GNU Linux-libre 6.7.9-gnu
[releases.git] / 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 <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);