source: src/linux/universal/linux-4.9/drivers/acpi/button.c @ 31859

Last change on this file since 31859 was 31859, checked in by brainslayer, 11 days ago

kernel update

File size: 16.3 KB
Line 
1/*
2 *  button.c - ACPI Button Driver
3 *
4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 *  This program is free software; you can redistribute it and/or modify
10 *  it under the terms of the GNU General Public License as published by
11 *  the Free Software Foundation; either version 2 of the License, or (at
12 *  your option) any later version.
13 *
14 *  This program is distributed in the hope that it will be useful, but
15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 *  General Public License for more details.
18 *
19 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20 */
21
22#define pr_fmt(fmt) "ACPI : button: " fmt
23
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/types.h>
28#include <linux/proc_fs.h>
29#include <linux/seq_file.h>
30#include <linux/input.h>
31#include <linux/slab.h>
32#include <linux/acpi.h>
33#include <acpi/button.h>
34
35#define PREFIX "ACPI: "
36
37#define ACPI_BUTTON_CLASS               "button"
38#define ACPI_BUTTON_FILE_INFO           "info"
39#define ACPI_BUTTON_FILE_STATE          "state"
40#define ACPI_BUTTON_TYPE_UNKNOWN        0x00
41#define ACPI_BUTTON_NOTIFY_STATUS       0x80
42
43#define ACPI_BUTTON_SUBCLASS_POWER      "power"
44#define ACPI_BUTTON_HID_POWER           "PNP0C0C"
45#define ACPI_BUTTON_DEVICE_NAME_POWER   "Power Button"
46#define ACPI_BUTTON_TYPE_POWER          0x01
47
48#define ACPI_BUTTON_SUBCLASS_SLEEP      "sleep"
49#define ACPI_BUTTON_HID_SLEEP           "PNP0C0E"
50#define ACPI_BUTTON_DEVICE_NAME_SLEEP   "Sleep Button"
51#define ACPI_BUTTON_TYPE_SLEEP          0x03
52
53#define ACPI_BUTTON_SUBCLASS_LID        "lid"
54#define ACPI_BUTTON_HID_LID             "PNP0C0D"
55#define ACPI_BUTTON_DEVICE_NAME_LID     "Lid Switch"
56#define ACPI_BUTTON_TYPE_LID            0x05
57
58#define ACPI_BUTTON_LID_INIT_IGNORE     0x00
59#define ACPI_BUTTON_LID_INIT_OPEN       0x01
60#define ACPI_BUTTON_LID_INIT_METHOD     0x02
61
62#define _COMPONENT              ACPI_BUTTON_COMPONENT
63ACPI_MODULE_NAME("button");
64
65MODULE_AUTHOR("Paul Diefenbaugh");
66MODULE_DESCRIPTION("ACPI Button Driver");
67MODULE_LICENSE("GPL");
68
69static const struct acpi_device_id button_device_ids[] = {
70        {ACPI_BUTTON_HID_LID,    0},
71        {ACPI_BUTTON_HID_SLEEP,  0},
72        {ACPI_BUTTON_HID_SLEEPF, 0},
73        {ACPI_BUTTON_HID_POWER,  0},
74        {ACPI_BUTTON_HID_POWERF, 0},
75        {"", 0},
76};
77MODULE_DEVICE_TABLE(acpi, button_device_ids);
78
79static int acpi_button_add(struct acpi_device *device);
80static int acpi_button_remove(struct acpi_device *device);
81static void acpi_button_notify(struct acpi_device *device, u32 event);
82
83#ifdef CONFIG_PM_SLEEP
84static int acpi_button_suspend(struct device *dev);
85static int acpi_button_resume(struct device *dev);
86#else
87#define acpi_button_suspend NULL
88#define acpi_button_resume NULL
89#endif
90static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
91
92static struct acpi_driver acpi_button_driver = {
93        .name = "button",
94        .class = ACPI_BUTTON_CLASS,
95        .ids = button_device_ids,
96        .ops = {
97                .add = acpi_button_add,
98                .remove = acpi_button_remove,
99                .notify = acpi_button_notify,
100        },
101        .drv.pm = &acpi_button_pm,
102};
103
104struct acpi_button {
105        unsigned int type;
106        struct input_dev *input;
107        char phys[32];                  /* for input device */
108        unsigned long pushed;
109        int last_state;
110        ktime_t last_time;
111        bool suspended;
112};
113
114static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
115static struct acpi_device *lid_device;
116static u8 lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
117
118static unsigned long lid_report_interval __read_mostly = 500;
119module_param(lid_report_interval, ulong, 0644);
120MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
121
122/* --------------------------------------------------------------------------
123                              FS Interface (/proc)
124   -------------------------------------------------------------------------- */
125
126static struct proc_dir_entry *acpi_button_dir;
127static struct proc_dir_entry *acpi_lid_dir;
128
129static int acpi_lid_evaluate_state(struct acpi_device *device)
130{
131        unsigned long long lid_state;
132        acpi_status status;
133
134        status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
135        if (ACPI_FAILURE(status))
136                return -ENODEV;
137
138        return lid_state ? 1 : 0;
139}
140
141static int acpi_lid_notify_state(struct acpi_device *device, int state)
142{
143        struct acpi_button *button = acpi_driver_data(device);
144        int ret;
145        ktime_t next_report;
146        bool do_update;
147
148        /*
149         * In lid_init_state=ignore mode, if user opens/closes lid
150         * frequently with "open" missing, and "last_time" is also updated
151         * frequently, "close" cannot be delivered to the userspace.
