1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * button.c - ACPI Button Driver 4 * 5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 7 */ 8 9 #define pr_fmt(fmt) "ACPI: button: " fmt 10 11 #include <linux/compiler.h> 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/types.h> 16 #include <linux/proc_fs.h> 17 #include <linux/seq_file.h> 18 #include <linux/input.h> 19 #include <linux/slab.h> 20 #include <linux/acpi.h> 21 #include <linux/dmi.h> 22 #include <acpi/button.h> 23 24 #define ACPI_BUTTON_CLASS "button" 25 #define ACPI_BUTTON_FILE_STATE "state" 26 #define ACPI_BUTTON_TYPE_UNKNOWN 0x00 27 #define ACPI_BUTTON_NOTIFY_STATUS 0x80 28 29 #define ACPI_BUTTON_SUBCLASS_POWER "power" 30 #define ACPI_BUTTON_DEVICE_NAME_POWER "Power Button" 31 #define ACPI_BUTTON_TYPE_POWER 0x01 32 33 #define ACPI_BUTTON_SUBCLASS_SLEEP "sleep" 34 #define ACPI_BUTTON_DEVICE_NAME_SLEEP "Sleep Button" 35 #define ACPI_BUTTON_TYPE_SLEEP 0x03 36 37 #define ACPI_BUTTON_SUBCLASS_LID "lid" 38 #define ACPI_BUTTON_DEVICE_NAME_LID "Lid Switch" 39 #define ACPI_BUTTON_TYPE_LID 0x05 40 41 enum { 42 ACPI_BUTTON_LID_INIT_IGNORE, 43 ACPI_BUTTON_LID_INIT_OPEN, 44 ACPI_BUTTON_LID_INIT_METHOD, 45 ACPI_BUTTON_LID_INIT_DISABLED, 46 }; 47 48 static const char * const lid_init_state_str[] = { 49 [ACPI_BUTTON_LID_INIT_IGNORE] = "ignore", 50 [ACPI_BUTTON_LID_INIT_OPEN] = "open", 51 [ACPI_BUTTON_LID_INIT_METHOD] = "method", 52 [ACPI_BUTTON_LID_INIT_DISABLED] = "disabled", 53 }; 54 55 MODULE_AUTHOR("Paul Diefenbaugh"); 56 MODULE_DESCRIPTION("ACPI Button Driver"); 57 MODULE_LICENSE("GPL"); 58 59 static const struct acpi_device_id button_device_ids[] = { 60 {ACPI_BUTTON_HID_LID, 0}, 61 {ACPI_BUTTON_HID_SLEEP, 0}, 62 {ACPI_BUTTON_HID_SLEEPF, 0}, 63 {ACPI_BUTTON_HID_POWER, 0}, 64 {ACPI_BUTTON_HID_POWERF, 0}, 65 {"", 0}, 66 }; 67 MODULE_DEVICE_TABLE(acpi, button_device_ids); 68 69 /* Please keep this list sorted alphabetically by vendor and model */ 70 static const struct dmi_system_id dmi_lid_quirks[] = { 71 { 72 /* GP-electronic T701, _LID method points to a floating GPIO */ 73 .matches = { 74 DMI_MATCH(DMI_SYS_VENDOR, "Insyde"), 75 DMI_MATCH(DMI_PRODUCT_NAME, "T701"), 76 DMI_MATCH(DMI_BIOS_VERSION, "BYT70A.YNCHENG.WIN.007"), 77 }, 78 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED, 79 }, 80 { 81 /* Nextbook Ares 8A tablet, _LID device always reports lid closed */ 82 .matches = { 83 DMI_MATCH(DMI_SYS_VENDOR, "Insyde"), 84 DMI_MATCH(DMI_PRODUCT_NAME, "CherryTrail"), 85 DMI_MATCH(DMI_BIOS_VERSION, "M882"), 86 }, 87 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED, 88 }, 89 { 90 /* 91 * Lenovo Yoga 9 14ITL5, initial notification of the LID device 92 * never happens. 93 */ 94 .matches = { 95 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 96 DMI_MATCH(DMI_PRODUCT_NAME, "82BG"), 97 }, 98 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN, 99 }, 100 { 101 /* 102 * Medion Akoya E2215T, notification of the LID device only 103 * happens on close, not on open and _LID always returns closed. 104 */ 105 .matches = { 106 DMI_MATCH(DMI_SYS_VENDOR, "MEDION"), 107 DMI_MATCH(DMI_PRODUCT_NAME, "E2215T"), 108 }, 109 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN, 110 }, 111 { 112 /* 113 * Medion Akoya E2228T, notification of the LID device only 114 * happens on close, not on open and _LID always returns closed. 115 */ 116 .matches = { 117 DMI_MATCH(DMI_SYS_VENDOR, "MEDION"), 118 DMI_MATCH(DMI_PRODUCT_NAME, "E2228T"), 119 }, 120 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN, 121 }, 122 { 123 /* 124 * Razer Blade Stealth 13 late 2019, notification of the LID device 125 * only happens on close, not on open and _LID always returns closed. 