| 1 | /* |
| 2 | * drivers/acpi/device_pm.c - ACPI device power management routines. |
| 3 | * |
| 4 | * Copyright (C) 2012, Intel Corp. |
| 5 | * Author: Rafael J. Wysocki <rafael.j.wysocki@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 version 2 as published |
| 11 | * by the Free Software Foundation. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, but |
| 14 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * General Public License for more details. |
| 17 | * |
| 18 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 19 | */ |
| 20 | |
| 21 | #include <linux/acpi.h> |
| 22 | #include <linux/export.h> |
| 23 | #include <linux/mutex.h> |
| 24 | #include <linux/pm_qos.h> |
| 25 | #include <linux/pm_domain.h> |
| 26 | #include <linux/pm_runtime.h> |
| 27 | |
| 28 | #include "internal.h" |
| 29 | |
| 30 | #define _COMPONENT ACPI_POWER_COMPONENT |
| 31 | ACPI_MODULE_NAME("device_pm"); |
| 32 | |
| 33 | /** |
| 34 | * acpi_power_state_string - String representation of ACPI device power state. |
| 35 | * @state: ACPI device power state to return the string representation of. |
| 36 | */ |
| 37 | const char *acpi_power_state_string(int state) |
| 38 | { |
| 39 | switch (state) { |
| 40 | case ACPI_STATE_D0: |
| 41 | return "D0"; |
| 42 | case ACPI_STATE_D1: |
| 43 | return "D1"; |
| 44 | case ACPI_STATE_D2: |
| 45 | return "D2"; |
| 46 | case ACPI_STATE_D3_HOT: |
| 47 | return "D3hot"; |
| 48 | case ACPI_STATE_D3_COLD: |
| 49 | return "D3cold"; |
| 50 | default: |
| 51 | return "(unknown)"; |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | /** |
| 56 | * acpi_device_get_power - Get power state of an ACPI device. |
| 57 | * @device: Device to get the power state of. |
| 58 | * @state: Place to store the power state of the device. |
| 59 | * |
| 60 | * This function does not update the device's power.state field, but it may |
| 61 | * update its parent's power.state field (when the parent's power state is |
| 62 | * unknown and the device's power state turns out to be D0). |
| 63 | */ |
| 64 | int acpi_device_get_power(struct acpi_device *device, int *state) |
| 65 | { |
| 66 | int result = ACPI_STATE_UNKNOWN; |
| 67 | |
| 68 | if (!device || !state) |
| 69 | return -EINVAL; |
| 70 | |
| 71 | if (!device->flags.power_manageable) { |
| 72 | /* TBD: Non-recursive algorithm for walking up hierarchy. */ |
| 73 | *state = device->parent ? |
| 74 | device->parent->power.state : ACPI_STATE_D0; |
| 75 | goto out; |
| 76 | } |
| 77 | |
| 78 | /* |
| 79 | * Get the device's power state from power resources settings and _PSC, |
| 80 | * if available. |
| 81 | */ |
| 82 | if (device->power.flags.power_resources) { |
| 83 | int error = acpi_power_get_inferred_state(device, &result); |
| 84 | if (error) |
| 85 | return error; |
| 86 | } |
| 87 | if (device->power.flags.explicit_get) { |
| 88 | acpi_handle handle = device->handle; |
| 89 | unsigned long long psc; |
| 90 | acpi_status status; |
| 91 | |
| 92 | status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc); |
| 93 | if (ACPI_FAILURE(status)) |
| 94 | return -ENODEV; |
| 95 | |
| 96 | /* |
| 97 | * The power resources settings may indicate a power state |
| 98 | * shallower than the actual power state of the device, because |
| 99 | * the same power resources may be referenced by other devices. |
| 100 | * |
| 101 | * For systems predating ACPI 4.0 we assume that D3hot is the |
| 102 | * deepest state that can be supported. |
| 103 | */ |
| 104 | if (psc > result && psc < ACPI_STATE_D3_COLD) |
| 105 | result = psc; |
| 106 | else if (result == ACPI_STATE_UNKNOWN) |
| 107 | result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc; |
| 108 | } |
| 109 | |
| 110 | /* |
| 111 | * If we were unsure about the device parent's power state up to this |
| 112 | * point, the fact that the device is in D0 implies that the parent has |
| 113 | * to be in D0 too, except if ignore_parent is set. |
| 114 | */ |
| 115 | if (!device->power.flags.ignore_parent && device->parent |
| 116 | && device->parent->power.state == ACPI_STATE_UNKNOWN |
| 117 | && result == ACPI_STATE_D0) |
| 118 | device->parent->power.state = ACPI_STATE_D0; |
| 119 | |
| 120 | *state = result; |
| 121 | |
| 122 | out: |
| 123 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n", |
| 124 | device->pnp.bus_id, acpi_power_state_string(*state))); |
| 125 | |
| 126 | return 0; |
| 127 | } |
| 128 | |
| 129 | static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state) |
| 130 | { |
| 131 | if (adev->power.states[state].flags.explicit_set) { |
| 132 | char method[5] = { '_', 'P', 'S', '0' + state, '\0' }; |
| 133 | acpi_status status; |
| 134 | |
| 135 | status = acpi_evaluate_object(adev->handle, method, NULL, NULL); |
| 136 | if (ACPI_FAILURE(status)) |
| 137 | return -ENODEV; |
| 138 | } |
| 139 | return 0; |
| 140 | } |
| 141 | |
| 142 | /** |
| 143 | * acpi_device_set_power - Set power state of an ACPI device. |
| 144 | * @device: Device to set the power state of. |
| 145 | * @state: New power state to set. |
| 146 | * |
| 147 | * Callers must ensure that the device is power manageable before using this |
| 148 | * function. |
| 149 | */ |
