2 * button.c - ACPI Button Driver
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
19 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
22 #define pr_fmt(fmt) "ACPI: button: " fmt
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>
35 #define PREFIX "ACPI: "
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
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
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
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
58 #define ACPI_BUTTON_LID_INIT_IGNORE 0x00
59 #define ACPI_BUTTON_LID_INIT_OPEN 0x01
60 #define ACPI_BUTTON_LID_INIT_METHOD 0x02
62 #define _COMPONENT ACPI_BUTTON_COMPONENT
63 ACPI_MODULE_NAME("button");
65 MODULE_AUTHOR("Paul Diefenbaugh");
66 MODULE_DESCRIPTION("ACPI Button Driver");
67 MODULE_LICENSE("GPL");
69 static 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},
77 MODULE_DEVICE_TABLE(acpi, button_device_ids);
79 static int acpi_button_add(struct acpi_device *device);
80 static int acpi_button_remove(struct acpi_device *device);
81 static void acpi_button_notify(struct acpi_device *device, u32 event);
83 #ifdef CONFIG_PM_SLEEP
84 static int acpi_button_suspend(struct device *dev);
85 static int acpi_button_resume(struct device *dev);
87 #define acpi_button_suspend NULL
88 #define acpi_button_resume NULL
90 static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
92 static struct acpi_driver acpi_button_driver = {
94 .class = ACPI_BUTTON_CLASS,
95 .ids = button_device_ids,
97 .add = acpi_button_add,
98 .remove = acpi_button_remove,
99 .notify = acpi_button_notify,
101 .drv.pm = &acpi_button_pm,
106 struct input_dev *input;
107 char phys[32]; /* for input device */
108 unsigned long pushed;
114 static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
115 static struct acpi_device *lid_device;
116 static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
118 static unsigned long lid_report_interval __read_mostly = 500;
119 module_param(lid_report_interval, ulong, 0644);
120 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
122 /* --------------------------------------------------------------------------
124 -------------------------------------------------------------------------- */
126 static struct proc_dir_entry *acpi_button_dir;
127 static struct proc_dir_entry *acpi_lid_dir;
129 static int acpi_lid_evaluate_state(struct acpi_device *device)
131 unsigned long long lid_state;
134 status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
135 if (ACPI_FAILURE(status))
138 return lid_state ? 1 : 0;
141 static int acpi_lid_notify_state(struct acpi_device *device, int state)
143 struct acpi_button *button = acpi_driver_data(device);
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
155 if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
156 button->last_state != !!state)
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");
169 * Send the unreliable complement switch event:
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
183 * 2. The open event may not be reliable.
184 * 3. The close event is reliable.
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
194 if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
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.
205 input_report_switch(button->input,
207 input_sync(button->input);
211 /* Send the platform triggered reliable event */
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();
220 acpi_pm_wakeup_event(&device->dev);
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,
226 if (ret == NOTIFY_DONE || ret == NOTIFY_OK) {
228 * It is also regarded as success if the notifier_chain
229 * returns NOTIFY_OK or NOTIFY_DONE.
236 static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
238 struct acpi_device *device = seq->private;
241 state = acpi_lid_evaluate_state(device);
242 seq_printf(seq, "state: %s\n",
243 state < 0 ? "unsupported" : (state ? "open" : "closed"));
247 static int acpi_button_state_open_fs(struct inode *inode, struct file *file)
249 return single_open(file, acpi_button_state_seq_show, PDE_DATA(inode));
252 static const struct file_operations acpi_button_state_fops = {
253 .owner = THIS_MODULE,
254 .open = acpi_button_state_open_fs,
257 .release = single_release,
260 static int acpi_button_add_fs(struct acpi_device *device)
262 struct acpi_button *button = acpi_driver_data(device);
263 struct proc_dir_entry *entry = NULL;
266 /* procfs I/F for ACPI lid device only */
267 if (button->type != ACPI_BUTTON_TYPE_LID)
270 if (acpi_button_dir || acpi_lid_dir) {
271 printk(KERN_ERR PREFIX "More than one Lid device found!\n");
275 /* create /proc/acpi/button */
276 acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
277 if (!acpi_button_dir)
280 /* create /proc/acpi/button/lid */
281 acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
284 goto remove_button_dir;
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)) {
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);
307 remove_proc_entry(acpi_device_bid(device),
309 acpi_device_dir(device) = NULL;
311 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
314 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
315 acpi_button_dir = NULL;
319 static int acpi_button_remove_fs(struct acpi_device *device)
321 struct acpi_button *button = acpi_driver_data(device);
323 if (button->type != ACPI_BUTTON_TYPE_LID)
326 remove_proc_entry(ACPI_BUTTON_FILE_STATE,
327 acpi_device_dir(device));
328 remove_proc_entry(acpi_device_bid(device),
330 acpi_device_dir(device) = NULL;
331 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
333 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
334 acpi_button_dir = NULL;
339 /* --------------------------------------------------------------------------
341 -------------------------------------------------------------------------- */
342 int acpi_lid_notifier_register(struct notifier_block *nb)
344 return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
346 EXPORT_SYMBOL(acpi_lid_notifier_register);
348 int acpi_lid_notifier_unregister(struct notifier_block *nb)
350 return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
352 EXPORT_SYMBOL(acpi_lid_notifier_unregister);
354 int acpi_lid_open(void)
359 return acpi_lid_evaluate_state(lid_device);
361 EXPORT_SYMBOL(acpi_lid_open);
363 static int acpi_lid_update_state(struct acpi_device *device)
367 state = acpi_lid_evaluate_state(device);
371 return acpi_lid_notify_state(device, state);
374 static void acpi_lid_initialize_state(struct acpi_device *device)
376 switch (lid_init_state) {
377 case ACPI_BUTTON_LID_INIT_OPEN:
378 (void)acpi_lid_notify_state(device, 1);
380 case ACPI_BUTTON_LID_INIT_METHOD:
381 (void)acpi_lid_update_state(device);
383 case ACPI_BUTTON_LID_INIT_IGNORE:
389 static void acpi_button_notify(struct acpi_device *device, u32 event)
391 struct acpi_button *button = acpi_driver_data(device);
392 struct input_dev *input;
396 case ACPI_FIXED_HARDWARE_EVENT:
397 event = ACPI_BUTTON_NOTIFY_STATUS;
399 case ACPI_BUTTON_NOTIFY_STATUS:
400 input = button->input;
401 if (button->type == ACPI_BUTTON_TYPE_LID) {
402 mutex_lock(&button->input->mutex);
403 users = button->input->users;
404 mutex_unlock(&button->input->mutex);
406 acpi_lid_update_state(device);
410 acpi_pm_wakeup_event(&device->dev);
411 if (button->suspended)
414 keycode = test_bit(KEY_SLEEP, input->keybit) ?
