 * 2. via "Power Resource Control". 30 * This module is used to manage devices relying on Power Resource Control. 31 * 32 * An ACPI "power resource object" describes a software controllable power 33 * plane, clock plane, or other resource used by a power managed device. 34 * A device may rely on multiple power resources, and a power resource 35 * may be shared by multiple devices. 36 */ 37 38#include <linux/kernel.h> 39#include <linux/module.h> 40#include <linux/init.h> 41#include <linux/types.h> 42#include <linux/slab.h> 43#include <acpi/acpi_bus.h> 44#include <acpi/acpi_drivers.h> 45#include "sleep.h" 46 47#define PREFIX "ACPI: " 48 49#define _COMPONENT ACPI_POWER_COMPONENT 50ACPI_MODULE_NAME("power"); 51#define ACPI_POWER_CLASS "power_resource" 52#define ACPI_POWER_DEVICE_NAME "Power Resource" 53#define ACPI_POWER_FILE_INFO "info" 54#define ACPI_POWER_FILE_STATUS "state" 55#define ACPI_POWER_RESOURCE_STATE_OFF 0x00 56#define ACPI_POWER_RESOURCE_STATE_ON 0x01 57#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF 58 59int acpi_power_nocheck; 60module_param_named(power_nocheck, acpi_power_nocheck, bool, 000); 61 62static int acpi_power_add(struct acpi_device *device); 63static int acpi_power_remove(struct acpi_device *device, int type); 64static int acpi_power_resume(struct acpi_device *device); 65 66static const struct acpi_device_id power_device_ids[] = { 67 {ACPI_POWER_HID, 0}, 68 {"", 0}, 69}; 70MODULE_DEVICE_TABLE(acpi, power_device_ids); 71 72static struct acpi_driver acpi_power_driver = { 73 .name = "power", 74 .class = ACPI_POWER_CLASS, 75 .ids = power_device_ids, 76 .ops = { 77 .add = acpi_power_add, 78 .remove = acpi_power_remove, 79 .resume = acpi_power_resume, 80 }, 81}; 82 83struct acpi_power_reference { 84 struct list_head node; 85 struct acpi_device *device; 86}; 87 88struct acpi_power_resource { 89 struct acpi_device * device; 90 acpi_bus_id name; 91 u32 system_level; 92 u32 order; 93 struct mutex resource_lock; 94 struct list_head reference; 95}; 96 97static struct list_head acpi_power_resource_list; 98 99/* -------------------------------------------------------------------------- 100 Power Resource Management 101 -------------------------------------------------------------------------- */ 102 103static int 104acpi_power_get_context(acpi_handle handle, 105 struct acpi_power_resource **resource) 106{ 107 int result = 0; 108 struct acpi_device *device = NULL; 109 110 111 if (!resource) 112 return -ENODEV; 113 114 result = acpi_bus_get_device(handle, &device); 115 if (result) { 116 printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle); 117 return result; 118 } 119 120 *resource = acpi_driver_data(device); 121 if (!*resource) 122 return -ENODEV; 123 124 return 0; 125} 126 127static int acpi_power_get_state(acpi_handle handle, int *state) 128{ 129 acpi_status status = AE_OK; 130 unsigned long long sta = 0; 131 char node_name[5]; 132 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 133 134 135 if (!handle || !state) 136 return -EINVAL; 137 138 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); 139 if (ACPI_FAILURE(status)) 140 return -ENODEV; 141 142 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON: 143 ACPI_POWER_RESOURCE_STATE_OFF; 144 145 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 146 147 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n", 148 node_name, 149 *state ? "on" : "off")); 150 151 return 0; 152} 153 154static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state) 155{ 156 int result = 0, state1; 157 u32 i = 0; 158 159 160 if (!list || !state) 161 return -EINVAL; 162 163 /* The state of the list is 'on' IFF all resources are 'on'. */ 164 165 for (i = 0; i < list->count; i++) { 166 /* 167 * The state of the power resource can be obtained by 168 * using the ACPI handle. In such case it is unnecessary to 169 * get the Power resource first and then get its state again. 