| 150 | int acpi_device_set_power(struct acpi_device *device, int state) |
| 151 | { |
| 152 | int target_state = state; |
| 153 | int result = 0; |
| 154 | |
| 155 | if (!device || !device->flags.power_manageable |
| 156 | || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD)) |
| 157 | return -EINVAL; |
| 158 | |
| 159 | /* Make sure this is a valid target state */ |
| 160 | |
| 161 | if (state == device->power.state) { |
| 162 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n", |
| 163 | device->pnp.bus_id, |
| 164 | acpi_power_state_string(state))); |
| 165 | return 0; |
| 166 | } |
| 167 | |
| 168 | if (state == ACPI_STATE_D3_COLD) { |
| 169 | /* |
| 170 | * For transitions to D3cold we need to execute _PS3 and then |
| 171 | * possibly drop references to the power resources in use. |
| 172 | */ |
| 173 | state = ACPI_STATE_D3_HOT; |
| 174 | /* If _PR3 is not available, use D3hot as the target state. */ |
| 175 | if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid) |
| 176 | target_state = state; |
| 177 | } else if (!device->power.states[state].flags.valid) { |
| 178 | dev_warn(&device->dev, "Power state %s not supported\n", |
| 179 | acpi_power_state_string(state)); |
| 180 | return -ENODEV; |
| 181 | } |
| 182 | |
| 183 | if (!device->power.flags.ignore_parent && |
| 184 | device->parent && (state < device->parent->power.state)) { |
| 185 | dev_warn(&device->dev, |
| 186 | "Cannot transition to power state %s for parent in %s\n", |
| 187 | acpi_power_state_string(state), |
| 188 | acpi_power_state_string(device->parent->power.state)); |
| 189 | return -ENODEV; |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * Transition Power |
| 194 | * ---------------- |
| 195 | * In accordance with ACPI 6, _PSx is executed before manipulating power |
| 196 | * resources, unless the target state is D0, in which case _PS0 is |
| 197 | * supposed to be executed after turning the power resources on. |
| 198 | */ |
| 199 | if (state > ACPI_STATE_D0) { |
| 200 | /* |
| 201 | * According to ACPI 6, devices cannot go from lower-power |
| 202 | * (deeper) states to higher-power (shallower) states. |
| 203 | */ |
| 204 | if (state < device->power.state) { |
| 205 | dev_warn(&device->dev, "Cannot transition from %s to %s\n", |
| 206 | acpi_power_state_string(device->power.state), |
| 207 | acpi_power_state_string(state)); |
| 208 | return -ENODEV; |
| 209 | } |
| 210 | |
| 211 | result = acpi_dev_pm_explicit_set(device, state); |
| 212 | if (result) |
| 213 | goto end; |
| 214 | |
| 215 | if (device->power.flags.power_resources) |
| 216 | result = acpi_power_transition(device, target_state); |
| 217 | } else { |
| 218 | if (device->power.flags.power_resources) { |
| 219 | result = acpi_power_transition(device, ACPI_STATE_D0); |
| 220 | if (result) |
| 221 | goto end; |
| 222 | } |
| 223 | result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); |
| 224 | } |
| 225 | |
| 226 | end: |
| 227 | if (result) { |
| 228 | dev_warn(&device->dev, "Failed to change power state to %s\n", |
| 229 | acpi_power_state_string(state)); |
| 230 | } else { |
| 231 | device->power.state = target_state; |
| 232 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, |
| 233 | "Device [%s] transitioned to %s\n", |
| 234 | device->pnp.bus_id, |
| 235 | acpi_power_state_string(state))); |
| 236 | } |
| 237 | |
| 238 | return result; |
| 239 | } |
| 240 | EXPORT_SYMBOL(acpi_device_set_power); |
| 241 | |
| 242 | int acpi_bus_set_power(acpi_handle handle, int state) |
| 243 | { |
| 244 | struct acpi_device *device; |
| 245 | int result; |
| 246 | |
| 247 | result = acpi_bus_get_device(handle, &device); |
| 248 | if (result) |
| 249 | return result; |
| 250 | |
| 251 | return acpi_device_set_power(device, state); |
| 252 | } |
| 253 | EXPORT_SYMBOL(acpi_bus_set_power); |
| 254 | |
| 255 | int acpi_bus_init_power(struct acpi_device *device) |
| 256 | { |
| 257 | int state; |
| 258 | int result; |
| 259 | |
| 260 | if (!device) |
| 261 | return -EINVAL; |
| 262 | |
| 263 | device->power.state = ACPI_STATE_UNKNOWN; |
| 264 | if (!acpi_device_is_present(device)) |
| 265 | return -ENXIO; |
| 266 | |
| 267 | result = acpi_device_get_power(device, &state); |
| 268 | if (result) |
| 269 | return result; |
| 270 | |
| 271 | if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) { |
| 272 | /* Reference count the power resources. */ |
| 273 | result = acpi_power_on_resources(device, state); |
| 274 | if (result) |
| 275 | return result; |
| 276 | |
| 277 | if (state == ACPI_STATE_D0) { |
| 278 | /* |
| 279 | * If _PSC is not present and the state inferred from |
| 280 | * power resources appears to be D0, it still may be |
| 281 | * necessary to execute _PS0 at this point, because |
| 282 | * another device using the same power resources may |
| 283 | * have been put into D0 previously and that's why we |
| 284 | * see D0 here. |
| 285 | */ |
| 286 | result = acpi_dev_pm_explicit_set(device, state); |
| 287 | if (result) |
| 288 | return result; |
| 289 | } |
| 290 | } else if (state == ACPI_STATE_UNKNOWN) { |
| 291 | /* |
| 292 | * No power resources and missing _PSC? Cross fingers and make |