126 */ 127 .matches = { 128 DMI_MATCH(DMI_SYS_VENDOR, "Razer"), 129 DMI_MATCH(DMI_PRODUCT_NAME, "Razer Blade Stealth 13 Late 2019"), 130 }, 131 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN, 132 }, 133 {} 134 }; 135 136 static int acpi_button_add(struct acpi_device *device); 137 static void acpi_button_remove(struct acpi_device *device); 138 139 #ifdef CONFIG_PM_SLEEP 140 static int acpi_button_suspend(struct device *dev); 141 static int acpi_button_resume(struct device *dev); 142 #else 143 #define acpi_button_suspend NULL 144 #define acpi_button_resume NULL 145 #endif 146 static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume); 147 148 static struct acpi_driver acpi_button_driver = { 149 .name = "button", 150 .class = ACPI_BUTTON_CLASS, 151 .ids = button_device_ids, 152 .ops = { 153 .add = acpi_button_add, 154 .remove = acpi_button_remove, 155 }, 156 .drv.pm = &acpi_button_pm, 157 }; 158 159 struct acpi_button { 160 unsigned int type; 161 struct input_dev *input; 162 char phys[32]; /* for input device */ 163 unsigned long pushed; 164 int last_state; 165 ktime_t last_time; 166 bool suspended; 167 bool lid_state_initialized; 168 }; 169 170 static struct acpi_device *lid_device; 171 static long lid_init_state = -1; 172 173 static unsigned long lid_report_interval __read_mostly = 500; 174 module_param(lid_report_interval, ulong, 0644); 175 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events"); 176 177 /* FS Interface (/proc) */ 178 static struct proc_dir_entry *acpi_button_dir; 179 static struct proc_dir_entry *acpi_lid_dir; 180 181 static int acpi_lid_evaluate_state(struct acpi_device *device) 182 { 183 unsigned long long lid_state; 184 acpi_status status; 185 186 status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state); 187 if (ACPI_FAILURE(status)) 188 return -ENODEV; 189 190 return lid_state ? 1 : 0; 191 } 192 193 static int acpi_lid_notify_state(struct acpi_device *device, int state) 194 { 195 struct acpi_button *button = acpi_driver_data(device); 196 ktime_t next_report; 197 bool do_update; 198 199 /* 200 * In lid_init_state=ignore mode, if user opens/closes lid 201 * frequently with "open" missing, and "last_time" is also updated 202 * frequently, "close" cannot be delivered to the userspace. 203 * So "last_time" is only updated after a timeout or an actual 204 * switch. 205 */ 206 if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE || 207 button->last_state != !!state) 208 do_update = true; 209 else 210 do_update = false; 211 212 next_report = ktime_add(button->last_time, 213 ms_to_ktime(lid_report_interval)); 214 if (button->last_state == !!state && 215 ktime_after(ktime_get(), next_report)) { 216 /* Complain the buggy firmware */ 217 pr_warn_once("The lid device is not compliant to SW_LID.\n"); 218 219 /* 220 * Send the unreliable complement switch event: 221 * 222 * On most platforms, the lid device is reliable. However 223 * there are exceptions: 224 * 1. Platforms returning initial lid state as "close" by 225 * default after booting/resuming: 226 * https://bugzilla.kernel.org/show_bug.cgi?id=89211 227 * https://bugzilla.kernel.org/show_bug.cgi?id=106151 228 * 2. Platforms never reporting "open" events: 229 * https://bugzilla.kernel.org/show_bug.cgi?id=106941 230 * On these buggy platforms, the usage model of the ACPI 231 * lid device actually is: 232 * 1. The initial returning value of _LID may not be 233 * reliable. 