treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
[sfrench/cifs-2.6.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 PREFIX "ACPI: "
25
26 #define ACPI_BUTTON_CLASS               "button"
27 #define ACPI_BUTTON_FILE_INFO           "info"
28 #define ACPI_BUTTON_FILE_STATE          "state"
29 #define ACPI_BUTTON_TYPE_UNKNOWN        0x00
30 #define ACPI_BUTTON_NOTIFY_STATUS       0x80
31
32 #define ACPI_BUTTON_SUBCLASS_POWER      "power"
33 #define ACPI_BUTTON_HID_POWER           "PNP0C0C"
34 #define ACPI_BUTTON_DEVICE_NAME_POWER   "Power Button"
35 #define ACPI_BUTTON_TYPE_POWER          0x01
36
37 #define ACPI_BUTTON_SUBCLASS_SLEEP      "sleep"
38 #define ACPI_BUTTON_HID_SLEEP           "PNP0C0E"
39 #define ACPI_BUTTON_DEVICE_NAME_SLEEP   "Sleep Button"
40 #define ACPI_BUTTON_TYPE_SLEEP          0x03
41
42 #define ACPI_BUTTON_SUBCLASS_LID        "lid"
43 #define ACPI_BUTTON_HID_LID             "PNP0C0D"
44 #define ACPI_BUTTON_DEVICE_NAME_LID     "Lid Switch"
45 #define ACPI_BUTTON_TYPE_LID            0x05
46
47 #define ACPI_BUTTON_LID_INIT_IGNORE     0x00
48 #define ACPI_BUTTON_LID_INIT_OPEN       0x01
49 #define ACPI_BUTTON_LID_INIT_METHOD     0x02
50
51 #define _COMPONENT              ACPI_BUTTON_COMPONENT
52 ACPI_MODULE_NAME("button");
53
54 MODULE_AUTHOR("Paul Diefenbaugh");
55 MODULE_DESCRIPTION("ACPI Button Driver");
56 MODULE_LICENSE("GPL");
57
58 static const struct acpi_device_id button_device_ids[] = {
59         {ACPI_BUTTON_HID_LID,    0},
60         {ACPI_BUTTON_HID_SLEEP,  0},
61         {ACPI_BUTTON_HID_SLEEPF, 0},
62         {ACPI_BUTTON_HID_POWER,  0},
63         {ACPI_BUTTON_HID_POWERF, 0},
64         {"", 0},
65 };
66 MODULE_DEVICE_TABLE(acpi, button_device_ids);
67
68 /*
69  * Some devices which don't even have a lid in anyway have a broken _LID
70  * method (e.g. pointing to a floating gpio pin) causing spurious LID events.
71  */
72 static const struct dmi_system_id lid_blacklst[] = {
73         {
74                 /* GP-electronic T701 */
75                 .matches = {
76                         DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
77                         DMI_MATCH(DMI_PRODUCT_NAME, "T701"),
78                         DMI_MATCH(DMI_BIOS_VERSION, "BYT70A.YNCHENG.WIN.007"),
79                 },
80         },
81         {}
82 };
83
84 static int acpi_button_add(struct acpi_device *device);
85 static int acpi_button_remove(struct acpi_device *device);
86 static void acpi_button_notify(struct acpi_device *device, u32 event);
87
88 #ifdef CONFIG_PM_SLEEP
89 static int acpi_button_suspend(struct device *dev);
90 static int acpi_button_resume(struct device *dev);
91 #else
92 #define acpi_button_suspend NULL
93 #define acpi_button_resume NULL
94 #endif
95 static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
96
97 static struct acpi_driver acpi_button_driver = {
98         .name = "button",
99         .class = ACPI_BUTTON_CLASS,
100         .ids = button_device_ids,
101         .ops = {
102                 .add = acpi_button_add,
103                 .remove = acpi_button_remove,
104                 .notify = acpi_button_notify,
105         },
106         .drv.pm = &acpi_button_pm,
107 };
108
109 struct acpi_button {
110         unsigned int type;
111         struct input_dev *input;
112         char phys[32];                  /* for input device */
113         unsigned long pushed;
114         int last_state;
115         ktime_t last_time;
116         bool suspended;
117 };
118
119 static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
120 static struct acpi_device *lid_device;
121 static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
122
123 static unsigned long lid_report_interval __read_mostly = 500;
124 module_param(lid_report_interval, ulong, 0644);
125 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
126
127 /* --------------------------------------------------------------------------
128                               FS Interface (/proc)
129    -------------------------------------------------------------------------- */
130
131 static struct proc_dir_entry *acpi_button_dir;
132 static struct proc_dir_entry *acpi_lid_dir;
133
134 static int acpi_lid_evaluate_state(struct acpi_device *device)
135 {
136         unsigned long long lid_state;
137         acpi_status status;
138
139         status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
140         if (ACPI_FAILURE(status))
141                 return -ENODEV;
142
143         return lid_state ? 1 : 0;
144 }
145
146 static int acpi_lid_notify_state(struct acpi_device *device, int state)
147 {
148         struct acpi_button *button = acpi_driver_data(device);
149         int ret;
150         ktime_t next_report;
151         bool do_update;
152
153         /*
154          * In lid_init_state=ignore mode, if user opens/closes lid
155          * frequently with "open" missing, and "last_time" is also updated
156          * frequently, "close" cannot be delivered to the userspace.