| 293 | * it D0 in hope that this is what the BIOS put the device into. |
| 294 | * [We tried to force D0 here by executing _PS0, but that broke |
| 295 | * Toshiba P870-303 in a nasty way.] |
| 296 | */ |
| 297 | state = ACPI_STATE_D0; |
| 298 | } |
| 299 | device->power.state = state; |
| 300 | return 0; |
| 301 | } |
| 302 | |
| 303 | /** |
| 304 | * acpi_device_fix_up_power - Force device with missing _PSC into D0. |
| 305 | * @device: Device object whose power state is to be fixed up. |
| 306 | * |
| 307 | * Devices without power resources and _PSC, but having _PS0 and _PS3 defined, |
| 308 | * are assumed to be put into D0 by the BIOS. However, in some cases that may |
| 309 | * not be the case and this function should be used then. |
| 310 | */ |
| 311 | int acpi_device_fix_up_power(struct acpi_device *device) |
| 312 | { |
| 313 | int ret = 0; |
| 314 | |
| 315 | if (!device->power.flags.power_resources |
| 316 | && !device->power.flags.explicit_get |
| 317 | && device->power.state == ACPI_STATE_D0) |
| 318 | ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0); |
| 319 | |
| 320 | return ret; |
| 321 | } |
| 322 | EXPORT_SYMBOL_GPL(acpi_device_fix_up_power); |
| 323 | |
| 324 | int acpi_device_update_power(struct acpi_device *device, int *state_p) |
| 325 | { |
| 326 | int state; |
| 327 | int result; |
| 328 | |
| 329 | if (device->power.state == ACPI_STATE_UNKNOWN) { |
| 330 | result = acpi_bus_init_power(device); |
| 331 | if (!result && state_p) |
| 332 | *state_p = device->power.state; |
| 333 | |
| 334 | return result; |
| 335 | } |
| 336 | |
| 337 | result = acpi_device_get_power(device, &state); |
| 338 | if (result) |
| 339 | return result; |
| 340 | |
| 341 | if (state == ACPI_STATE_UNKNOWN) { |
| 342 | state = ACPI_STATE_D0; |
| 343 | result = acpi_device_set_power(device, state); |
| 344 | if (result) |
| 345 | return result; |
| 346 | } else { |
| 347 | if (device->power.flags.power_resources) { |
| 348 | /* |
| 349 | * We don't need to really switch the state, bu we need |
| 350 | * to update the power resources' reference counters. |
| 351 | */ |
| 352 | result = acpi_power_transition(device, state); |
| 353 | if (result) |
| 354 | return result; |
| 355 | } |
| 356 | device->power.state = state; |
| 357 | } |
| 358 | if (state_p) |
| 359 | *state_p = state; |
| 360 | |
| 361 | return 0; |
| 362 | } |
| 363 | EXPORT_SYMBOL_GPL(acpi_device_update_power); |
| 364 | |
| 365 | int acpi_bus_update_power(acpi_handle handle, int *state_p) |
| 366 | { |
| 367 | struct acpi_device *device; |
| 368 | int result; |
| 369 | |
| 370 | result = acpi_bus_get_device(handle, &device); |
| 371 | return result ? result : acpi_device_update_power(device, state_p); |
| 372 | } |
| 373 | EXPORT_SYMBOL_GPL(acpi_bus_update_power); |
| 374 | |
| 375 | bool acpi_bus_power_manageable(acpi_handle handle) |
| 376 | { |
| 377 | struct acpi_device *device; |
| 378 | int result; |
| 379 | |
| 380 | result = acpi_bus_get_device(handle, &device); |
| 381 | return result ? false : device->flags.power_manageable; |
| 382 | } |
| 383 | EXPORT_SYMBOL(acpi_bus_power_manageable); |
| 384 | |
| 385 | #ifdef CONFIG_PM |
| 386 | static DEFINE_MUTEX(acpi_pm_notifier_lock); |
| 387 | |
| 388 | static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used) |
| 389 | { |
| 390 | struct acpi_device *adev; |
| 391 | |
| 392 | if (val != ACPI_NOTIFY_DEVICE_WAKE) |
| 393 | return; |
| 394 | |
| 395 | adev = acpi_bus_get_acpi_device(handle); |
| 396 | if (!adev) |
| 397 | return; |
| 398 | |
| 399 | mutex_lock(&acpi_pm_notifier_lock); |
| 400 | |
| 401 | if (adev->wakeup.flags.notifier_present) { |
| 402 | __pm_wakeup_event(adev->wakeup.ws, 0); |
| 403 | if (adev->wakeup.context.func) |
| 404 | adev->wakeup.context.func(&adev->wakeup.context); |
| 405 | } |
| 406 | |
| 407 | mutex_unlock(&acpi_pm_notifier_lock); |
| 408 | |
| 409 | acpi_bus_put_acpi_device(adev); |
| 410 | } |
| 411 | |
| 412 | /** |
| 413 | * acpi_add_pm_notifier - Register PM notify handler for given ACPI device. |
| 414 | * @adev: ACPI device to add the notify handler for. |
| 415 | * @dev: Device to generate a wakeup event for while handling the notification. |
| 416 | * @func: Work function to execute when handling the notification. |
| 417 | * |
| 418 | * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of |
| 419 | * PM wakeup events. For example, wakeup events may be generated for bridges |
| 420 | * if one of the devices below the bridge is signaling wakeup, even if the |
| 421 | * bridge itself doesn't have a wakeup GPE associated with it. |
| 422 | */ |
| 423 | acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev, |
| 424 | void (*func)(struct acpi_device_wakeup_context *context)) |
| 425 | { |
| 426 | acpi_status status = AE_ALREADY_EXISTS; |
| 427 | |
| 428 | if (!dev && !func) |
| 429 | return AE_BAD_PARAMETER; |
| 430 | |
| 431 | mutex_lock(&acpi_pm_notifier_lock); |
| 432 | |
| 433 | if (adev->wakeup.flags.notifier_present) |
| 434 | goto out; |
| 435 | |
| 436 | adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev)); |
| 437 | adev->wakeup.context.dev = dev; |
| 438 | adev->wakeup.context.func = func; |
| 439 | |