152         * So "last_time" is only updated after a timeout or an actual
153         * switch.
154         */
155        if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
156            button->last_state != !!state)
157                do_update = true;
158        else
159                do_update = false;
160
161        next_report = ktime_add(button->last_time,
162                                ms_to_ktime(lid_report_interval));
163        if (button->last_state == !!state &&
164            ktime_after(ktime_get(), next_report)) {
165                /* Complain the buggy firmware */
166                pr_warn_once("The lid device is not compliant to SW_LID.\n");
167
168                /*
169                 * Send the unreliable complement switch event:
170                 *
171                 * On most platforms, the lid device is reliable. However
172                 * there are exceptions:
173                 * 1. Platforms returning initial lid state as "close" by
174                 *    default after booting/resuming:
175                 *     https://bugzilla.kernel.org/show_bug.cgi?id=89211
176                 *     https://bugzilla.kernel.org/show_bug.cgi?id=106151
177                 * 2. Platforms never reporting "open" events:
178                 *     https://bugzilla.kernel.org/show_bug.cgi?id=106941
179                 * On these buggy platforms, the usage model of the ACPI
180                 * lid device actually is:
181                 * 1. The initial returning value of _LID may not be
182                 *    reliable.
183                 * 2. The open event may not be reliable.
184                 * 3. The close event is reliable.
185                 *
186                 * But SW_LID is typed as input switch event, the input
187                 * layer checks if the event is redundant. Hence if the
188                 * state is not switched, the userspace cannot see this
189                 * platform triggered reliable event. By inserting a
190                 * complement switch event, it then is guaranteed that the
191                 * platform triggered reliable one can always be seen by
192                 * the userspace.
193                 */
194                if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
195                        do_update = true;
196                        /*
197                         * Do generate complement switch event for "close"
198                         * as "close" is reliable and wrong "open" won't
199                         * trigger unexpected behaviors.
200                         * Do not generate complement switch event for
201                         * "open" as "open" is not reliable and wrong
202                         * "close" will trigger unexpected behaviors.
203                         */
204                        if (!state) {
205                                input_report_switch(button->input,
206                                                    SW_LID, state);
207                                input_sync(button->input);
208                        }
209                }
210        }
211        /* Send the platform triggered reliable event */
212        if (do_update) {
213                input_report_switch(button->input, SW_LID, !state);
214                input_sync(button->input);
215                button->last_state = !!state;
216                button->last_time = ktime_get();
217        }
218
219        if (state)
220                pm_wakeup_event(&device->dev, 0);
221
222        ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
223        if (ret == NOTIFY_DONE)
224                ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
225                                                   device);
226        if (ret == NOTIFY_DONE || ret == NOTIFY_OK) {
227                /*
228                 * It is also regarded as success if the notifier_chain
229                 * returns NOTIFY_OK or NOTIFY_DONE.