234 * 2. The open event may not be reliable. 235 * 3. The close event is reliable. 236 * 237 * But SW_LID is typed as input switch event, the input 238 * layer checks if the event is redundant. Hence if the 239 * state is not switched, the userspace cannot see this 240 * platform triggered reliable event. By inserting a 241 * complement switch event, it then is guaranteed that the 242 * platform triggered reliable one can always be seen by 243 * the userspace. 244 */ 245 if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) { 246 do_update = true; 247 /* 248 * Do generate complement switch event for "close" 249 * as "close" is reliable and wrong "open" won't 250 * trigger unexpected behaviors. 251 * Do not generate complement switch event for 252 * "open" as "open" is not reliable and wrong 253 * "close" will trigger unexpected behaviors. 254 */ 255 if (!state) { 256 input_report_switch(button->input, 257 SW_LID, state); 258 input_sync(button->input); 259 } 260 } 261 } 262 /* Send the platform triggered reliable event */ 263 if (do_update) { 264 acpi_handle_debug(device->handle, "ACPI LID %s\n", 265 state ? "open" : "closed"); 266 input_report_switch(button->input, SW_LID, !state); 267 input_sync(button->input); 268 button->last_state = !!state; 269 button->last_time = ktime_get(); 270 } 271 272 return 0; 273 } 274 275 static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq, 276 void *offset) 277 { 278 struct acpi_device *device = seq->private; 279 int state; 280 281 state = acpi_lid_evaluate_state(device); 282 seq_printf(seq, "state: %s\n", 283 state < 0 ? "unsupported" : (state ? "open" : "closed")); 284 return 0; 285 } 286 287 static int acpi_button_add_fs(struct acpi_device *device) 288 { 289 struct acpi_button *button = acpi_driver_data(device); 290 struct proc_dir_entry *entry = NULL; 291 int ret = 0; 292 293 /* procfs I/F for ACPI lid device only */ 294 if (button->type != ACPI_BUTTON_TYPE_LID) 295 return 0; 296 297 if (acpi_button_dir || acpi_lid_dir) { 298 pr_info("More than one Lid device found!\n"); 299 return -EEXIST; 300 } 301 302 /* create /proc/acpi/button */ 303 acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir); 304 if (!acpi_button_dir) 305 return -ENODEV; 306 307 /* create /proc/acpi/button/lid */ 308 acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir); 309 if (!acpi_lid_dir) { 310 ret = -ENODEV; 311 goto remove_button_dir; 312 } 313 314 /* create /proc/acpi/button/lid/LID/ */ 315 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir); 316 if (!acpi_device_dir(device)) { 317 ret = -ENODEV; 318 goto remove_lid_dir; 319 } 320 321 /* create /proc/acpi/button/lid/LID/state */ 322 entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO, 323 acpi_device_dir(device), acpi_button_state_seq_show, 324 device); 325 if (!entry) { 326 ret = -ENODEV; 327 goto remove_dev_dir; 328 } 329 330 done: 331 return ret; 332 333 remove_dev_dir: 334 remove_proc_entry(acpi_device_bid(device), 335 acpi_lid_dir); 336 acpi_device_dir(device) = NULL; 337 remove_lid_dir: 338 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir); 339 acpi_lid_dir = NULL; 340 remove_button_dir: 341 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir); 342 acpi_button_dir = NULL; 343 goto done; 344 } 345 346 static int acpi_button_remove_fs(struct acpi_device *device) 347 { 348 struct acpi_button *button = acpi_driver_data(device); 349 350 if (button->type != ACPI_BUTTON_TYPE_LID) 