| 440 | status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY, |
| 441 | acpi_pm_notify_handler, NULL); |
| 442 | if (ACPI_FAILURE(status)) |
| 443 | goto out; |
| 444 | |
| 445 | adev->wakeup.flags.notifier_present = true; |
| 446 | |
| 447 | out: |
| 448 | mutex_unlock(&acpi_pm_notifier_lock); |
| 449 | return status; |
| 450 | } |
| 451 | |
| 452 | /** |
| 453 | * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device. |
| 454 | * @adev: ACPI device to remove the notifier from. |
| 455 | */ |
| 456 | acpi_status acpi_remove_pm_notifier(struct acpi_device *adev) |
| 457 | { |
| 458 | acpi_status status = AE_BAD_PARAMETER; |
| 459 | |
| 460 | mutex_lock(&acpi_pm_notifier_lock); |
| 461 | |
| 462 | if (!adev->wakeup.flags.notifier_present) |
| 463 | goto out; |
| 464 | |
| 465 | status = acpi_remove_notify_handler(adev->handle, |
| 466 | ACPI_SYSTEM_NOTIFY, |
| 467 | acpi_pm_notify_handler); |
| 468 | if (ACPI_FAILURE(status)) |
| 469 | goto out; |
| 470 | |
| 471 | adev->wakeup.context.func = NULL; |
| 472 | adev->wakeup.context.dev = NULL; |
| 473 | wakeup_source_unregister(adev->wakeup.ws); |
| 474 | |
| 475 | adev->wakeup.flags.notifier_present = false; |
| 476 | |
| 477 | out: |
| 478 | mutex_unlock(&acpi_pm_notifier_lock); |
| 479 | return status; |
| 480 | } |
| 481 | |
| 482 | bool acpi_bus_can_wakeup(acpi_handle handle) |
| 483 | { |
| 484 | struct acpi_device *device; |
| 485 | int result; |
| 486 | |
| 487 | result = acpi_bus_get_device(handle, &device); |
| 488 | return result ? false : device->wakeup.flags.valid; |
| 489 | } |
| 490 | EXPORT_SYMBOL(acpi_bus_can_wakeup); |
| 491 | |
| 492 | /** |
| 493 | * acpi_dev_pm_get_state - Get preferred power state of ACPI device. |
| 494 | * @dev: Device whose preferred target power state to return. |
| 495 | * @adev: ACPI device node corresponding to @dev. |
| 496 | * @target_state: System state to match the resultant device state. |
| 497 | * @d_min_p: Location to store the highest power state available to the device. |
| 498 | * @d_max_p: Location to store the lowest power state available to the device. |
| 499 | * |
| 500 | * Find the lowest power (highest number) and highest power (lowest number) ACPI |
| 501 | * device power states that the device can be in while the system is in the |
| 502 | * state represented by @target_state. Store the integer numbers representing |
| 503 | * those stats in the memory locations pointed to by @d_max_p and @d_min_p, |
| 504 | * respectively. |
| 505 | * |
| 506 | * Callers must ensure that @dev and @adev are valid pointers and that @adev |
| 507 | * actually corresponds to @dev before using this function. |
| 508 | * |
| 509 | * Returns 0 on success or -ENODATA when one of the ACPI methods fails or |
| 510 | * returns a value that doesn't make sense. The memory locations pointed to by |
| 511 | * @d_max_p and @d_min_p are only modified on success. |
| 512 | */ |
| 513 | static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, |
| 514 | u32 target_state, int *d_min_p, int *d_max_p) |
| 515 | { |
| 516 | char method[] = { '_', 'S', '0' + target_state, 'D', '\0' }; |
| 517 | acpi_handle handle = adev->handle; |
| 518 | unsigned long long ret; |
| 519 | int d_min, d_max; |
| 520 | bool wakeup = false; |
| 521 | acpi_status status; |
| 522 | |
| 523 | /* |
| 524 | * If the system state is S0, the lowest power state the device can be |
| 525 | * in is D3cold, unless the device has _S0W and is supposed to signal |
| 526 | * wakeup, in which case the return value of _S0W has to be used as the |
| 527 | * lowest power state available to the device. |
| 528 | */ |
| 529 | d_min = ACPI_STATE_D0; |
| 530 | d_max = ACPI_STATE_D3_COLD; |
| 531 | |
| 532 | /* |
| 533 | * If present, _SxD methods return the minimum D-state (highest power |
| 534 | * state) we can use for the corresponding S-states. Otherwise, the |
| 535 | * minimum D-state is D0 (ACPI 3.x). |
| 536 | */ |
| 537 | if (target_state > ACPI_STATE_S0) { |
| 538 | /* |
| 539 | * We rely on acpi_evaluate_integer() not clobbering the integer |
| 540 | * provided if AE_NOT_FOUND is returned. |
| 541 | */ |
| 542 | ret = d_min; |
| 543 | status = acpi_evaluate_integer(handle, method, NULL, &ret); |
| 544 | if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND) |
| 545 | || ret > ACPI_STATE_D3_COLD) |
| 546 | return -ENODATA; |
| 547 | |
| 548 | /* |
| 549 | * We need to handle legacy systems where D3hot and D3cold are |
| 550 | * the same and 3 is returned in both cases, so fall back to |
| 551 | * D3cold if D3hot is not a valid state. |
| 552 | */ |
| 553 | if (!adev->power.states[ret].flags.valid) { |
| 554 | if (ret == ACPI_STATE_D3_HOT) |
| 555 | ret = ACPI_STATE_D3_COLD; |
| 556 | else |
| 557 | return -ENODATA; |
| 558 | } |
| 559 | d_min = ret; |
| 560 | wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid |
| 561 | && adev->wakeup.sleep_state >= target_state; |
| 562 | } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) != |
| 563 | PM_QOS_FLAGS_NONE) { |
| 564 | wakeup = adev->wakeup.flags.valid; |
| 565 | } |
| 566 | |
| 567 | /* |
| 568 | * If _PRW says we can wake up the system from the target sleep state, |
