1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * button.c - ACPI Button Driver
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
9 #define pr_fmt(fmt) "ACPI: button: " fmt
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>
24 #define PREFIX "ACPI: "
26 #define ACPI_BUTTON_CLASS "button"
27 #define ACPI_BUTTON_FILE_STATE "state"
28 #define ACPI_BUTTON_TYPE_UNKNOWN 0x00
29 #define ACPI_BUTTON_NOTIFY_STATUS 0x80
31 #define ACPI_BUTTON_SUBCLASS_POWER "power"
32 #define ACPI_BUTTON_DEVICE_NAME_POWER "Power Button"
33 #define ACPI_BUTTON_TYPE_POWER 0x01
35 #define ACPI_BUTTON_SUBCLASS_SLEEP "sleep"
36 #define ACPI_BUTTON_DEVICE_NAME_SLEEP "Sleep Button"
37 #define ACPI_BUTTON_TYPE_SLEEP 0x03
39 #define ACPI_BUTTON_SUBCLASS_LID "lid"
40 #define ACPI_BUTTON_DEVICE_NAME_LID "Lid Switch"
41 #define ACPI_BUTTON_TYPE_LID 0x05
44 ACPI_BUTTON_LID_INIT_IGNORE,
45 ACPI_BUTTON_LID_INIT_OPEN,
46 ACPI_BUTTON_LID_INIT_METHOD,
47 ACPI_BUTTON_LID_INIT_DISABLED,
50 static const char * const lid_init_state_str[] = {
51 [ACPI_BUTTON_LID_INIT_IGNORE] = "ignore",
52 [ACPI_BUTTON_LID_INIT_OPEN] = "open",
53 [ACPI_BUTTON_LID_INIT_METHOD] = "method",
54 [ACPI_BUTTON_LID_INIT_DISABLED] = "disabled",
57 #define _COMPONENT ACPI_BUTTON_COMPONENT
58 ACPI_MODULE_NAME("button");
60 MODULE_AUTHOR("Paul Diefenbaugh");
61 MODULE_DESCRIPTION("ACPI Button Driver");
62 MODULE_LICENSE("GPL");
64 static const struct acpi_device_id button_device_ids[] = {
65 {ACPI_BUTTON_HID_LID, 0},
66 {ACPI_BUTTON_HID_SLEEP, 0},
67 {ACPI_BUTTON_HID_SLEEPF, 0},
68 {ACPI_BUTTON_HID_POWER, 0},
69 {ACPI_BUTTON_HID_POWERF, 0},
72 MODULE_DEVICE_TABLE(acpi, button_device_ids);
74 /* Please keep this list sorted alphabetically by vendor and model */
75 static const struct dmi_system_id dmi_lid_quirks[] = {
77 /* GP-electronic T701, _LID method points to a floating GPIO */
79 DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
80 DMI_MATCH(DMI_PRODUCT_NAME, "T701"),
81 DMI_MATCH(DMI_BIOS_VERSION, "BYT70A.YNCHENG.WIN.007"),
83 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
86 /* Nextbook Ares 8A tablet, _LID device always reports lid closed */
88 DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
89 DMI_MATCH(DMI_PRODUCT_NAME, "CherryTrail"),
90 DMI_MATCH(DMI_BIOS_VERSION, "M882"),
92 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
96 * Medion Akoya E2215T, notification of the LID device only
97 * happens on close, not on open and _LID always returns closed.
100 DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
101 DMI_MATCH(DMI_PRODUCT_NAME, "E2215T"),
103 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
107 * Medion Akoya E2228T, notification of the LID device only
108 * happens on close, not on open and _LID always returns closed.
111 DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
112 DMI_MATCH(DMI_PRODUCT_NAME, "E2228T"),
114 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
118 * Razer Blade Stealth 13 late 2019, notification of the LID device
119 * only happens on close, not on open and _LID always returns closed.