157          * So "last_time" is only updated after a timeout or an actual
158          * switch.
159          */
160         if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
161             button->last_state != !!state)
162                 do_update = true;
163         else
164                 do_update = false;
165
166         next_report = ktime_add(button->last_time,
167                                 ms_to_ktime(lid_report_interval));
168         if (button->last_state == !!state &&
169             ktime_after(ktime_get(), next_report)) {
170                 /* Complain the buggy firmware */
171                 pr_warn_once("The lid device is not compliant to SW_LID.\n");
172
173                 /*
174                  * Send the unreliable complement switch event:
175                  *
176                  * On most platforms, the lid device is reliable. However
177                  * there are exceptions:
178                  * 1. Platforms returning initial lid state as "close" by
179                  *    default after booting/resuming:
180                  *     https://bugzilla.kernel.org/show_bug.cgi?id=89211
181                  *     https://bugzilla.kernel.org/show_bug.cgi?id=106151
182                  * 2. Platforms never reporting "open" events:
183                  *     https://bugzilla.kernel.org/show_bug.cgi?id=106941
184                  * On these buggy platforms, the usage model of the ACPI
185                  * lid device actually is:
186                  * 1. The initial returning value of _LID may not be
187                  *    reliable.
188                  * 2. The open event may not be reliable.
189                  * 3. The close event is reliable.
190                  *
191                  * But SW_LID is typed as input switch event, the input
192                  * layer checks if the event is redundant. Hence if the
193                  * state is not switched, the userspace cannot see this
194                  * platform triggered reliable event. By inserting a
195                  * complement switch event, it then is guaranteed that the
196                  * platform triggered reliable one can always be seen by
197                  * the userspace.
198                  */
199                 if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
200                         do_update = true;
201                         /*
202                          * Do generate complement switch event for "close"
203                          * as "close" is reliable and wrong "open" won't
204                          * trigger unexpected behaviors.
205                          * Do not generate complement switch event for
206                          * "open" as "open" is not reliable and wrong
207                          * "close" will trigger unexpected behaviors.
208                          */
209                         if (!state) {
210                                 input_report_switch(button->input,
211                                                     SW_LID, state);
212                                 input_sync(button->input);
213                         }
214                 }
215         }
216         /* Send the platform triggered reliable event */
217         if (do_update) {
218                 acpi_handle_debug(device->handle, "ACPI LID %s\n",
219                                   state ? "open" : "closed");
220                 input_report_switch(button->input, SW_LID, !state);
221                 input_sync(button->input);
222                 button->last_state = !!state;
223                 button->last_time = ktime_get();
224         }
225
226         ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
227         if (ret == NOTIFY_DONE)
228                 ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
229                                                    device);
230         if (ret == NOTIFY_DONE || ret == NOTIFY_OK) {
231                 /*
232                  * It is also regarded as success if the notifier_chain
233                  * returns NOTIFY_OK or NOTIFY_DONE.