| 569 | * the D-state returned by _SxD is sufficient for that (we assume a |
| 570 | * wakeup-aware driver if wake is set). Still, if _SxW exists |
| 571 | * (ACPI 3.x), it should return the maximum (lowest power) D-state that |
| 572 | * can wake the system. _S0W may be valid, too. |
| 573 | */ |
| 574 | if (wakeup) { |
| 575 | method[3] = 'W'; |
| 576 | status = acpi_evaluate_integer(handle, method, NULL, &ret); |
| 577 | if (status == AE_NOT_FOUND) { |
| 578 | if (target_state > ACPI_STATE_S0) |
| 579 | d_max = d_min; |
| 580 | } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) { |
| 581 | /* Fall back to D3cold if ret is not a valid state. */ |
| 582 | if (!adev->power.states[ret].flags.valid) |
| 583 | ret = ACPI_STATE_D3_COLD; |
| 584 | |
| 585 | d_max = ret > d_min ? ret : d_min; |
| 586 | } else { |
| 587 | return -ENODATA; |
| 588 | } |
| 589 | } |
| 590 | |
| 591 | if (d_min_p) |
| 592 | *d_min_p = d_min; |
| 593 | |
| 594 | if (d_max_p) |
| 595 | *d_max_p = d_max; |
| 596 | |
| 597 | return 0; |
| 598 | } |
| 599 | |
| 600 | /** |
| 601 | * acpi_pm_device_sleep_state - Get preferred power state of ACPI device. |
| 602 | * @dev: Device whose preferred target power state to return. |
| 603 | * @d_min_p: Location to store the upper limit of the allowed states range. |
| 604 | * @d_max_in: Deepest low-power state to take into consideration. |
| 605 | * Return value: Preferred power state of the device on success, -ENODEV |
| 606 | * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is |
| 607 | * incorrect, or -ENODATA on ACPI method failure. |
| 608 | * |
| 609 | * The caller must ensure that @dev is valid before using this function. |
| 610 | */ |
| 611 | int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in) |
| 612 | { |
| 613 | struct acpi_device *adev; |
| 614 | int ret, d_min, d_max; |
| 615 | |
| 616 | if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD) |
| 617 | return -EINVAL; |
| 618 | |
| 619 | if (d_max_in > ACPI_STATE_D2) { |
| 620 | enum pm_qos_flags_status stat; |
| 621 | |
| 622 | stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF); |
| 623 | if (stat == PM_QOS_FLAGS_ALL) |
| 624 | d_max_in = ACPI_STATE_D2; |
| 625 | } |
| 626 | |
| 627 | adev = ACPI_COMPANION(dev); |
| 628 | if (!adev) { |
| 629 | dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); |
| 630 | return -ENODEV; |
| 631 | } |
| 632 | |
| 633 | ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(), |
| 634 | &d_min, &d_max); |
| 635 | if (ret) |
| 636 | return ret; |
| 637 | |
| 638 | if (d_max_in < d_min) |
| 639 | return -EINVAL; |
| 640 | |
| 641 | if (d_max > d_max_in) { |
| 642 | for (d_max = d_max_in; d_max > d_min; d_max--) { |
| 643 | if (adev->power.states[d_max].flags.valid) |
| 644 | break; |
| 645 | } |
| 646 | } |
| 647 | |
| 648 | if (d_min_p) |
| 649 | *d_min_p = d_min; |
| 650 | |
| 651 | return d_max; |
| 652 | } |
| 653 | EXPORT_SYMBOL(acpi_pm_device_sleep_state); |
| 654 | |
| 655 | /** |
| 656 | * acpi_pm_notify_work_func - ACPI devices wakeup notification work function. |
| 657 | * @context: Device wakeup context. |
| 658 | */ |
| 659 | static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context) |
| 660 | { |
| 661 | struct device *dev = context->dev; |
| 662 | |
| 663 | if (dev) { |
| 664 | pm_wakeup_event(dev, 0); |
| 665 | pm_request_resume(dev); |
| 666 | } |
| 667 | } |
| 668 | |
| 669 | /** |
| 670 | * acpi_device_wakeup - Enable/disable wakeup functionality for device. |
| 671 | * @adev: ACPI device to enable/disable wakeup functionality for. |
| 672 | * @target_state: State the system is transitioning into. |
| 673 | * @enable: Whether to enable or disable the wakeup functionality. |
| 674 | * |
| 675 | * Enable/disable the GPE associated with @adev so that it can generate |
| 676 | * wakeup signals for the device in response to external (remote) events and |
| 677 | * enable/disable device wakeup power. |
| 678 | * |
| 679 | * Callers must ensure that @adev is a valid ACPI device node before executing |
| 680 | * this function. |
| 681 | */ |
| 682 | static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state, |
| 683 | bool enable) |
| 684 | { |
| 685 | struct acpi_device_wakeup *wakeup = &adev->wakeup; |
| 686 | |
| 687 | if (enable) { |
| 688 | acpi_status res; |
| 689 | int error; |
| 690 | |
| 691 | if (adev->wakeup.flags.enabled) |
| 692 | return 0; |
| 693 | |
| 694 | error = acpi_enable_wakeup_device_power(adev, target_state); |
| 695 | if (error) |
| 696 | return error; |
| 697 | |
| 698 | res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number); |
| 699 | if (ACPI_FAILURE(res)) { |
| 700 | acpi_disable_wakeup_device_power(adev); |
| 701 | return -EIO; |
| 702 | } |
| 703 | adev->wakeup.flags.enabled = 1; |
| 704 | } else if (adev->wakeup.flags.enabled) { |
| 705 | acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number); |
| 706 | acpi_disable_wakeup_device_power(adev); |
| 707 | adev->wakeup.flags.enabled = 0; |
| 708 | } |
| 709 | return 0; |
| 710 | } |
| 711 | |
| 712 | /** |
| 713 | * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device. |