351 return 0; 352 353 remove_proc_entry(ACPI_BUTTON_FILE_STATE, 354 acpi_device_dir(device)); 355 remove_proc_entry(acpi_device_bid(device), 356 acpi_lid_dir); 357 acpi_device_dir(device) = NULL; 358 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir); 359 acpi_lid_dir = NULL; 360 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir); 361 acpi_button_dir = NULL; 362 363 return 0; 364 } 365 366 /* Driver Interface */ 367 int acpi_lid_open(void) 368 { 369 if (!lid_device) 370 return -ENODEV; 371 372 return acpi_lid_evaluate_state(lid_device); 373 } 374 EXPORT_SYMBOL(acpi_lid_open); 375 376 static int acpi_lid_update_state(struct acpi_device *device, 377 bool signal_wakeup) 378 { 379 int state; 380 381 state = acpi_lid_evaluate_state(device); 382 if (state < 0) 383 return state; 384 385 if (state && signal_wakeup) 386 acpi_pm_wakeup_event(&device->dev); 387 388 return acpi_lid_notify_state(device, state); 389 } 390 391 static void acpi_lid_initialize_state(struct acpi_device *device) 392 { 393 struct acpi_button *button = acpi_driver_data(device); 394 395 switch (lid_init_state) { 396 case ACPI_BUTTON_LID_INIT_OPEN: 397 (void)acpi_lid_notify_state(device, 1); 398 break; 399 case ACPI_BUTTON_LID_INIT_METHOD: 400 (void)acpi_lid_update_state(device, false); 401 break; 402 case ACPI_BUTTON_LID_INIT_IGNORE: 403 default: 404 break; 405 } 406 407 button->lid_state_initialized = true; 408 } 409 410 static void acpi_lid_notify(acpi_handle handle, u32 event, void *data) 411 { 412 struct acpi_device *device = data; 413 struct acpi_button *button; 414 415 if (event != ACPI_BUTTON_NOTIFY_STATUS) { 416 acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n", 417 event); 418 return; 419 } 420 421 button = acpi_driver_data(device); 422 if (!button->lid_state_initialized) 423 return; 424 425 acpi_lid_update_state(device, true); 426 } 427 428 static void acpi_button_notify(acpi_handle handle, u32 event, void *data) 429 { 430 struct acpi_device *device = data; 431 struct acpi_button *button; 432 struct input_dev *input; 433 int keycode; 434 435 if (event != ACPI_BUTTON_NOTIFY_STATUS) { 436 acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n", 437 event); 438 return; 439 } 440 441 acpi_pm_wakeup_event(&device->dev); 442 443 button = acpi_driver_data(device); 444 if (button->suspended) 445 return; 446 447 input = button->input; 448 keycode = test_bit(KEY_SLEEP, input->keybit) ? KEY_SLEEP : KEY_POWER; 449 450 input_report_key(input, keycode, 1); 451 input_sync(input); 452 input_report_key(input, keycode, 0); 453 input_sync(input); 454 455 acpi_bus_generate_netlink_event(device->pnp.device_class, 456 dev_name(&device->dev), 457 event, ++button->pushed); 458 } 459 460 static void acpi_button_notify_run(void *data) 461 { 462 acpi_button_notify(NULL, ACPI_BUTTON_NOTIFY_STATUS, data); 463 } 464 465 static u32 acpi_button_event(void *data) 466 { 467 acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_button_notify_run, data); 468 return ACPI_INTERRUPT_HANDLED; 469 } 470 471 #ifdef CONFIG_PM_SLEEP 472 static int acpi_button_suspend(struct device *dev) 473 { 474 struct acpi_device *device = to_acpi_device(dev); 475 struct acpi_button *button = acpi_driver_data(device); 476 477 button->suspended = true; 478 return 0; 479 } 480 481 static int acpi_button_resume(struct device *dev) 482 { 483 struct acpi_device *device = to_acpi_device(dev); 484 struct acpi_button *button = acpi_driver_data(device); 485 486 button->suspended = false; 487 if (button->type == ACPI_BUTTON_TYPE_LID) { 