415 KEY_SLEEP : KEY_POWER;
416 input_report_key(input, keycode, 1);
418 input_report_key(input, keycode, 0);
421 acpi_bus_generate_netlink_event(
422 device->pnp.device_class,
423 dev_name(&device->dev),
424 event, ++button->pushed);
428 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
429 "Unsupported event [0x%x]\n", event));
434 #ifdef CONFIG_PM_SLEEP
435 static int acpi_button_suspend(struct device *dev)
437 struct acpi_device *device = to_acpi_device(dev);
438 struct acpi_button *button = acpi_driver_data(device);
440 button->suspended = true;
444 static int acpi_button_resume(struct device *dev)
446 struct acpi_device *device = to_acpi_device(dev);
447 struct acpi_button *button = acpi_driver_data(device);
449 button->suspended = false;
450 if (button->type == ACPI_BUTTON_TYPE_LID && button->input->users)
451 acpi_lid_initialize_state(device);
456 static int acpi_lid_input_open(struct input_dev *input)
458 struct acpi_device *device = input_get_drvdata(input);
459 struct acpi_button *button = acpi_driver_data(device);
461 button->last_state = !!acpi_lid_evaluate_state(device);
462 button->last_time = ktime_get();
463 acpi_lid_initialize_state(device);
468 static int acpi_button_add(struct acpi_device *device)
470 struct acpi_button *button;
471 struct input_dev *input;
472 const char *hid = acpi_device_hid(device);
476 button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
480 device->driver_data = button;
482 button->input = input = input_allocate_device();
485 goto err_free_button;
488 name = acpi_device_name(device);
489 class = acpi_device_class(device);
491 if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
492 !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
493 button->type = ACPI_BUTTON_TYPE_POWER;
494 strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
495 sprintf(class, "%s/%s",
496 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
497 } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
498 !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
499 button->type = ACPI_BUTTON_TYPE_SLEEP;
500 strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
501 sprintf(class, "%s/%s",
502 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
503 } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
504 button->type = ACPI_BUTTON_TYPE_LID;
505 strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
506 sprintf(class, "%s/%s",
507 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
508 input->open = acpi_lid_input_open;
510 printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
515 error = acpi_button_add_fs(device);
519 snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
522 input->phys = button->phys;
523 input->id.bustype = BUS_HOST;
524 input->id.product = button->type;
525 input->dev.parent = &device->dev;
527 switch (button->type) {
528 case ACPI_BUTTON_TYPE_POWER:
529 input_set_capability(input, EV_KEY, KEY_POWER);
532 case ACPI_BUTTON_TYPE_SLEEP:
533 input_set_capability(input, EV_KEY, KEY_SLEEP);
536 case ACPI_BUTTON_TYPE_LID:
537 input_set_capability(input, EV_SW, SW_LID);
541 input_set_drvdata(input, device);
542 error = input_register_device(input);
545 if (button->type == ACPI_BUTTON_TYPE_LID) {
547 * This assumes there's only one lid device, or if there are
548 * more we only care about the last one...
553 device_init_wakeup(&device->dev, true);
554 printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
558 acpi_button_remove_fs(device);
560 input_free_device(input);
566 static int acpi_button_remove(struct acpi_device *device)
568 struct acpi_button *button = acpi_driver_data(device);
570 acpi_button_remove_fs(device);
571 input_unregister_device(button->input);
576 static int param_set_lid_init_state(const char *val, struct kernel_param *kp)
580 if (!strncmp(val, "open", sizeof("open") - 1)) {
581 lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
582 pr_info("Notify initial lid state as open\n");
583 } else if (!strncmp(val, "method", sizeof("method") - 1)) {
584 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
585 pr_info("Notify initial lid state with _LID return value\n");
586 } else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
587 lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
588 pr_info("Do not notify initial lid state\n");
594 static int param_get_lid_init_state(char *buffer, struct kernel_param *kp)
596 switch (lid_init_state) {
597 case ACPI_BUTTON_LID_INIT_OPEN:
598 return sprintf(buffer, "open");
599 case ACPI_BUTTON_LID_INIT_METHOD:
600 return sprintf(buffer, "method");
601 case ACPI_BUTTON_LID_INIT_IGNORE:
602 return sprintf(buffer, "ignore");
604 return sprintf(buffer, "invalid");
609 module_param_call(lid_init_state,
610 param_set_lid_init_state, param_get_lid_init_state,
612 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
614 module_acpi_driver(acpi_button_driver);