| 714 | * @dev: Device to enable/disable the platform to wake up. |
| 715 | * @enable: Whether to enable or disable the wakeup functionality. |
| 716 | */ |
| 717 | int acpi_pm_device_run_wake(struct device *phys_dev, bool enable) |
| 718 | { |
| 719 | struct acpi_device *adev; |
| 720 | |
| 721 | if (!device_run_wake(phys_dev)) |
| 722 | return -EINVAL; |
| 723 | |
| 724 | adev = ACPI_COMPANION(phys_dev); |
| 725 | if (!adev) { |
| 726 | dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__); |
| 727 | return -ENODEV; |
| 728 | } |
| 729 | |
| 730 | return acpi_device_wakeup(adev, ACPI_STATE_S0, enable); |
| 731 | } |
| 732 | EXPORT_SYMBOL(acpi_pm_device_run_wake); |
| 733 | |
| 734 | #ifdef CONFIG_PM_SLEEP |
| 735 | /** |
| 736 | * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system. |
| 737 | * @dev: Device to enable/desible to wake up the system from sleep states. |
| 738 | * @enable: Whether to enable or disable @dev to wake up the system. |
| 739 | */ |
| 740 | int acpi_pm_device_sleep_wake(struct device *dev, bool enable) |
| 741 | { |
| 742 | struct acpi_device *adev; |
| 743 | int error; |
| 744 | |
| 745 | if (!device_can_wakeup(dev)) |
| 746 | return -EINVAL; |
| 747 | |
| 748 | adev = ACPI_COMPANION(dev); |
| 749 | if (!adev) { |
| 750 | dev_dbg(dev, "ACPI companion missing in %s!\n", __func__); |
| 751 | return -ENODEV; |
| 752 | } |
| 753 | |
| 754 | error = acpi_device_wakeup(adev, acpi_target_system_state(), enable); |
| 755 | if (!error) |
| 756 | dev_dbg(dev, "System wakeup %s by ACPI\n", |
| 757 | enable ? "enabled" : "disabled"); |
| 758 | |
| 759 | return error; |
| 760 | } |
| 761 | #endif /* CONFIG_PM_SLEEP */ |
| 762 | |
| 763 | /** |
| 764 | * acpi_dev_pm_low_power - Put ACPI device into a low-power state. |
| 765 | * @dev: Device to put into a low-power state. |
| 766 | * @adev: ACPI device node corresponding to @dev. |
| 767 | * @system_state: System state to choose the device state for. |
| 768 | */ |
| 769 | static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev, |
| 770 | u32 system_state) |
| 771 | { |
| 772 | int ret, state; |
| 773 | |
| 774 | if (!acpi_device_power_manageable(adev)) |
| 775 | return 0; |
| 776 | |
| 777 | ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state); |
| 778 | return ret ? ret : acpi_device_set_power(adev, state); |
| 779 | } |
| 780 | |
| 781 | /** |
| 782 | * acpi_dev_pm_full_power - Put ACPI device into the full-power state. |
| 783 | * @adev: ACPI device node to put into the full-power state. |
| 784 | */ |
| 785 | static int acpi_dev_pm_full_power(struct acpi_device *adev) |
| 786 | { |
| 787 | return acpi_device_power_manageable(adev) ? |
| 788 | acpi_device_set_power(adev, ACPI_STATE_D0) : 0; |
| 789 | } |
| 790 | |
| 791 | /** |
| 792 | * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI. |
| 793 | * @dev: Device to put into a low-power state. |
| 794 | * |
| 795 | * Put the given device into a runtime low-power state using the standard ACPI |
| 796 | * mechanism. Set up remote wakeup if desired, choose the state to put the |
| 797 | * device into (this checks if remote wakeup is expected to work too), and set |
| 798 | * the power state of the device. |
| 799 | */ |
| 800 | int acpi_dev_runtime_suspend(struct device *dev) |
| 801 | { |
| 802 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 803 | bool remote_wakeup; |
| 804 | int error; |
| 805 | |
| 806 | if (!adev) |
| 807 | return 0; |
| 808 | |
| 809 | remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) > |
| 810 | PM_QOS_FLAGS_NONE; |
| 811 | error = acpi_device_wakeup(adev, ACPI_STATE_S0, remote_wakeup); |
| 812 | if (remote_wakeup && error) |
| 813 | return -EAGAIN; |
| 814 | |
| 815 | error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); |
| 816 | if (error) |
| 817 | acpi_device_wakeup(adev, ACPI_STATE_S0, false); |
| 818 | |
| 819 | return error; |
| 820 | } |
| 821 | EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend); |
| 822 | |
| 823 | /** |
| 824 | * acpi_dev_runtime_resume - Put device into the full-power state using ACPI. |
| 825 | * @dev: Device to put into the full-power state. |
| 826 | * |
| 827 | * Put the given device into the full-power state using the standard ACPI |
| 828 | * mechanism at run time. Set the power state of the device to ACPI D0 and |
| 829 | * disable remote wakeup. |
| 830 | */ |
| 831 | int acpi_dev_runtime_resume(struct device *dev) |
| 832 | { |
| 833 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 834 | int error; |
| 835 | |
| 836 | if (!adev) |
| 837 | return 0; |
| 838 | |
| 839 | error = acpi_dev_pm_full_power(adev); |
| 840 | acpi_device_wakeup(adev, ACPI_STATE_S0, false); |
| 841 | return error; |
| 842 | } |
| 843 | EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume); |
| 844 | |
| 845 | /** |
| 846 | * acpi_subsys_runtime_suspend - Suspend device using ACPI. |
| 847 | * @dev: Device to suspend. |
| 848 | * |
| 849 | * Carry out the generic runtime suspend procedure for @dev and use ACPI to put |
| 850 | * it into a runtime low-power state. |
| 851 | */ |
| 852 | int acpi_subsys_runtime_suspend(struct device *dev) |
| 853 | { |
| 854 | int ret = pm_generic_runtime_suspend(dev); |