230                 */
231                ret = 0;
232        }
233        return ret;
234}
235
236static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
237{
238        struct acpi_device *device = seq->private;
239        int state;
240
241        state = acpi_lid_evaluate_state(device);
242        seq_printf(seq, "state:      %s\n",
243                   state < 0 ? "unsupported" : (state ? "open" : "closed"));
244        return 0;
245}
246
247static int acpi_button_state_open_fs(struct inode *inode, struct file *file)
248{
249        return single_open(file, acpi_button_state_seq_show, PDE_DATA(inode));
250}
251
252static const struct file_operations acpi_button_state_fops = {
253        .owner = THIS_MODULE,
254        .open = acpi_button_state_open_fs,
255        .read = seq_read,
256        .llseek = seq_lseek,
257        .release = single_release,
258};
259
260static int acpi_button_add_fs(struct acpi_device *device)
261{
262        struct acpi_button *button = acpi_driver_data(device);
263        struct proc_dir_entry *entry = NULL;
264        int ret = 0;
265
266        /* procfs I/F for ACPI lid device only */
267        if (button->type != ACPI_BUTTON_TYPE_LID)
268                return 0;
269
270        if (acpi_button_dir || acpi_lid_dir) {
271                printk(KERN_ERR PREFIX "More than one Lid device found!\n");
272                return -EEXIST;
273        }
274
275        /* create /proc/acpi/button */
276        acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
277        if (!acpi_button_dir)
278                return -ENODEV;
279
280        /* create /proc/acpi/button/lid */
281        acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
282        if (!acpi_lid_dir) {
283                ret = -ENODEV;
284                goto remove_button_dir;
285        }
286
287        /* create /proc/acpi/button/lid/LID/ */
288        acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
289        if (!acpi_device_dir(device)) {
290                ret = -ENODEV;
291                goto remove_lid_dir;
292        }
293
294        /* create /proc/acpi/button/lid/LID/state */
295        entry = proc_create_data(ACPI_BUTTON_FILE_STATE,
296                                 S_IRUGO, acpi_device_dir(device),
297                                 &acpi_button_state_fops, device);
298        if (!entry) {
299                ret = -ENODEV;
300                goto remove_dev_dir;
301        }
302
303done:
304        return ret;
305
306remove_dev_dir:
307        remove_proc_entry(acpi_device_bid(device),
308                          acpi_lid_dir);
309        acpi_device_dir(device) = NULL;
310remove_lid_dir:
311        remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
312        acpi_lid_dir = NULL;
313remove_button_dir:
314        remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
315        acpi_button_dir = NULL;
316        goto done;
317}
318
319static int acpi_button_remove_fs(struct acpi_device *device)
320{
321        struct acpi_button *button = acpi_driver_data(device);
322
323        if (button->type != ACPI_BUTTON_TYPE_LID)
324                return 0;
325
326        remove_proc_entry(ACPI_BUTTON_FILE_STATE,
327                          acpi_device_dir(device));
328        remove_proc_entry(acpi_device_bid(device),
329                          acpi_lid_dir);
330        acpi_device_dir(device) = NULL;
331        remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
332        acpi_lid_dir = NULL;
333        remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
334        acpi_button_dir = NULL;
335
336        return 0;
337}
338
339/* --------------------------------------------------------------------------
340                                Driver Interface
341   -------------------------------------------------------------------------- */
342int acpi_lid_notifier_register(struct notifier_block *nb)
343{
344        return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
345}
346EXPORT_SYMBOL(acpi_lid_notifier_register);
347
348int acpi_lid_notifier_unregister(struct notifier_block *nb)
349{
350        return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
351}
352EXPORT_SYMBOL(acpi_lid_notifier_unregister);
353
354int acpi_lid_open(void)
355{
356        if (!lid_device)
357                return -ENODEV;
358
359        return acpi_lid_evaluate_state(lid_device);
360}
361EXPORT_SYMBOL(acpi_lid_open);
362
363static int acpi_lid_update_state(struct acpi_device *device)
364{
365        int state;
366
367        state = acpi_lid_evaluate_state(device);
368        if (state < 0)
369                return state;
370
371        return acpi_lid_notify_state(device, state);
372}
373
374static void acpi_lid_initialize_state(struct acpi_device *device)
375{
376        switch (lid_init_state) {
377        case ACPI_BUTTON_LID_INIT_OPEN:
378                (void)acpi_lid_notify_state(device, 1);
379                break;
380        case ACPI_BUTTON_LID_INIT_METHOD:
381                (void)acpi_lid_update_state(device);
382                break;
383        case ACPI_BUTTON_LID_INIT_IGNORE:
384        default:
385                break;
386        }
387}
388
389static void acpi_button_notify(struct acpi_device *device, u32 event)
390{
391        struct acpi_button *button = acpi_driver_data(device);
392        struct input_dev *input;
393
394        switch (event) {
395        case ACPI_FIXED_HARDWARE_EVENT:
396                event = ACPI_BUTTON_NOTIFY_STATUS;
397                /* fall through */
398        case ACPI_BUTTON_NOTIFY_STATUS:
399                input = button->input;
400                if (button->type == ACPI_BUTTON_TYPE_LID) {
401                        acpi_lid_update_state(device);
402                } else {
403                        int keycode;
404
405                        pm_wakeup_event(&device->dev, 0);
406                        if (button->suspended)
407                                break;
408
409                        keycode = test_bit(KEY_SLEEP, input->keybit) ?