170 */ 171 result = acpi_power_get_state(list->handles[i], &state1); 172 if (result) 173 return result; 174 175 *state = state1; 176 177 if (*state != ACPI_POWER_RESOURCE_STATE_ON) 178 break; 179 } 180 181 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n", 182 *state ? "on" : "off")); 183 184 return result; 185} 186 187static int acpi_power_on(acpi_handle handle, struct acpi_device *dev) 188{ 189 int result = 0; 190 int found = 0; 191 acpi_status status = AE_OK; 192 struct acpi_power_resource *resource = NULL; 193 struct list_head *node, *next; 194 struct acpi_power_reference *ref; 195 196 197 result = acpi_power_get_context(handle, &resource); 198 if (result) 199 return result; 200 201 mutex_lock(&resource->resource_lock); 202 list_for_each_safe(node, next, &resource->reference) { 203 ref = container_of(node, struct acpi_power_reference, node); 204 if (dev->handle == ref->device->handle) { 205 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already referenced by resource [%s]\n", 206 dev->pnp.bus_id, resource->name)); 207 found = 1; 208 break; 209 } 210 } 211 212 if (!found) { 213 ref = kmalloc(sizeof (struct acpi_power_reference), 214 irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL); 215 if (!ref) { 216 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "kmalloc() failed\n")); 217 mutex_unlock(&resource->resource_lock); 218 return -ENOMEM; 219 } 220 list_add_tail(&ref->node, &resource->reference); 221 ref->device = dev; 222 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] added to resource [%s] references\n", 223 dev->pnp.bus_id, resource->name)); 224 } 225 mutex_unlock(&resource->resource_lock); 226 227 status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL); 228 if (ACPI_FAILURE(status)) 229 return -ENODEV; 230 231 /* Update the power resource's _device_ power state */ 232 resource->device->power.state = ACPI_STATE_D0; 233 234 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned on\n", 235 resource->name)); 236 return 0; 237} 238 239static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev) 240{ 241 int result = 0; 242 acpi_status status = AE_OK; 243 struct acpi_power_resource *resource = NULL; 244 struct list_head *node, *next; 245 struct acpi_power_reference *ref; 246 247 result = acpi_power_get_context(handle, &resource); 248 if (result) 249 return result; 250 251 mutex_lock(&resource->resource_lock); 252 list_for_each_safe(node, next, &resource->reference) { 253 ref = container_of(node, struct acpi_power_reference, node); 254 if (dev->handle == ref->device->handle) { 255 list_del(&ref->node); 256 kfree(ref); 257 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] removed from resource [%s] references\n", 258 dev->pnp.bus_id, resource->name)); 259 break; 260 } 261 } 262 263 if (!list_empty(&resource->reference)) { 264 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cannot turn resource [%s] off - resource is in use\n", 265 resource->name)); 266 mutex_unlock(&resource->resource_lock); 267 return 0; 268 } 269 mutex_unlock(&resource->resource_lock); 270 271 status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL); 272 if (ACPI_FAILURE(status)) 273 return -ENODEV; 274 275 /* Update the power resource's _device_ power state */ 276 resource->device->power.state = ACPI_STATE_D3; 277 278 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n", 279 resource->name)); 280 281 return 0; 282} 283 284/** 285 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in 286 * ACPI 3.0) _PSW (Power State Wake) 287 * @dev: Device to handle. 288 * @enable: 0 - disable, 1 - enable the wake capabilities of the device. 289 * @sleep_state: Target sleep state of the system. 290 * @dev_state: Target power state of the device. 291 * 292 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power 293 * State Wake) for the device, if present. On failure reset the device's 294 * wakeup.flags.valid flag. 295 * 296 * RETURN VALUE: 297 * 0 if either _DSW or _PSW has been successfully executed 298 * 0 if neither _DSW nor _PSW has been found 299 * -ENODEV if the execution of either _DSW or _PSW has failed 300 */ 301int acpi_device_sleep_wake(struct acpi_device *dev, 302 int enable, int sleep_state, int dev_state) 303{ 304 union acpi_object in_arg[3]; 305 struct acpi_object_list arg_list = { 3, in_arg }; 306 acpi_status status = AE_OK; 307 308 /* 309 * Try to execute _DSW first. 310 * 311 * Three agruments are needed for the _DSW object: 312 * Argument 0: enable/disable the wake capabilities 313 * Argument 1: target system state 314 * Argument 2: target device state 315 * When _DSW object is called to disable the wake capabilities, maybe 316 * the first argument is filled. The values of the other two agruments 317 * are meaningless. 