| 855 | return ret ? ret : acpi_dev_runtime_suspend(dev); |
| 856 | } |
| 857 | EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend); |
| 858 | |
| 859 | /** |
| 860 | * acpi_subsys_runtime_resume - Resume device using ACPI. |
| 861 | * @dev: Device to Resume. |
| 862 | * |
| 863 | * Use ACPI to put the given device into the full-power state and carry out the |
| 864 | * generic runtime resume procedure for it. |
| 865 | */ |
| 866 | int acpi_subsys_runtime_resume(struct device *dev) |
| 867 | { |
| 868 | int ret = acpi_dev_runtime_resume(dev); |
| 869 | return ret ? ret : pm_generic_runtime_resume(dev); |
| 870 | } |
| 871 | EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume); |
| 872 | |
| 873 | #ifdef CONFIG_PM_SLEEP |
| 874 | /** |
| 875 | * acpi_dev_suspend_late - Put device into a low-power state using ACPI. |
| 876 | * @dev: Device to put into a low-power state. |
| 877 | * |
| 878 | * Put the given device into a low-power state during system transition to a |
| 879 | * sleep state using the standard ACPI mechanism. Set up system wakeup if |
| 880 | * desired, choose the state to put the device into (this checks if system |
| 881 | * wakeup is expected to work too), and set the power state of the device. |
| 882 | */ |
| 883 | int acpi_dev_suspend_late(struct device *dev) |
| 884 | { |
| 885 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 886 | u32 target_state; |
| 887 | bool wakeup; |
| 888 | int error; |
| 889 | |
| 890 | if (!adev) |
| 891 | return 0; |
| 892 | |
| 893 | target_state = acpi_target_system_state(); |
| 894 | wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev); |
| 895 | error = acpi_device_wakeup(adev, target_state, wakeup); |
| 896 | if (wakeup && error) |
| 897 | return error; |
| 898 | |
| 899 | error = acpi_dev_pm_low_power(dev, adev, target_state); |
| 900 | if (error) |
| 901 | acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false); |
| 902 | |
| 903 | return error; |
| 904 | } |
| 905 | EXPORT_SYMBOL_GPL(acpi_dev_suspend_late); |
| 906 | |
| 907 | /** |
| 908 | * acpi_dev_resume_early - Put device into the full-power state using ACPI. |
| 909 | * @dev: Device to put into the full-power state. |
| 910 | * |
| 911 | * Put the given device into the full-power state using the standard ACPI |
| 912 | * mechanism during system transition to the working state. Set the power |
| 913 | * state of the device to ACPI D0 and disable remote wakeup. |
| 914 | */ |
| 915 | int acpi_dev_resume_early(struct device *dev) |
| 916 | { |
| 917 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 918 | int error; |
| 919 | |
| 920 | if (!adev) |
| 921 | return 0; |
| 922 | |
| 923 | error = acpi_dev_pm_full_power(adev); |
| 924 | acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false); |
| 925 | return error; |
| 926 | } |
| 927 | EXPORT_SYMBOL_GPL(acpi_dev_resume_early); |
| 928 | |
| 929 | /** |
| 930 | * acpi_subsys_prepare - Prepare device for system transition to a sleep state. |
| 931 | * @dev: Device to prepare. |
| 932 | */ |
| 933 | int acpi_subsys_prepare(struct device *dev) |
| 934 | { |
| 935 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 936 | u32 sys_target; |
| 937 | int ret, state; |
| 938 | |
| 939 | ret = pm_generic_prepare(dev); |
| 940 | if (ret < 0) |
| 941 | return ret; |
| 942 | |
| 943 | if (!adev || !pm_runtime_suspended(dev) |
| 944 | || device_may_wakeup(dev) != !!adev->wakeup.prepare_count) |
| 945 | return 0; |
| 946 | |
| 947 | sys_target = acpi_target_system_state(); |
| 948 | if (sys_target == ACPI_STATE_S0) |
| 949 | return 1; |
| 950 | |
| 951 | if (adev->power.flags.dsw_present) |
| 952 | return 0; |
| 953 | |
| 954 | ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state); |
| 955 | return !ret && state == adev->power.state; |
| 956 | } |
| 957 | EXPORT_SYMBOL_GPL(acpi_subsys_prepare); |
| 958 | |
| 959 | /** |
| 960 | * acpi_subsys_suspend - Run the device driver's suspend callback. |
| 961 | * @dev: Device to handle. |
| 962 | * |
| 963 | * Follow PCI and resume devices suspended at run time before running their |
| 964 | * system suspend callbacks. |
| 965 | */ |
| 966 | int acpi_subsys_suspend(struct device *dev) |
| 967 | { |
| 968 | pm_runtime_resume(dev); |
| 969 | return pm_generic_suspend(dev); |
| 970 | } |
| 971 | EXPORT_SYMBOL_GPL(acpi_subsys_suspend); |
| 972 | |
| 973 | /** |
| 974 | * acpi_subsys_suspend_late - Suspend device using ACPI. |
| 975 | * @dev: Device to suspend. |
| 976 | * |
| 977 | * Carry out the generic late suspend procedure for @dev and use ACPI to put |
| 978 | * it into a low-power state during system transition into a sleep state. |
| 979 | */ |
| 980 | int acpi_subsys_suspend_late(struct device *dev) |
| 981 | { |
| 982 | int ret = pm_generic_suspend_late(dev); |
| 983 | return ret ? ret : acpi_dev_suspend_late(dev); |
| 984 | } |
| 985 | EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late); |
| 986 | |
| 987 | /** |
| 988 | * acpi_subsys_resume_early - Resume device using ACPI. |
| 989 | * @dev: Device to Resume. |
| 990 | * |
| 991 | * Use ACPI to put the given device into the full-power state and carry out the |