122 DMI_MATCH(DMI_SYS_VENDOR, "Razer"),
123 DMI_MATCH(DMI_PRODUCT_NAME, "Razer Blade Stealth 13 Late 2019"),
125 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
130 static int acpi_button_add(struct acpi_device *device);
131 static int acpi_button_remove(struct acpi_device *device);
132 static void acpi_button_notify(struct acpi_device *device, u32 event);
134 #ifdef CONFIG_PM_SLEEP
135 static int acpi_button_suspend(struct device *dev);
136 static int acpi_button_resume(struct device *dev);
138 #define acpi_button_suspend NULL
139 #define acpi_button_resume NULL
141 static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
143 static struct acpi_driver acpi_button_driver = {
145 .class = ACPI_BUTTON_CLASS,
146 .ids = button_device_ids,
148 .add = acpi_button_add,
149 .remove = acpi_button_remove,
150 .notify = acpi_button_notify,
152 .drv.pm = &acpi_button_pm,
157 struct input_dev *input;
158 char phys[32]; /* for input device */
159 unsigned long pushed;
163 bool lid_state_initialized;
166 static struct acpi_device *lid_device;
167 static long lid_init_state = -1;
169 static unsigned long lid_report_interval __read_mostly = 500;
170 module_param(lid_report_interval, ulong, 0644);
171 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
173 /* --------------------------------------------------------------------------
175 -------------------------------------------------------------------------- */
177 static struct proc_dir_entry *acpi_button_dir;
178 static struct proc_dir_entry *acpi_lid_dir;
180 static int acpi_lid_evaluate_state(struct acpi_device *device)
182 unsigned long long lid_state;
185 status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
186 if (ACPI_FAILURE(status))
189 return lid_state ? 1 : 0;
192 static int acpi_lid_notify_state(struct acpi_device *device, int state)
194 struct acpi_button *button = acpi_driver_data(device);
199 * In lid_init_state=ignore mode, if user opens/closes lid
200 * frequently with "open" missing, and "last_time" is also updated
201 * frequently, "close" cannot be delivered to the userspace.
202 * So "last_time" is only updated after a timeout or an actual
205 if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
206 button->last_state != !!state)
211 next_report = ktime_add(button->last_time,
212 ms_to_ktime(lid_report_interval));
213 if (button->last_state == !!state &&
214 ktime_after(ktime_get(), next_report)) {
215 /* Complain the buggy firmware */
216 pr_warn_once("The lid device is not compliant to SW_LID.\n");
219 * Send the unreliable complement switch event:
221 * On most platforms, the lid device is reliable. However
222 * there are exceptions:
223 * 1. Platforms returning initial lid state as "close" by
224 * default after booting/resuming:
225 * https://bugzilla.kernel.org/show_bug.cgi?id=89211
226 * https://bugzilla.kernel.org/show_bug.cgi?id=106151
227 * 2. Platforms never reporting "open" events:
228 * https://bugzilla.kernel.org/show_bug.cgi?id=106941
229 * On these buggy platforms, the usage model of the ACPI
230 * lid device actually is:
231 * 1. The initial returning value of _LID may not be
233 * 2. The open event may not be reliable.
234 * 3. The close event is reliable.
236 * But SW_LID is typed as input switch event, the input
237 * layer checks if the event is redundant. Hence if the
238 * state is not switched, the userspace cannot see this
239 * platform triggered reliable event. By inserting a
240 * complement switch event, it then is guaranteed that the
241 * platform triggered reliable one can always be seen by
244 if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
247 * Do generate complement switch event for "close"
248 * as "close" is reliable and wrong "open" won't
249 * trigger unexpected behaviors.
250 * Do not generate complement switch event for
251 * "open" as "open" is not reliable and wrong
252 * "close" will trigger unexpected behaviors.