318 */ 319 in_arg[0].type = ACPI_TYPE_INTEGER; 320 in_arg[0].integer.value = enable; 321 in_arg[1].type = ACPI_TYPE_INTEGER; 322 in_arg[1].integer.value = sleep_state; 323 in_arg[2].type = ACPI_TYPE_INTEGER; 324 in_arg[2].integer.value = dev_state; 325 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL); 326 if (ACPI_SUCCESS(status)) { 327 return 0; 328 } else if (status != AE_NOT_FOUND) { 329 printk(KERN_ERR PREFIX "_DSW execution failed\n"); 330 dev->wakeup.flags.valid = 0; 331 return -ENODEV; 332 } 333 334 /* Execute _PSW */ 335 arg_list.count = 1; 336 in_arg[0].integer.value = enable; 337 status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL); 338 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) { 339 printk(KERN_ERR PREFIX "_PSW execution failed\n"); 340 dev->wakeup.flags.valid = 0; 341 return -ENODEV; 342 } 343 344 return 0; 345} 346 347/* 348 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229): 349 * 1. Power on the power resources required for the wakeup device 350 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power 351 * State Wake) for the device, if present 352 */ 353int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state) 354{ 355 int i, err = 0; 356 357 if (!dev || !dev->wakeup.flags.valid) 358 return -EINVAL; 359 360 mutex_lock(&acpi_device_lock); 361 362 if (dev->wakeup.prepare_count++) 363 goto out; 364 365 /* Open power resource */ 366 for (i = 0; i < dev->wakeup.resources.count; i++) { 367 int ret = acpi_power_on(dev->wakeup.resources.handles[i], dev); 368 if (ret) { 369 printk(KERN_ERR PREFIX "Transition power state\n"); 370 dev->wakeup.flags.valid = 0; 371 err = -ENODEV; 372 goto err_out; 373 } 374 } 375 376 /* 377 * Passing 3 as the third argument below means the device may be placed 378 * in arbitrary power state afterwards. 379 */ 380 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3); 381 382 err_out: 383 if (err) 384 dev->wakeup.prepare_count = 0; 385 386 out: 387 mutex_unlock(&acpi_device_lock); 388 return err; 389} 390 391/* 392 * Shutdown a wakeup device, counterpart of above method 393 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power 394 * State Wake) for the device, if present 395 * 2. Shutdown down the power resources 396 */ 397int acpi_disable_wakeup_device_power(struct acpi_device *dev) 398{ 399 int i, err = 0; 400 401 if (!dev || !dev->wakeup.flags.valid) 402 return -EINVAL; 403 404 mutex_lock(&acpi_device_lock); 405 406 if (--dev->wakeup.prepare_count > 0) 407 goto out; 408 409 /* 410 * Executing the code below even if prepare_count is already zero when 411 * the function is called may be useful, for example for initialisation. 412 */ 413 if (dev->wakeup.prepare_count < 0) 414 dev->wakeup.prepare_count = 0; 415 416 err = acpi_device_sleep_wake(dev, 0, 0, 0); 417 if (err) 418 goto out; 419 420 /* Close power resource */ 421 for (i = 0; i < dev->wakeup.resources.count; i++) { 422 int ret = acpi_power_off_device( 423 dev->wakeup.resources.handles[i], dev); 424 if (ret) { 425 printk(KERN_ERR PREFIX "Transition power state\n"); 426 dev->wakeup.flags.valid = 0; 427 err = -ENODEV; 428 goto out; 429 } 430 } 431 432 out: 433 mutex_unlock(&acpi_device_lock); 434 return err; 435} 436 437/* -------------------------------------------------------------------------- 438 Device Power Management 439 -------------------------------------------------------------------------- */ 440 441int acpi_power_get_inferred_state(struct acpi_device *device) 442{ 443 int result = 0; 444 struct acpi_handle_list *list = NULL; 445 int list_state = 0; 446 int i = 0; 447 448 449 if (!device) 450 return -EINVAL; 451 452 device->power.state = ACPI_STATE_UNKNOWN; 453 454 /* 455 * We know a device's inferred power state when all the resources 456 * required for a given D-state are 'on'. 457 */ 458 for (i = ACPI_STATE_D0; i < ACPI_STATE_D3; i++) { 459 list = &device->power.states[i].resources; 460 if (list->count < 1) 461 continue; 462 463 result = acpi_power_get_list_state(list, &list_state); 464 if (result) 465 return result; 466 467 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) { 468 device->power.state = i; 469 return 0; 470 } 471 } 472 473 device->power.state = ACPI_STATE_D3; 474 475 return 0; 476} 477 478int acpi_power_transition(struct acpi_device *device, int state) 479{ 480 int result = 0; 481 struct acpi_handle_list *cl = NULL; /* Current Resources */ 482 struct acpi_handle_list *tl = NULL; /* Target Resources */ 483 int i = 0; 484 485 486 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3)) 487 return -EINVAL; 488 489 if ((device->power.state < ACPI_STATE_D0) 490 || (device->power.state > ACPI_STATE_D3)) 491 return -ENODEV; 492 493 cl = &device->power.states[device->power.state].resources; 494 tl = &device->power.states[state].resources; 495 496 /* TBD: Resources must be ordered. */ 497 498 /* 499 * First we reference all power resources required in the target list 500 * (e.g. so the device doesn't lose power while transitioning). 