1 /* 2 * Copyright 2012 Advanced Micro Devices, Inc. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 20 * OTHER DEALINGS IN THE SOFTWARE. 21 * 22 */ 23 24 #include <linux/pci.h> 25 #include <linux/acpi.h> 26 #include <linux/slab.h> 27 #include <linux/power_supply.h> 28 #include <acpi/acpi_drivers.h> 29 #include <acpi/acpi_bus.h> 30 #include <acpi/video.h> 31 32 #include "drmP.h" 33 #include "drm.h" 34 #include "drm_sarea.h" 35 #include "drm_crtc_helper.h" 36 #include "radeon.h" 37 #include "radeon_acpi.h" 38 #include "atom.h" 39 40 #include <linux/vga_switcheroo.h> 41 42 #define ACPI_AC_CLASS "ac_adapter" 43 44 extern void radeon_pm_acpi_event_handler(struct radeon_device *rdev); 45 46 struct atif_verify_interface { 47 u16 size; /* structure size in bytes (includes size field) */ 48 u16 version; /* version */ 49 u32 notification_mask; /* supported notifications mask */ 50 u32 function_bits; /* supported functions bit vector */ 51 } __packed; 52 53 struct atif_system_params { 54 u16 size; /* structure size in bytes (includes size field) */ 55 u32 valid_mask; /* valid flags mask */ 56 u32 flags; /* flags */ 57 u8 command_code; /* notify command code */ 58 } __packed; 59 60 struct atif_sbios_requests { 61 u16 size; /* structure size in bytes (includes size field) */ 62 u32 pending; /* pending sbios requests */ 63 u8 panel_exp_mode; /* panel expansion mode */ 64 u8 thermal_gfx; /* thermal state: target gfx controller */ 65 u8 thermal_state; /* thermal state: state id (0: exit state, non-0: state) */ 66 u8 forced_power_gfx; /* forced power state: target gfx controller */ 67 u8 forced_power_state; /* forced power state: state id */ 68 u8 system_power_src; /* system power source */ 69 u8 backlight_level; /* panel backlight level (0-255) */ 70 } __packed; 71 72 #define ATIF_NOTIFY_MASK 0x3 73 #define ATIF_NOTIFY_NONE 0 74 #define ATIF_NOTIFY_81 1 75 #define ATIF_NOTIFY_N 2 76 77 struct atcs_verify_interface { 78 u16 size; /* structure size in bytes (includes size field) */ 79 u16 version; /* version */ 80 u32 function_bits; /* supported functions bit vector */ 81 } __packed; 82 83 /* Call the ATIF method 84 */ 85 /** 86 * radeon_atif_call - call an ATIF method 87 * 88 * @handle: acpi handle 89 * @function: the ATIF function to execute 90 * @params: ATIF function params 91 * 92 * Executes the requested ATIF function (all asics). 93 * Returns a pointer to the acpi output buffer. 94 */ 95 static union acpi_object *radeon_atif_call(acpi_handle handle, int function, 96 struct acpi_buffer *params) 97 { 98 acpi_status status; 99 union acpi_object atif_arg_elements[2]; 100 struct acpi_object_list atif_arg; 101 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 102 103 atif_arg.count = 2; 104 atif_arg.pointer = &atif_arg_elements[0]; 105 106 atif_arg_elements[0].type = ACPI_TYPE_INTEGER; 107 atif_arg_elements[0].integer.value = function; 108 109 if (params) { 110 atif_arg_elements[1].type = ACPI_TYPE_BUFFER; 111 atif_arg_elements[1].buffer.length = params->length; 112 atif_arg_elements[1].buffer.pointer = params->pointer; 113 } else { 114 /* We need a second fake parameter */ 115 atif_arg_elements[1].type = ACPI_TYPE_INTEGER; 116 atif_arg_elements[1].integer.value = 0; 117 } 118 