488 button->last_state = !!acpi_lid_evaluate_state(device); 489 button->last_time = ktime_get(); 490 acpi_lid_initialize_state(device); 491 } 492 return 0; 493 } 494 #endif 495 496 static int acpi_lid_input_open(struct input_dev *input) 497 { 498 struct acpi_device *device = input_get_drvdata(input); 499 struct acpi_button *button = acpi_driver_data(device); 500 501 button->last_state = !!acpi_lid_evaluate_state(device); 502 button->last_time = ktime_get(); 503 acpi_lid_initialize_state(device); 504 505 return 0; 506 } 507 508 static int acpi_button_add(struct acpi_device *device) 509 { 510 acpi_notify_handler handler; 511 struct acpi_button *button; 512 struct input_dev *input; 513 const char *hid = acpi_device_hid(device); 514 acpi_status status; 515 char *name, *class; 516 int error = 0; 517 518 if (!strcmp(hid, ACPI_BUTTON_HID_LID) && 519 lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED) 520 return -ENODEV; 521 522 button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL); 523 if (!button) 524 return -ENOMEM; 525 526 device->driver_data = button; 527 528 button->input = input = input_allocate_device(); 529 if (!input) { 530 error = -ENOMEM; 531 goto err_free_button; 532 } 533 534 name = acpi_device_name(device); 535 class = acpi_device_class(device); 536 537 if (!strcmp(hid, ACPI_BUTTON_HID_POWER) || 538 !strcmp(hid, ACPI_BUTTON_HID_POWERF)) { 539 button->type = ACPI_BUTTON_TYPE_POWER; 540 handler = acpi_button_notify; 541 strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER); 542 sprintf(class, "%s/%s", 543 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER); 544 } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) || 545 !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) { 546 button->type = ACPI_BUTTON_TYPE_SLEEP; 547 handler = acpi_button_notify; 548 strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP); 549 sprintf(class, "%s/%s", 550 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP); 551 } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) { 552 button->type = ACPI_BUTTON_TYPE_LID; 553 handler = acpi_lid_notify; 554 strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID); 555 sprintf(class, "%s/%s", 556 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID); 557 input->open = acpi_lid_input_open; 558 } else { 559 pr_info("Unsupported hid [%s]\n", hid); 560 error = -ENODEV; 561 } 562 563 if (!error) 564 error = acpi_button_add_fs(device); 565 566 if (error) { 567 input_free_device(input); 568 goto err_free_button; 569 } 570 571 snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid); 572 573 input->name = name; 574 input->phys = button->phys; 575 input->id.bustype = BUS_HOST; 576 input->id.product = button->type; 577 input->dev.parent = &device->dev; 578 579 switch (button->type) { 580 case ACPI_BUTTON_TYPE_POWER: 581 input_set_capability(input, EV_KEY, KEY_POWER); 582 break; 583 584 case ACPI_BUTTON_TYPE_SLEEP: 585 input_set_capability(input, EV_KEY, KEY_SLEEP); 586 break; 587 588 case ACPI_BUTTON_TYPE_LID: 589 input_set_capability(input, EV_SW, SW_LID); 590 break; 591 } 592 593 input_set_drvdata(input, device); 594 error = input_register_device(input); 595 if (error) 596 goto err_remove_fs; 597 598 switch (device->device_type) { 599 case ACPI_BUS_TYPE_POWER_BUTTON: 600 status = acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON, 601 acpi_button_event, 602 device); 603 break; 604 case ACPI_BUS_TYPE_SLEEP_BUTTON: 605 status = acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON, 