501 */ 502 for (i = 0; i < tl->count; i++) { 503 result = acpi_power_on(tl->handles[i], device); 504 if (result) 505 goto end; 506 } 507 508 if (device->power.state == state) { 509 goto end; 510 } 511 512 /* 513 * Then we dereference all power resources used in the current list. 514 */ 515 for (i = 0; i < cl->count; i++) { 516 result = acpi_power_off_device(cl->handles[i], device); 517 if (result) 518 goto end; 519 } 520 521 end: 522 if (result) 523 device->power.state = ACPI_STATE_UNKNOWN; 524 else { 525 /* We shouldn't change the state till all above operations succeed */ 526 device->power.state = state; 527 } 528 529 return result; 530} 531 532/* -------------------------------------------------------------------------- 533 Driver Interface 534 -------------------------------------------------------------------------- */ 535 536static int acpi_power_add(struct acpi_device *device) 537{ 538 int result = 0, state; 539 acpi_status status = AE_OK; 540 struct acpi_power_resource *resource = NULL; 541 union acpi_object acpi_object; 542 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object }; 543 544 545 if (!device) 546 return -EINVAL; 547 548 resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL); 549 if (!resource) 550 return -ENOMEM; 551 552 resource->device = device; 553 mutex_init(&resource->resource_lock); 554 INIT_LIST_HEAD(&resource->reference); 555 strcpy(resource->name, device->pnp.bus_id); 556 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME); 557 strcpy(acpi_device_class(device), ACPI_POWER_CLASS); 558 device->driver_data = resource; 559 560 /* Evalute the object to get the system level and resource order. */ 561 status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer); 562 if (ACPI_FAILURE(status)) { 563 result = -ENODEV; 564 goto end; 565 } 566 resource->system_level = acpi_object.power_resource.system_level; 567 resource->order = acpi_object.power_resource.resource_order; 568 569 result = acpi_power_get_state(device->handle, &state); 570 if (result) 571 goto end; 572 573 switch (state) { 574 case ACPI_POWER_RESOURCE_STATE_ON: 575 device->power.state = ACPI_STATE_D0; 576 break; 577 case ACPI_POWER_RESOURCE_STATE_OFF: 578 device->power.state = ACPI_STATE_D3; 579 break; 580 default: 581 device->power.state = ACPI_STATE_UNKNOWN; 582 break; 583 } 584 585 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device), 586 acpi_device_bid(device), state ? "on" : "off"); 587 588 end: 589 if (result) 590 kfree(resource); 591 592 return result; 593} 594 595static int acpi_power_remove(struct acpi_device *device, int type) 596{ 597 struct acpi_power_resource *resource = NULL; 598 struct list_head *node, *next; 599 600 601 if (!device || !acpi_driver_data(device)) 602 return -EINVAL; 603 604 resource = acpi_driver_data(device); 605 606 mutex_lock(&resource->resource_lock); 607 list_for_each_safe(node, next, &resource->reference) { 608 struct acpi_power_reference *ref = container_of(node, struct acpi_power_reference, node); 609 list_del(&ref->node); 610 kfree(ref); 611 } 612 mutex_unlock(&resource->resource_lock); 613 614 kfree(resource); 615 616 return 0; 617} 618 619static int acpi_power_resume(struct acpi_device *device) 620{ 621 int result = 0, state; 622 struct acpi_power_resource *resource = NULL; 623 struct acpi_power_reference *ref; 624 625 if (!device || !acpi_driver_data(device)) 626 return -EINVAL; 627 628 resource = acpi_driver_data(device); 629 630 result = acpi_power_get_state(device->handle, &state); 631 if (result) 632 return result; 633 634 mutex_lock(&resource->resource_lock); 635 if (state == ACPI_POWER_RESOURCE_STATE_OFF && 636 !list_empty(&resource->reference)) { 637 ref = container_of(resource->reference.next, struct acpi_power_reference, node); 638 mutex_unlock(&resource->resource_lock); 639 result = acpi_power_on(device->handle, ref->device); 640 return result; 641 } 642 643 mutex_unlock(&resource->resource_lock); 644 return 0; 645} 646 647int __init acpi_power_init(void) 648{ 649 INIT_LIST_HEAD(&acpi_power_resource_list); 650 return acpi_bus_register_driver(&acpi_power_driver); 651} 652