234                  */
235                 ret = 0;
236         }
237         return ret;
238 }
239
240 static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq,
241                                                      void *offset)
242 {
243         struct acpi_device *device = seq->private;
244         int state;
245
246         state = acpi_lid_evaluate_state(device);
247         seq_printf(seq, "state:      %s\n",
248                    state < 0 ? "unsupported" : (state ? "open" : "closed"));
249         return 0;
250 }
251
252 static int acpi_button_add_fs(struct acpi_device *device)
253 {
254         struct acpi_button *button = acpi_driver_data(device);
255         struct proc_dir_entry *entry = NULL;
256         int ret = 0;
257
258         /* procfs I/F for ACPI lid device only */
259         if (button->type != ACPI_BUTTON_TYPE_LID)
260                 return 0;
261
262         if (acpi_button_dir || acpi_lid_dir) {
263                 printk(KERN_ERR PREFIX "More than one Lid device found!\n");
264                 return -EEXIST;
265         }
266
267         /* create /proc/acpi/button */
268         acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
269         if (!acpi_button_dir)
270                 return -ENODEV;
271
272         /* create /proc/acpi/button/lid */
273         acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
274         if (!acpi_lid_dir) {
275                 ret = -ENODEV;
276                 goto remove_button_dir;
277         }
278
279         /* create /proc/acpi/button/lid/LID/ */
280         acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
281         if (!acpi_device_dir(device)) {
282                 ret = -ENODEV;
283                 goto remove_lid_dir;
284         }
285
286         /* create /proc/acpi/button/lid/LID/state */
287         entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO,
288                         acpi_device_dir(device), acpi_button_state_seq_show,
289                         device);
290         if (!entry) {
291                 ret = -ENODEV;
292                 goto remove_dev_dir;
293         }
294
295 done:
296         return ret;
297
298 remove_dev_dir:
299         remove_proc_entry(acpi_device_bid(device),
300                           acpi_lid_dir);
301         acpi_device_dir(device) = NULL;
302 remove_lid_dir:
303         remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
304         acpi_lid_dir = NULL;
305 remove_button_dir:
306         remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
307         acpi_button_dir = NULL;
308         goto done;
309 }
310
311 static int acpi_button_remove_fs(struct acpi_device *device)
312 {
313         struct acpi_button *button = acpi_driver_data(device);
314
315         if (button->type != ACPI_BUTTON_TYPE_LID)
316                 return 0;
317
318         remove_proc_entry(ACPI_BUTTON_FILE_STATE,
319                           acpi_device_dir(device));
320         remove_proc_entry(acpi_device_bid(device),
321                           acpi_lid_dir);
322         acpi_device_dir(device) = NULL;
323         remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
324         acpi_lid_dir = NULL;
325         remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
326         acpi_button_dir = NULL;
327
328         return 0;
329 }
330
331 /* --------------------------------------------------------------------------
332                                 Driver Interface
333    -------------------------------------------------------------------------- */
334 int acpi_lid_notifier_register(struct notifier_block *nb)
335 {
336         return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
337 }
338 EXPORT_SYMBOL(acpi_lid_notifier_register);
339
340 int acpi_lid_notifier_unregister(struct notifier_block *nb)
341 {
342         return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
343 }
344 EXPORT_SYMBOL(acpi_lid_notifier_unregister);
345
346 int acpi_lid_open(void)
347 {
348         if (!lid_device)
349                 return -ENODEV;
350
351         return acpi_lid_evaluate_state(lid_device);
352 }
353 EXPORT_SYMBOL(acpi_lid_open);
354
355 static int acpi_lid_update_state(struct acpi_device *device,
356                                  bool signal_wakeup)
357 {
358         int state;
359
360         state = acpi_lid_evaluate_state(device);
361         if (state < 0)
362                 return state;
363
364         if (state && signal_wakeup)
365                 acpi_pm_wakeup_event(&device->dev);
366
367         return acpi_lid_notify_state(device, state);
368 }
369
370 static void acpi_lid_initialize_state(struct acpi_device *device)
371 {
372         switch (lid_init_state) {
373         case ACPI_BUTTON_LID_INIT_OPEN:
374                 (void)acpi_lid_notify_state(device, 1);
375                 break;
376         case ACPI_BUTTON_LID_INIT_METHOD:
377                 (void)acpi_lid_update_state(device, false);
378                 break;
379         case ACPI_BUTTON_LID_INIT_IGNORE:
380         default:
381                 break;
382         }
383 }
384
385 static void acpi_button_notify(struct acpi_device *device, u32 event)
386 {
387         struct acpi_button *button = acpi_driver_data(device);
388         struct input_dev *input;
389         int users;
390
391         switch (event) {
392         case ACPI_FIXED_HARDWARE_EVENT:
393                 event = ACPI_BUTTON_NOTIFY_STATUS;
394                 /* fall through */
395         case ACPI_BUTTON_NOTIFY_STATUS:
396                 input = button->input;
397                 if (button->type == ACPI_BUTTON_TYPE_LID) {
398                         mutex_lock(&button->input->mutex);
399                         users = button->input->users;
400                         mutex_unlock(&button->input->mutex);
401                         if (users)
402                                 acpi_lid_update_state(device, true);
403                 } else {
404                         int keycode;
405
406                         acpi_pm_wakeup_event(&device->dev);
407                         if (button->suspended)
408                                 break;
409
410                         keycode = test_bit(KEY_SLEEP, input->keybit) ?
411                                                 KEY_SLEEP : KEY_POWER;
412                         input_report_key(input, keycode, 1);
413                         input_sync(input);
414                         input_report_key(input, keycode, 0);
415                         input_sync(input);
416
417                         acpi_bus_generate_netlink_event(
418                                         device->pnp.device_class,
419                                         dev_name(&device->dev),
420                                         event, ++button->pushed);
421                 }
422                 break;
423         default:
424                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
425                                   "Unsupported event [0x%x]\n", event));
426                 break;
427         }
428 }
429
430 #ifdef CONFIG_PM_SLEEP
431 static int acpi_button_suspend(struct device *dev)
432 {
433         struct acpi_device *device = to_acpi_device(dev);
434         struct acpi_button *button = acpi_driver_data(device);
435
436         button->suspended = true;
437         return 0;
438 }
439
440 static int acpi_button_resume(struct device *dev)
441 {
442         struct acpi_device *device = to_acpi_device(dev);
443         struct acpi_button *button = acpi_driver_data(device);
444
445         button->suspended = false;
446         if (button->type == ACPI_BUTTON_TYPE_LID && button->input->users) {
447                 button->last_state = !!acpi_lid_evaluate_state(device);
448                 button->last_time = ktime_get();
449                 acpi_lid_initialize_state(device);
450         }
451         return 0;
452 }
453 #endif
454
455 static int acpi_lid_input_open(struct input_dev *input)
456 {
457         struct acpi_device *device = input_get_drvdata(input);
458         struct acpi_button *button = acpi_driver_data(device);
459
460         button->last_state = !!acpi_lid_evaluate_state(device);
461         button->last_time = ktime_get();
462         acpi_lid_initialize_state(device);
463
464         return 0;
465 }
466
467 static int acpi_button_add(struct acpi_device *device)
468 {
469         struct acpi_button *button;
470         struct input_dev *input;
471         const char *hid = acpi_device_hid(device);
472         char *name, *class;
473         int error;
474
475         if (!strcmp(hid, ACPI_BUTTON_HID_LID) && dmi_check_system(lid_blacklst))
476                 return -ENODEV;
477
478         button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
479         if (!button)
480                 return -ENOMEM;
481
482         device->driver_data = button;
483
484         button->input = input = input_allocate_device();
485         if (!input) {
486                 error = -ENOMEM;
487                 goto err_free_button;
488         }
489
490         name = acpi_device_name(device);
491         class = acpi_device_class(device);
492
493         if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
494             !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
495                 button->type = ACPI_BUTTON_TYPE_POWER;
496                 strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
497                 sprintf(class, "%s/%s",
498                         ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
499         } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
500                    !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
501                 button->type = ACPI_BUTTON_TYPE_SLEEP;
502                 strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
503                 sprintf(class, "%s/%s",
504                         ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
505         } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
506                 button->type = ACPI_BUTTON_TYPE_LID;