119 status = acpi_evaluate_object(handle, "ATIF", &atif_arg, &buffer); 120 121 /* Fail only if calling the method fails and ATIF is supported */ 122 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { 123 DRM_DEBUG_DRIVER("failed to evaluate ATIF got %s\n", 124 acpi_format_exception(status)); 125 kfree(buffer.pointer); 126 return NULL; 127 } 128 129 return buffer.pointer; 130 } 131 132 /** 133 * radeon_atif_parse_notification - parse supported notifications 134 * 135 * @n: supported notifications struct 136 * @mask: supported notifications mask from ATIF 137 * 138 * Use the supported notifications mask from ATIF function 139 * ATIF_FUNCTION_VERIFY_INTERFACE to determine what notifications 140 * are supported (all asics). 141 */ 142 static void radeon_atif_parse_notification(struct radeon_atif_notifications *n, u32 mask) 143 { 144 n->display_switch = mask & ATIF_DISPLAY_SWITCH_REQUEST_SUPPORTED; 145 n->expansion_mode_change = mask & ATIF_EXPANSION_MODE_CHANGE_REQUEST_SUPPORTED; 146 n->thermal_state = mask & ATIF_THERMAL_STATE_CHANGE_REQUEST_SUPPORTED; 147 n->forced_power_state = mask & ATIF_FORCED_POWER_STATE_CHANGE_REQUEST_SUPPORTED; 148 n->system_power_state = mask & ATIF_SYSTEM_POWER_SOURCE_CHANGE_REQUEST_SUPPORTED; 149 n->display_conf_change = mask & ATIF_DISPLAY_CONF_CHANGE_REQUEST_SUPPORTED; 150 n->px_gfx_switch = mask & ATIF_PX_GFX_SWITCH_REQUEST_SUPPORTED; 151 n->brightness_change = mask & ATIF_PANEL_BRIGHTNESS_CHANGE_REQUEST_SUPPORTED; 152 n->dgpu_display_event = mask & ATIF_DGPU_DISPLAY_EVENT_SUPPORTED; 153 } 154 155 /** 156 * radeon_atif_parse_functions - parse supported functions 157 * 158 * @f: supported functions struct 159 * @mask: supported functions mask from ATIF 160 * 161 * Use the supported functions mask from ATIF function 162 * ATIF_FUNCTION_VERIFY_INTERFACE to determine what functions 163 * are supported (all asics). 164 */ 165 static void radeon_atif_parse_functions(struct radeon_atif_functions *f, u32 mask) 166 { 167 f->system_params = mask & ATIF_GET_SYSTEM_PARAMETERS_SUPPORTED; 168 f->sbios_requests = mask & ATIF_GET_SYSTEM_BIOS_REQUESTS_SUPPORTED; 169 f->select_active_disp = mask & ATIF_SELECT_ACTIVE_DISPLAYS_SUPPORTED; 170 f->lid_state = mask & ATIF_GET_LID_STATE_SUPPORTED; 171 f->get_tv_standard = mask & ATIF_GET_TV_STANDARD_FROM_CMOS_SUPPORTED; 172 f->set_tv_standard = mask & ATIF_SET_TV_STANDARD_IN_CMOS_SUPPORTED; 173 f->get_panel_expansion_mode = mask & ATIF_GET_PANEL_EXPANSION_MODE_FROM_CMOS_SUPPORTED; 174 f->set_panel_expansion_mode = mask & ATIF_SET_PANEL_EXPANSION_MODE_IN_CMOS_SUPPORTED; 175 f->temperature_change = mask & ATIF_TEMPERATURE_CHANGE_NOTIFICATION_SUPPORTED; 176 f->graphics_device_types = mask & ATIF_GET_GRAPHICS_DEVICE_TYPES_SUPPORTED; 177 } 178 179 /** 180 * radeon_atif_verify_interface - verify ATIF 181 * 182 * @handle: acpi handle 183 * @atif: radeon atif struct 184 * 185 * Execute the ATIF_FUNCTION_VERIFY_INTERFACE ATIF function 186 * to initialize ATIF and determine what features are supported 187 * (all asics). 188 * returns 0 on success, error on failure. 