| 992 | * generic early resume procedure for it during system transition into the |
| 993 | * working state. |
| 994 | */ |
| 995 | int acpi_subsys_resume_early(struct device *dev) |
| 996 | { |
| 997 | int ret = acpi_dev_resume_early(dev); |
| 998 | return ret ? ret : pm_generic_resume_early(dev); |
| 999 | } |
| 1000 | EXPORT_SYMBOL_GPL(acpi_subsys_resume_early); |
| 1001 | |
| 1002 | /** |
| 1003 | * acpi_subsys_freeze - Run the device driver's freeze callback. |
| 1004 | * @dev: Device to handle. |
| 1005 | */ |
| 1006 | int acpi_subsys_freeze(struct device *dev) |
| 1007 | { |
| 1008 | /* |
| 1009 | * This used to be done in acpi_subsys_prepare() for all devices and |
| 1010 | * some drivers may depend on it, so do it here. Ideally, however, |
| 1011 | * runtime-suspended devices should not be touched during freeze/thaw |
| 1012 | * transitions. |
| 1013 | */ |
| 1014 | pm_runtime_resume(dev); |
| 1015 | return pm_generic_freeze(dev); |
| 1016 | } |
| 1017 | EXPORT_SYMBOL_GPL(acpi_subsys_freeze); |
| 1018 | |
| 1019 | #endif /* CONFIG_PM_SLEEP */ |
| 1020 | |
| 1021 | static struct dev_pm_domain acpi_general_pm_domain = { |
| 1022 | .ops = { |
| 1023 | .runtime_suspend = acpi_subsys_runtime_suspend, |
| 1024 | .runtime_resume = acpi_subsys_runtime_resume, |
| 1025 | #ifdef CONFIG_PM_SLEEP |
| 1026 | .prepare = acpi_subsys_prepare, |
| 1027 | .complete = pm_complete_with_resume_check, |
| 1028 | .suspend = acpi_subsys_suspend, |
| 1029 | .suspend_late = acpi_subsys_suspend_late, |
| 1030 | .resume_early = acpi_subsys_resume_early, |
| 1031 | .freeze = acpi_subsys_freeze, |
| 1032 | .poweroff = acpi_subsys_suspend, |
| 1033 | .poweroff_late = acpi_subsys_suspend_late, |
| 1034 | .restore_early = acpi_subsys_resume_early, |
| 1035 | #endif |
| 1036 | }, |
| 1037 | }; |
| 1038 | |
| 1039 | /** |
| 1040 | * acpi_dev_pm_detach - Remove ACPI power management from the device. |
| 1041 | * @dev: Device to take care of. |
| 1042 | * @power_off: Whether or not to try to remove power from the device. |
| 1043 | * |
| 1044 | * Remove the device from the general ACPI PM domain and remove its wakeup |
| 1045 | * notifier. If @power_off is set, additionally remove power from the device if |
| 1046 | * possible. |
| 1047 | * |
| 1048 | * Callers must ensure proper synchronization of this function with power |
| 1049 | * management callbacks. |
| 1050 | */ |
| 1051 | static void acpi_dev_pm_detach(struct device *dev, bool power_off) |
| 1052 | { |
| 1053 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 1054 | |
| 1055 | if (adev && dev->pm_domain == &acpi_general_pm_domain) { |
| 1056 | dev_pm_domain_set(dev, NULL); |
| 1057 | acpi_remove_pm_notifier(adev); |
| 1058 | if (power_off) { |
| 1059 | /* |
| 1060 | * If the device's PM QoS resume latency limit or flags |
| 1061 | * have been exposed to user space, they have to be |
| 1062 | * hidden at this point, so that they don't affect the |
| 1063 | * choice of the low-power state to put the device into. |
| 1064 | */ |
| 1065 | dev_pm_qos_hide_latency_limit(dev); |
| 1066 | dev_pm_qos_hide_flags(dev); |
| 1067 | acpi_device_wakeup(adev, ACPI_STATE_S0, false); |
| 1068 | acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0); |
| 1069 | } |
| 1070 | } |
| 1071 | } |
| 1072 | |
| 1073 | /** |
| 1074 | * acpi_dev_pm_attach - Prepare device for ACPI power management. |
| 1075 | * @dev: Device to prepare. |
| 1076 | * @power_on: Whether or not to power on the device. |
| 1077 | * |
| 1078 | * If @dev has a valid ACPI handle that has a valid struct acpi_device object |
| 1079 | * attached to it, install a wakeup notification handler for the device and |
| 1080 | * add it to the general ACPI PM domain. If @power_on is set, the device will |
| 1081 | * be put into the ACPI D0 state before the function returns. |
| 1082 | * |
| 1083 | * This assumes that the @dev's bus type uses generic power management callbacks |
| 1084 | * (or doesn't use any power management callbacks at all). |
| 1085 | * |
| 1086 | * Callers must ensure proper synchronization of this function with power |
| 1087 | * management callbacks. |
| 1088 | */ |
| 1089 | int acpi_dev_pm_attach(struct device *dev, bool power_on) |
| 1090 | { |
| 1091 | struct acpi_device *adev = ACPI_COMPANION(dev); |
| 1092 | |
| 1093 | if (!adev) |
| 1094 | return -ENODEV; |
| 1095 | |
| 1096 | if (dev->pm_domain) |
| 1097 | return -EEXIST; |
| 1098 | |
| 1099 | /* |
| 1100 | * Only attach the power domain to the first device if the |
| 1101 | * companion is shared by multiple. This is to prevent doing power |
| 1102 | * management twice. |
| 1103 | */ |
| 1104 | if (!acpi_device_is_first_physical_node(adev, dev)) |
| 1105 | return -EBUSY; |
| 1106 | |
| 1107 | acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func); |
| 1108 | dev_pm_domain_set(dev, &acpi_general_pm_domain); |
| 1109 | if (power_on) { |
| 1110 | acpi_dev_pm_full_power(adev); |
| 1111 | acpi_device_wakeup(adev, ACPI_STATE_S0, false); |
| 1112 | } |
| 1113 | |
| 1114 | dev->pm_domain->detach = acpi_dev_pm_detach; |
| 1115 | return 0; |
| 1116 | } |
| 1117 | EXPORT_SYMBOL_GPL(acpi_dev_pm_attach); |
| 1118 | #endif /* CONFIG_PM */ |