255 input_report_switch(button->input,
257 input_sync(button->input);
261 /* Send the platform triggered reliable event */
263 acpi_handle_debug(device->handle, "ACPI LID %s\n",
264 state ? "open" : "closed");
265 input_report_switch(button->input, SW_LID, !state);
266 input_sync(button->input);
267 button->last_state = !!state;
268 button->last_time = ktime_get();
274 static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq,
277 struct acpi_device *device = seq->private;
280 state = acpi_lid_evaluate_state(device);
281 seq_printf(seq, "state: %s\n",
282 state < 0 ? "unsupported" : (state ? "open" : "closed"));
286 static int acpi_button_add_fs(struct acpi_device *device)
288 struct acpi_button *button = acpi_driver_data(device);
289 struct proc_dir_entry *entry = NULL;
292 /* procfs I/F for ACPI lid device only */
293 if (button->type != ACPI_BUTTON_TYPE_LID)
296 if (acpi_button_dir || acpi_lid_dir) {
297 printk(KERN_ERR PREFIX "More than one Lid device found!\n");
301 /* create /proc/acpi/button */
302 acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
303 if (!acpi_button_dir)
306 /* create /proc/acpi/button/lid */
307 acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
310 goto remove_button_dir;
313 /* create /proc/acpi/button/lid/LID/ */
314 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
315 if (!acpi_device_dir(device)) {
320 /* create /proc/acpi/button/lid/LID/state */
321 entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO,
322 acpi_device_dir(device), acpi_button_state_seq_show,
333 remove_proc_entry(acpi_device_bid(device),
335 acpi_device_dir(device) = NULL;
337 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
340 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
341 acpi_button_dir = NULL;
345 static int acpi_button_remove_fs(struct acpi_device *device)
347 struct acpi_button *button = acpi_driver_data(device);
349 if (button->type != ACPI_BUTTON_TYPE_LID)
352 remove_proc_entry(ACPI_BUTTON_FILE_STATE,
353 acpi_device_dir(device));
354 remove_proc_entry(acpi_device_bid(device),
356 acpi_device_dir(device) = NULL;
357 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
359 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
360 acpi_button_dir = NULL;
365 /* --------------------------------------------------------------------------
367 -------------------------------------------------------------------------- */
368 int acpi_lid_open(void)
373 return acpi_lid_evaluate_state(lid_device);
375 EXPORT_SYMBOL(acpi_lid_open);
377 static int acpi_lid_update_state(struct acpi_device *device,
382 state = acpi_lid_evaluate_state(device);
386 if (state && signal_wakeup)
387 acpi_pm_wakeup_event(&device->dev);
389 return acpi_lid_notify_state(device, state);
392 static void acpi_lid_initialize_state(struct acpi_device *device)
394 struct acpi_button *button = acpi_driver_data(device);
396 switch (lid_init_state) {
397 case ACPI_BUTTON_LID_INIT_OPEN:
398 (void)acpi_lid_notify_state(device, 1);
400 case ACPI_BUTTON_LID_INIT_METHOD:
401 (void)acpi_lid_update_state(device, false);
403 case ACPI_BUTTON_LID_INIT_IGNORE:
408 button->lid_state_initialized = true;
411 static void acpi_button_notify(struct acpi_device *device, u32 event)
413 struct acpi_button *button = acpi_driver_data(device);
414 struct input_dev *input;
417 case ACPI_FIXED_HARDWARE_EVENT:
418 event = ACPI_BUTTON_NOTIFY_STATUS;
420 case ACPI_BUTTON_NOTIFY_STATUS:
421 input = button->input;
422 if (button->type == ACPI_BUTTON_TYPE_LID) {
423 if (button->lid_state_initialized)
424 acpi_lid_update_state(device, true);
428 acpi_pm_wakeup_event(&device->dev);
429 if (button->suspended)
432 keycode = test_bit(KEY_SLEEP, input->keybit) ?