189 */ 190 static int radeon_atif_verify_interface(acpi_handle handle, 191 struct radeon_atif *atif) 192 { 193 union acpi_object *info; 194 struct atif_verify_interface output; 195 size_t size; 196 int err = 0; 197 198 info = radeon_atif_call(handle, ATIF_FUNCTION_VERIFY_INTERFACE, NULL); 199 if (!info) 200 return -EIO; 201 202 memset(&output, 0, sizeof(output)); 203 204 size = *(u16 *) info->buffer.pointer; 205 if (size < 12) { 206 DRM_INFO("ATIF buffer is too small: %lu\n", size); 207 err = -EINVAL; 208 goto out; 209 } 210 size = min(sizeof(output), size); 211 212 memcpy(&output, info->buffer.pointer, size); 213 214 /* TODO: check version? */ 215 DRM_DEBUG_DRIVER("ATIF version %u\n", output.version); 216 217 radeon_atif_parse_notification(&atif->notifications, output.notification_mask); 218 radeon_atif_parse_functions(&atif->functions, output.function_bits); 219 220 out: 221 kfree(info); 222 return err; 223 } 224 225 /** 226 * radeon_atif_get_notification_params - determine notify configuration 227 * 228 * @handle: acpi handle 229 * @n: atif notification configuration struct 230 * 231 * Execute the ATIF_FUNCTION_GET_SYSTEM_PARAMETERS ATIF function 232 * to determine if a notifier is used and if so which one 233 * (all asics). This is either Notify(VGA, 0x81) or Notify(VGA, n) 234 * where n is specified in the result if a notifier is used. 235 * Returns 0 on success, error on failure. 236 */ 237 static int radeon_atif_get_notification_params(acpi_handle handle, 238 struct radeon_atif_notification_cfg *n) 239 { 240 union acpi_object *info; 241 struct atif_system_params params; 242 size_t size; 243 int err = 0; 244 245 info = radeon_atif_call(handle, ATIF_FUNCTION_GET_SYSTEM_PARAMETERS, NULL); 246 if (!info) { 247 err = -EIO; 248 goto out; 249 } 250 251 size = *(u16 *) info->buffer.pointer; 252 if (size < 10) { 253 err = -EINVAL; 254 goto out; 255 } 256 257 memset(¶ms, 0, sizeof(params)); 258 size = min(sizeof(params), size); 259 memcpy(¶ms, info->buffer.pointer, size); 260 261 DRM_DEBUG_DRIVER("SYSTEM_PARAMS: mask = %#x, flags = %#x\n", 262 params.flags, params.valid_mask); 263 params.flags = params.flags & params.valid_mask; 264 265 if ((params.flags & ATIF_NOTIFY_MASK) == ATIF_NOTIFY_NONE) { 266 n->enabled = false; 267 n->command_code = 0; 268 } else if ((params.flags & ATIF_NOTIFY_MASK) == ATIF_NOTIFY_81) { 269 n->enabled = true; 270 n->command_code = 0x81; 271 } else { 272 if (size < 11) { 273 err = -EINVAL; 274 goto out; 275 } 276 n->enabled = true; 277 n->command_code = params.command_code; 278 } 279 280 out: 281 DRM_DEBUG_DRIVER("Notification %s, command code = %#x\n", 282 (n->enabled ? "enabled" : "disabled"), 283 n->command_code); 284 kfree(info); 285 return err; 286 } 287 288 /** 289 * radeon_atif_get_sbios_requests - get requested sbios event 290 * 291 * @handle: acpi handle 292 * @req: atif sbios request struct 293 * 294 * Execute the ATIF_FUNCTION_GET_SYSTEM_BIOS_REQUESTS ATIF function 295 * to determine what requests the sbios is making to the driver 296 * (all asics). 297 * Returns 0 on success, error on failure. 