drivers/acpi/button.c

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