433 KEY_SLEEP : KEY_POWER;
434 input_report_key(input, keycode, 1);
436 input_report_key(input, keycode, 0);
439 acpi_bus_generate_netlink_event(
440 device->pnp.device_class,
441 dev_name(&device->dev),
442 event, ++button->pushed);
446 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
447 "Unsupported event [0x%x]\n", event));
452 #ifdef CONFIG_PM_SLEEP
453 static int acpi_button_suspend(struct device *dev)
455 struct acpi_device *device = to_acpi_device(dev);
456 struct acpi_button *button = acpi_driver_data(device);
458 button->suspended = true;
462 static int acpi_button_resume(struct device *dev)
464 struct acpi_device *device = to_acpi_device(dev);
465 struct acpi_button *button = acpi_driver_data(device);
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);
477 static int acpi_lid_input_open(struct input_dev *input)
479 struct acpi_device *device = input_get_drvdata(input);
480 struct acpi_button *button = acpi_driver_data(device);
482 button->last_state = !!acpi_lid_evaluate_state(device);
483 button->last_time = ktime_get();
484 acpi_lid_initialize_state(device);
489 static int acpi_button_add(struct acpi_device *device)
491 struct acpi_button *button;
492 struct input_dev *input;
493 const char *hid = acpi_device_hid(device);
497 if (!strcmp(hid, ACPI_BUTTON_HID_LID) &&
498 lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED)
501 button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
505 device->driver_data = button;
507 button->input = input = input_allocate_device();
510 goto err_free_button;
513 name = acpi_device_name(device);
514 class = acpi_device_class(device);
516 if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
517 !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
518 button->type = ACPI_BUTTON_TYPE_POWER;
519 strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
520 sprintf(class, "%s/%s",
521 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
522 } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
523 !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
524 button->type = ACPI_BUTTON_TYPE_SLEEP;
525 strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
526 sprintf(class, "%s/%s",
527 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
528 } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
529 button->type = ACPI_BUTTON_TYPE_LID;
530 strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
531 sprintf(class, "%s/%s",
532 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
533 input->open = acpi_lid_input_open;
535 printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
540 error = acpi_button_add_fs(device);
544 snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
547 input->phys = button->phys;
548 input->id.bustype = BUS_HOST;
549 input->id.product = button->type;
550 input->dev.parent = &device->dev;
552 switch (button->type) {
553 case ACPI_BUTTON_TYPE_POWER:
554 input_set_capability(input, EV_KEY, KEY_POWER);
557 case ACPI_BUTTON_TYPE_SLEEP:
558 input_set_capability(input, EV_KEY, KEY_SLEEP);
561 case ACPI_BUTTON_TYPE_LID:
562 input_set_capability(input, EV_SW, SW_LID);
566 input_set_drvdata(input, device);
567 error = input_register_device(input);
570 if (button->type == ACPI_BUTTON_TYPE_LID) {
572 * This assumes there's only one lid device, or if there are
573 * more we only care about the last one...
578 device_init_wakeup(&device->dev, true);
579 printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
583 acpi_button_remove_fs(device);
585 input_free_device(input);
591 static int acpi_button_remove(struct acpi_device *device)
593 struct acpi_button *button = acpi_driver_data(device);
595 acpi_button_remove_fs(device);
596 input_unregister_device(button->input);
601 static int param_set_lid_init_state(const char *val,
602 const struct kernel_param *kp)
606 i = sysfs_match_string(lid_init_state_str, val);
611 pr_info("Initial lid state set to '%s'\n", lid_init_state_str[i]);
615 static int param_get_lid_init_state(char *buf, const struct kernel_param *kp)
619 for (i = 0; i < ARRAY_SIZE(lid_init_state_str); i++)
620 if (i == lid_init_state)
621 c += sprintf(buf + c, "[%s] ", lid_init_state_str[i]);
623 c += sprintf(buf + c, "%s ", lid_init_state_str[i]);
625 buf[c - 1] = '\n'; /* Replace the final space with a newline */
630 module_param_call(lid_init_state,
631 param_set_lid_init_state, param_get_lid_init_state,
633 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
635 static int acpi_button_register_driver(struct acpi_driver *driver)
637 const struct dmi_system_id *dmi_id;
639 if (lid_init_state == -1) {
640 dmi_id = dmi_first_match(dmi_lid_quirks);
642 lid_init_state = (long)dmi_id->driver_data;
644 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
648 * Modules such as nouveau.ko and i915.ko have a link time dependency
649 * on acpi_lid_open(), and would therefore not be loadable on ACPI
650 * capable kernels booted in non-ACPI mode if the return value of
651 * acpi_bus_register_driver() is returned from here with ACPI disabled
652 * when this driver is built as a module.
657 return acpi_bus_register_driver(driver);
660 static void acpi_button_unregister_driver(struct acpi_driver *driver)
663 acpi_bus_unregister_driver(driver);
666 module_driver(acpi_button_driver, acpi_button_register_driver,
667 acpi_button_unregister_driver);