298 */ 299 static int radeon_atif_get_sbios_requests(acpi_handle handle, 300 struct atif_sbios_requests *req) 301 { 302 union acpi_object *info; 303 size_t size; 304 int count = 0; 305 306 info = radeon_atif_call(handle, ATIF_FUNCTION_GET_SYSTEM_BIOS_REQUESTS, NULL); 307 if (!info) 308 return -EIO; 309 310 size = *(u16 *)info->buffer.pointer; 311 if (size < 0xd) { 312 count = -EINVAL; 313 goto out; 314 } 315 memset(req, 0, sizeof(*req)); 316 317 size = min(sizeof(*req), size); 318 memcpy(req, info->buffer.pointer, size); 319 DRM_DEBUG_DRIVER("SBIOS pending requests: %#x\n", req->pending); 320 321 count = hweight32(req->pending); 322 323 out: 324 kfree(info); 325 return count; 326 } 327 328 /** 329 * radeon_atif_handler - handle ATIF notify requests 330 * 331 * @rdev: radeon_device pointer 332 * @event: atif sbios request struct 333 * 334 * Checks the acpi event and if it matches an atif event, 335 * handles it. 336 * Returns NOTIFY code 337 */ 338 int radeon_atif_handler(struct radeon_device *rdev, 339 struct acpi_bus_event *event) 340 { 341 struct radeon_atif *atif = &rdev->atif; 342 struct atif_sbios_requests req; 343 acpi_handle handle; 344 int count; 345 346 DRM_DEBUG_DRIVER("event, device_class = %s, type = %#x\n", 347 event->device_class, event->type); 348 349 if (strcmp(event->device_class, ACPI_VIDEO_CLASS) != 0) 350 return NOTIFY_DONE; 351 352 if (!atif->notification_cfg.enabled || 353 event->type != atif->notification_cfg.command_code) 354 /* Not our event */ 355 return NOTIFY_DONE; 356 357 /* Check pending SBIOS requests */ 358 handle = DEVICE_ACPI_HANDLE(&rdev->pdev->dev); 359 count = radeon_atif_get_sbios_requests(handle, &req); 360 361 if (count <= 0) 362 return NOTIFY_DONE; 363 364 DRM_DEBUG_DRIVER("ATIF: %d pending SBIOS requests\n", count); 365 366 if (req.pending & ATIF_PANEL_BRIGHTNESS_CHANGE_REQUEST) { 367 struct radeon_encoder *enc = atif->encoder_for_bl; 368 369 if (enc) { 370 DRM_DEBUG_DRIVER("Changing brightness to %d\n", 371 req.backlight_level); 372 373 radeon_set_backlight_level(rdev, enc, req.backlight_level); 374 375 if (rdev->is_atom_bios) { 376 struct radeon_encoder_atom_dig *dig = enc->enc_priv; 377 backlight_force_update(dig->bl_dev, 378 BACKLIGHT_UPDATE_HOTKEY); 379 } else { 380 struct radeon_encoder_lvds *dig = enc->enc_priv; 381 backlight_force_update(dig->bl_dev, 382 BACKLIGHT_UPDATE_HOTKEY); 383 } 384 } 385 } 386 /* TODO: check other events */ 387 388 /* We've handled the event, stop the notifier chain. The ACPI interface 389 * overloads ACPI_VIDEO_NOTIFY_PROBE, we don't want to send that to 390 * userspace if the event was generated only to signal a SBIOS 391 * request. 392 */ 393 return NOTIFY_BAD; 394 } 395 396 /* Call the ATCS method 397 */ 398 /** 399 * radeon_atcs_call - call an ATCS method 400 * 401 * @handle: acpi handle 402 * @function: the ATCS function to execute 403 * @params: ATCS function params 404 * 405 * Executes the requested ATCS function (all asics). 406 * Returns a pointer to the acpi output buffer. 407 */ 408 static union acpi_object *radeon_atcs_call(acpi_handle handle, int function, 409 struct acpi_buffer *params) 410 { 411 acpi_status status; 412 union acpi_object atcs_arg_elements[2]; 413 struct acpi_object_list atcs_arg; 414 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 415 416 atcs_arg.count = 2; 417 atcs_arg.pointer = &atcs_arg_elements[0]; 418 419 atcs_arg_elements[0].type = ACPI_TYPE_INTEGER; 420 atcs_arg_elements[0].integer.value = function; 421 422 if (params) { 423 atcs_arg_elements[1].type = ACPI_TYPE_BUFFER; 424 atcs_arg_elements[1].buffer.length = params->length; 425 atcs_arg_elements[1].buffer.pointer = params->pointer; 426 } else { 427 /* We need a second fake parameter */ 428 atcs_arg_elements[1].type = ACPI_TYPE_INTEGER; 429 atcs_arg_elements[1].integer.value = 0; 430 } 431 432 status = acpi_evaluate_object(handle, "ATCS", &atcs_arg, &buffer); 433 434 /* Fail only if calling the method fails and ATIF is supported */ 435 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { 436 DRM_DEBUG_DRIVER("failed to evaluate ATCS got %s\n", 437 acpi_format_exception(status)); 438 kfree(buffer.pointer); 439 return NULL; 440 } 441 442 return buffer.pointer; 443 } 444 445 /** 446 * radeon_atcs_parse_functions - parse supported functions 447 * 448 * @f: supported functions struct 449 * @mask: supported functions mask from ATCS 450 * 451 * Use the supported functions mask from ATCS function 452 * ATCS_FUNCTION_VERIFY_INTERFACE to determine what functions 453 * are supported (all asics). 454 */ 455 static void radeon_atcs_parse_functions(struct radeon_atcs_functions *f, u32 mask) 456 { 457 f->get_ext_state = mask & ATCS_GET_EXTERNAL_STATE_SUPPORTED; 458 f->pcie_perf_req = mask & ATCS_PCIE_PERFORMANCE_REQUEST_SUPPORTED; 459 f->pcie_dev_rdy = mask & ATCS_PCIE_DEVICE_READY_NOTIFICATION_SUPPORTED; 460 f->pcie_bus_width = mask & ATCS_SET_PCIE_BUS_WIDTH_SUPPORTED; 461 } 462 463 /** 464 * radeon_atcs_verify_interface - verify ATCS 465 * 466 * @handle: acpi handle 467 * @atcs: radeon atcs struct 468 * 469 * Execute the ATCS_FUNCTION_VERIFY_INTERFACE ATCS function 470 * to initialize ATCS and determine what features are supported 471 * (all asics). 472 * returns 0 on success, error on failure. 473 */ 474 static int radeon_atcs_verify_interface(acpi_handle handle, 475 struct radeon_atcs *atcs) 476 { 477 union acpi_object *info; 478 struct atcs_verify_interface output; 479 size_t size; 480 int err = 0; 481 482 info = radeon_atcs_call(handle, ATCS_FUNCTION_VERIFY_INTERFACE, NULL); 483 if (!info) 484 return -EIO; 485 486 memset(&output, 0, sizeof(output)); 487 488 size = *(u16 *) info->buffer.pointer; 489 if (size < 8) { 490 DRM_INFO("ATCS buffer is too small: %lu\n", size); 491 err = -EINVAL; 492 goto out; 493 } 494 size = min(sizeof(output), size); 495 496 memcpy(&output, info->buffer.pointer, size); 497 498 /* TODO: check version? */ 499 DRM_DEBUG_DRIVER("ATCS version %u\n", output.version); 500 501 radeon_atcs_parse_functions(&atcs->functions, output.function_bits); 502 503 out: 504 kfree(info); 505 return err; 506 } 507 508 /** 509 * radeon_acpi_event - handle notify events 510 * 511 * @nb: notifier block 512 * @val: val 513 * @data: acpi event 514 * 515 * Calls relevant radeon functions in response to various 516 * acpi events. 517 * Returns NOTIFY code 518 */ 519 static int radeon_acpi_event(struct notifier_block *nb, 520 unsigned long val, 521 void *data) 522 { 523 struct radeon_device *rdev = container_of(nb, struct radeon_device, acpi_nb); 524 struct acpi_bus_event *entry = (struct acpi_bus_event *)data; 525 526 if (strcmp(entry->device_class, ACPI_AC_CLASS) == 0) { 527 if (power_supply_is_system_supplied() > 0) 528 DRM_DEBUG_DRIVER("pm: AC\n"); 529 else 530 DRM_DEBUG_DRIVER("pm: DC\n"); 531 532 radeon_pm_acpi_event_handler(rdev); 533 } 534 535 /* Check for pending SBIOS requests */ 536 return radeon_atif_handler(rdev, entry); 537 } 538 539 /* Call all ACPI methods here */ 540 /** 541 * radeon_acpi_init - init driver acpi support 542 * 543 * @rdev: radeon_device pointer 544 * 545 * Verifies the AMD ACPI interfaces and registers with the acpi 546 * notifier chain (all asics). 