507                 strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
508                 sprintf(class, "%s/%s",
509                         ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
510                 input->open = acpi_lid_input_open;
511         } else {
512                 printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
513                 error = -ENODEV;
514                 goto err_free_input;
515         }
516
517         error = acpi_button_add_fs(device);
518         if (error)
519                 goto err_free_input;
520
521         snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
522
523         input->name = name;
524         input->phys = button->phys;
525         input->id.bustype = BUS_HOST;
526         input->id.product = button->type;
527         input->dev.parent = &device->dev;
528
529         switch (button->type) {
530         case ACPI_BUTTON_TYPE_POWER:
531                 input_set_capability(input, EV_KEY, KEY_POWER);
532                 break;
533
534         case ACPI_BUTTON_TYPE_SLEEP:
535                 input_set_capability(input, EV_KEY, KEY_SLEEP);
536                 break;
537
538         case ACPI_BUTTON_TYPE_LID:
539                 input_set_capability(input, EV_SW, SW_LID);
540                 break;
541         }
542
543         input_set_drvdata(input, device);
544         error = input_register_device(input);
545         if (error)
546                 goto err_remove_fs;
547         if (button->type == ACPI_BUTTON_TYPE_LID) {
548                 /*
549                  * This assumes there's only one lid device, or if there are
550                  * more we only care about the last one...
551                  */
552                 lid_device = device;
553         }
554
555         device_init_wakeup(&device->dev, true);
556         printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
557         return 0;
558
559  err_remove_fs:
560         acpi_button_remove_fs(device);
561  err_free_input:
562         input_free_device(input);
563  err_free_button:
564         kfree(button);
565         return error;
566 }
567
568 static int acpi_button_remove(struct acpi_device *device)
569 {
570         struct acpi_button *button = acpi_driver_data(device);
571
572         acpi_button_remove_fs(device);
573         input_unregister_device(button->input);
574         kfree(button);
575         return 0;
576 }
577
578 static int param_set_lid_init_state(const char *val,
579                                     const struct kernel_param *kp)
580 {
581         int result = 0;
582
583         if (!strncmp(val, "open", sizeof("open") - 1)) {
584                 lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
585                 pr_info("Notify initial lid state as open\n");
586         } else if (!strncmp(val, "method", sizeof("method") - 1)) {
587                 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
588                 pr_info("Notify initial lid state with _LID return value\n");
589         } else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
590                 lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
591                 pr_info("Do not notify initial lid state\n");
592         } else
593                 result = -EINVAL;
594         return result;
595 }
596
597 static int param_get_lid_init_state(char *buffer,
598                                     const struct kernel_param *kp)
599 {
600         switch (lid_init_state) {
601         case ACPI_BUTTON_LID_INIT_OPEN:
602                 return sprintf(buffer, "open");
603         case ACPI_BUTTON_LID_INIT_METHOD:
604                 return sprintf(buffer, "method");
605         case ACPI_BUTTON_LID_INIT_IGNORE:
606                 return sprintf(buffer, "ignore");
607         default:
608                 return sprintf(buffer, "invalid");
609         }
610         return 0;
611 }
612
613 module_param_call(lid_init_state,
614                   param_set_lid_init_state, param_get_lid_init_state,
615                   NULL, 0644);
616 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
617
618 static int acpi_button_register_driver(struct acpi_driver *driver)
619 {
620         /*
621          * Modules such as nouveau.ko and i915.ko have a link time dependency
622          * on acpi_lid_open(), and would therefore not be loadable on ACPI
623          * capable kernels booted in non-ACPI mode if the return value of
624          * acpi_bus_register_driver() is returned from here with ACPI disabled
625          * when this driver is built as a module.
626          */
627         if (acpi_disabled)
628                 return 0;
629
630         return acpi_bus_register_driver(driver);
631 }
632
633 static void acpi_button_unregister_driver(struct acpi_driver *driver)
634 {
635         if (!acpi_disabled)
636                 acpi_bus_unregister_driver(driver);
637 }
638
639 module_driver(acpi_button_driver, acpi_button_register_driver,
640                acpi_button_unregister_driver);