606 acpi_button_event, 607 device); 608 break; 609 default: 610 status = acpi_install_notify_handler(device->handle, 611 ACPI_DEVICE_NOTIFY, handler, 612 device); 613 break; 614 } 615 if (ACPI_FAILURE(status)) { 616 error = -ENODEV; 617 goto err_input_unregister; 618 } 619 620 if (button->type == ACPI_BUTTON_TYPE_LID) { 621 /* 622 * This assumes there's only one lid device, or if there are 623 * more we only care about the last one... 624 */ 625 lid_device = device; 626 } 627 628 device_init_wakeup(&device->dev, true); 629 pr_info("%s [%s]\n", name, acpi_device_bid(device)); 630 return 0; 631 632 err_input_unregister: 633 input_unregister_device(input); 634 err_remove_fs: 635 acpi_button_remove_fs(device); 636 err_free_button: 637 kfree(button); 638 return error; 639 } 640 641 static void acpi_button_remove(struct acpi_device *device) 642 { 643 struct acpi_button *button = acpi_driver_data(device); 644 645 switch (device->device_type) { 646 case ACPI_BUS_TYPE_POWER_BUTTON: 647 acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON, 648 acpi_button_event); 649 break; 650 case ACPI_BUS_TYPE_SLEEP_BUTTON: 651 acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON, 652 acpi_button_event); 653 break; 654 default: 655 acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, 656 button->type == ACPI_BUTTON_TYPE_LID ? 657 acpi_lid_notify : 658 acpi_button_notify); 659 break; 660 } 661 acpi_os_wait_events_complete(); 662 663 acpi_button_remove_fs(device); 664 input_unregister_device(button->input); 665 kfree(button); 666 } 667 668 static int param_set_lid_init_state(const char *val, 669 const struct kernel_param *kp) 670 { 671 int i; 672 673 i = sysfs_match_string(lid_init_state_str, val); 674 if (i < 0) 675 return i; 676 677 lid_init_state = i; 678 pr_info("Initial lid state set to '%s'\n", lid_init_state_str[i]); 679 return 0; 680 } 681 682 static int param_get_lid_init_state(char *buf, const struct kernel_param *kp) 683 { 684 int i, c = 0; 685 686 for (i = 0; i < ARRAY_SIZE(lid_init_state_str); i++) 687 if (i == lid_init_state) 688 c += sprintf(buf + c, "[%s] ", lid_init_state_str[i]); 689 else 690 c += sprintf(buf + c, "%s ", lid_init_state_str[i]); 691 692 buf[c - 1] = '\n'; /* Replace the final space with a newline */ 693 694 return c; 695 } 696 697 module_param_call(lid_init_state, 698 param_set_lid_init_state, param_get_lid_init_state, 699 NULL, 0644); 700 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state"); 701 702 static int acpi_button_register_driver(struct acpi_driver *driver) 703 { 704 const struct dmi_system_id *dmi_id; 705 706 if (lid_init_state == -1) { 707 dmi_id = dmi_first_match(dmi_lid_quirks); 708 if (dmi_id) 709 lid_init_state = (long)dmi_id->driver_data; 710 else 711 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD; 712 } 713 714 /* 715 * Modules such as nouveau.ko and i915.ko have a link time dependency 716 * on acpi_lid_open(), and would therefore not be loadable on ACPI 717 * capable kernels booted in non-ACPI mode if the return value of 718 * acpi_bus_register_driver() is returned from here with ACPI disabled 719 * when this driver is built as a module. 720 */ 721 if (acpi_disabled) 722 return 0; 723 724 return acpi_bus_register_driver(driver); 725 } 726 727 static void acpi_button_unregister_driver(struct acpi_driver *driver) 728 { 729 if (!acpi_disabled) 730 acpi_bus_unregister_driver(driver); 731 } 732 733 module_driver(acpi_button_driver, acpi_button_register_driver, 734 acpi_button_unregister_driver); 735