410                                                KEY_SLEEP : KEY_POWER;
411                        input_report_key(input, keycode, 1);
412                        input_sync(input);
413                        input_report_key(input, keycode, 0);
414                        input_sync(input);
415
416                        acpi_bus_generate_netlink_event(
417                                        device->pnp.device_class,
418                                        dev_name(&device->dev),
419                                        event, ++button->pushed);
420                }
421                break;
422        default:
423                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
424                                  "Unsupported event [0x%x]\n", event));
425                break;
426        }
427}
428
429#ifdef CONFIG_PM_SLEEP
430static int acpi_button_suspend(struct device *dev)
431{
432        struct acpi_device *device = to_acpi_device(dev);
433        struct acpi_button *button = acpi_driver_data(device);
434
435        button->suspended = true;
436        return 0;
437}
438
439static int acpi_button_resume(struct device *dev)
440{
441        struct acpi_device *device = to_acpi_device(dev);
442        struct acpi_button *button = acpi_driver_data(device);
443
444        button->suspended = false;
445        if (button->type == ACPI_BUTTON_TYPE_LID)
446                acpi_lid_initialize_state(device);
447        return 0;
448}
449#endif
450
451static int acpi_button_add(struct acpi_device *device)
452{
453        struct acpi_button *button;
454        struct input_dev *input;
455        const char *hid = acpi_device_hid(device);
456        char *name, *class;
457        int error;
458
459        button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
460        if (!button)
461                return -ENOMEM;
462
463        device->driver_data = button;
464
465        button->input = input = input_allocate_device();
466        if (!input) {
467                error = -ENOMEM;
468                goto err_free_button;
469        }
470
471        name = acpi_device_name(device);
472        class = acpi_device_class(device);
473
474        if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
475            !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
476                button->type = ACPI_BUTTON_TYPE_POWER;
477                strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
478                sprintf(class, "%s/%s",
479                        ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
480        } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
481                   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
482                button->type = ACPI_BUTTON_TYPE_SLEEP;
483                strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
484                sprintf(class, "%s/%s",
485                        ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
486        } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
487                button->type = ACPI_BUTTON_TYPE_LID;
488                strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
489                sprintf(class, "%s/%s",
490                        ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
491                button->last_state = !!acpi_lid_evaluate_state(device);
492                button->last_time = ktime_get();
493        } else {
494                printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
495                error = -ENODEV;
496                goto err_free_input;
497        }
498
499        error = acpi_button_add_fs(device);
500        if (error)
501                goto err_free_input;
502
503        snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
504
505        input->name = name;
506        input->phys = button->phys;
507        input->id.bustype = BUS_HOST;
508        input->id.product = button->type;
509        input->dev.parent = &device->dev;
510
511        switch (button->type) {
512        case ACPI_BUTTON_TYPE_POWER:
513                input_set_capability(input, EV_KEY, KEY_POWER);
514                break;
515
516        case ACPI_BUTTON_TYPE_SLEEP:
517                input_set_capability(input, EV_KEY, KEY_SLEEP);
518                break;
519
520        case ACPI_BUTTON_TYPE_LID:
521                input_set_capability(input, EV_SW, SW_LID);
522                break;
523        }
524
525        error = input_register_device(input);
526        if (error)
527                goto err_remove_fs;
528        if (button->type == ACPI_BUTTON_TYPE_LID) {
529                acpi_lid_initialize_state(device);
530                /*
531                 * This assumes there's only one lid device, or if there are
532                 * more we only care about the last one...
533                 */
534                lid_device = device;
535        }
536
537        printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
538        return 0;
539
540 err_remove_fs:
541        acpi_button_remove_fs(device);
542 err_free_input:
543        input_free_device(input);
544 err_free_button:
545        kfree(button);
546        return error;
547}
548
549static int acpi_button_remove(struct acpi_device *device)
550{
551        struct acpi_button *button = acpi_driver_data(device);
552
553        acpi_button_remove_fs(device);
554        input_unregister_device(button->input);
555        kfree(button);
556        return 0;
557}
558
559static int param_set_lid_init_state(const char *val, struct kernel_param *kp)
560{
561        int result = 0;
562
563        if (!strncmp(val, "open", sizeof("open") - 1)) {
564                lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
565                pr_info("Notify initial lid state as open\n");
566        } else if (!strncmp(val, "method", sizeof("method") - 1)) {
567                lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
568                pr_info("Notify initial lid state with _LID return value\n");
569        } else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
570                lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
571                pr_info("Do not notify initial lid state\n");
572        } else
573                result = -EINVAL;
574        return result;
575}
576
577static int param_get_lid_init_state(char *buffer, struct kernel_param *kp)
578{
579        switch (lid_init_state) {
580        case ACPI_BUTTON_LID_INIT_OPEN:
581                return sprintf(buffer, "open");
582        case ACPI_BUTTON_LID_INIT_METHOD:
583                return sprintf(buffer, "method");
584        case ACPI_BUTTON_LID_INIT_IGNORE:
585                return sprintf(buffer, "ignore");
586        default:
587                return sprintf(buffer, "invalid");
588        }
589        return 0;
590}
591
592module_param_call(lid_init_state,
593                  param_set_lid_init_state, param_get_lid_init_state,
594                  NULL, 0644);
595MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
596
597module_acpi_driver(acpi_button_driver);
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