547 * Returns 0 on success, error on failure. 548 */ 549 int radeon_acpi_init(struct radeon_device *rdev) 550 { 551 acpi_handle handle; 552 struct radeon_atif *atif = &rdev->atif; 553 struct radeon_atcs *atcs = &rdev->atcs; 554 int ret; 555 556 /* Get the device handle */ 557 handle = DEVICE_ACPI_HANDLE(&rdev->pdev->dev); 558 559 /* No need to proceed if we're sure that ATIF is not supported */ 560 if (!ASIC_IS_AVIVO(rdev) || !rdev->bios || !handle) 561 return 0; 562 563 /* Call the ATCS method */ 564 ret = radeon_atcs_verify_interface(handle, atcs); 565 if (ret) { 566 DRM_DEBUG_DRIVER("Call to ATCS verify_interface failed: %d\n", ret); 567 } 568 569 /* Call the ATIF method */ 570 ret = radeon_atif_verify_interface(handle, atif); 571 if (ret) { 572 DRM_DEBUG_DRIVER("Call to ATIF verify_interface failed: %d\n", ret); 573 goto out; 574 } 575 576 if (atif->notifications.brightness_change) { 577 struct drm_encoder *tmp; 578 struct radeon_encoder *target = NULL; 579 580 /* Find the encoder controlling the brightness */ 581 list_for_each_entry(tmp, &rdev->ddev->mode_config.encoder_list, 582 head) { 583 struct radeon_encoder *enc = to_radeon_encoder(tmp); 584 585 if ((enc->devices & (ATOM_DEVICE_LCD_SUPPORT)) && 586 enc->enc_priv) { 587 if (rdev->is_atom_bios) { 588 struct radeon_encoder_atom_dig *dig = enc->enc_priv; 589 if (dig->bl_dev) { 590 target = enc; 591 break; 592 } 593 } else { 594 struct radeon_encoder_lvds *dig = enc->enc_priv; 595 if (dig->bl_dev) { 596 target = enc; 597 break; 598 } 599 } 600 } 601 } 602 603 atif->encoder_for_bl = target; 604 if (!target) { 605 /* Brightness change notification is enabled, but we 606 * didn't find a backlight controller, this should 607 * never happen. 608 */ 609 DRM_ERROR("Cannot find a backlight controller\n"); 610 } 611 } 612 613 if (atif->functions.sbios_requests && !atif->functions.system_params) { 614 /* XXX check this workraround, if sbios request function is 615 * present we have to see how it's configured in the system 616 * params 617 */ 618 atif->functions.system_params = true; 619 } 620 621 if (atif->functions.system_params) { 622 ret = radeon_atif_get_notification_params(handle, 623 &atif->notification_cfg); 624 if (ret) { 625 DRM_DEBUG_DRIVER("Call to GET_SYSTEM_PARAMS failed: %d\n", 626 ret); 627 /* Disable notification */ 628 atif->notification_cfg.enabled = false; 629 } 630 } 631 632 out: 633 rdev->acpi_nb.notifier_call = radeon_acpi_event; 634 register_acpi_notifier(&rdev->acpi_nb); 635 636 return ret; 637 } 638 639 /** 640 * radeon_acpi_fini - tear down driver acpi support 641 * 642 * @rdev: radeon_device pointer 643 * 644 * Unregisters with the acpi notifier chain (all asics). 645 */ 646 void radeon_acpi_fini(struct radeon_device *rdev) 647 { 648 unregister_acpi_notifier(&rdev->acpi_nb); 649 } 650