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 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
29 #define ACPI_BUTTON_SUBCLASS_POWER "power"
30 #define ACPI_BUTTON_DEVICE_NAME_POWER "Power Button"
31 #define ACPI_BUTTON_TYPE_POWER 0x01
33 #define ACPI_BUTTON_SUBCLASS_SLEEP "sleep"
34 #define ACPI_BUTTON_DEVICE_NAME_SLEEP "Sleep Button"
35 #define ACPI_BUTTON_TYPE_SLEEP 0x03
37 #define ACPI_BUTTON_SUBCLASS_LID "lid"
38 #define ACPI_BUTTON_DEVICE_NAME_LID "Lid Switch"
39 #define ACPI_BUTTON_TYPE_LID 0x05
42 ACPI_BUTTON_LID_INIT_IGNORE,
43 ACPI_BUTTON_LID_INIT_OPEN,
44 ACPI_BUTTON_LID_INIT_METHOD,
45 ACPI_BUTTON_LID_INIT_DISABLED,
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",
55 MODULE_AUTHOR("Paul Diefenbaugh");
56 MODULE_DESCRIPTION("ACPI Button Driver");
57 MODULE_LICENSE("GPL");
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},
67 MODULE_DEVICE_TABLE(acpi, button_device_ids);
69 /* Please keep this list sorted alphabetically by vendor and model */
70 static const struct dmi_system_id dmi_lid_quirks[] = {
72 /* GP-electronic T701, _LID method points to a floating GPIO */
74 DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
75 DMI_MATCH(DMI_PRODUCT_NAME, "T701"),
76 DMI_MATCH(DMI_BIOS_VERSION, "BYT70A.YNCHENG.WIN.007"),
78 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
82 * Medion Akoya E2215T, notification of the LID device only
83 * happens on close, not on open and _LID always returns closed.
86 DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
87 DMI_MATCH(DMI_PRODUCT_NAME, "E2215T"),
89 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
93 * Medion Akoya E2228T, notification of the LID device only
94 * happens on close, not on open and _LID always returns closed.
97 DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
98 DMI_MATCH(DMI_PRODUCT_NAME, "E2228T"),
100 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
104 * Razer Blade Stealth 13 late 2019, notification of the LID device
105 * only happens on close, not on open and _LID always returns closed.
108 DMI_MATCH(DMI_SYS_VENDOR, "Razer"),
109 DMI_MATCH(DMI_PRODUCT_NAME, "Razer Blade Stealth 13 Late 2019"),
111 .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
116 static int acpi_button_add(struct acpi_device *device);
117 static int acpi_button_remove(struct acpi_device *device);
118 static void acpi_button_notify(struct acpi_device *device, u32 event);
120 #ifdef CONFIG_PM_SLEEP
121 static int acpi_button_suspend(struct device *dev);
122 static int acpi_button_resume(struct device *dev);
124 #define acpi_button_suspend NULL
125 #define acpi_button_resume NULL
127 static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
129 static struct acpi_driver acpi_button_driver = {
131 .class = ACPI_BUTTON_CLASS,
132 .ids = button_device_ids,
134 .add = acpi_button_add,
135 .remove = acpi_button_remove,
136 .notify = acpi_button_notify,
138 .drv.pm = &acpi_button_pm,
143 struct input_dev *input;
144 char phys[32]; /* for input device */
145 unsigned long pushed;
149 bool lid_state_initialized;
152 static struct acpi_device *lid_device;
153 static long lid_init_state = -1;
155 static unsigned long lid_report_interval __read_mostly = 500;
156 module_param(lid_report_interval, ulong, 0644);
157 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
159 /* --------------------------------------------------------------------------
161 -------------------------------------------------------------------------- */
163 static struct proc_dir_entry *acpi_button_dir;
164 static struct proc_dir_entry *acpi_lid_dir;
166 static int acpi_lid_evaluate_state(struct acpi_device *device)
168 unsigned long long lid_state;
171 status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
172 if (ACPI_FAILURE(status))
175 return lid_state ? 1 : 0;
178 static int acpi_lid_notify_state(struct acpi_device *device, int state)
180 struct acpi_button *button = acpi_driver_data(device);
185 * In lid_init_state=ignore mode, if user opens/closes lid
186 * frequently with "open" missing, and "last_time" is also updated
187 * frequently, "close" cannot be delivered to the userspace.
188 * So "last_time" is only updated after a timeout or an actual
191 if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
192 button->last_state != !!state)
197 next_report = ktime_add(button->last_time,
198 ms_to_ktime(lid_report_interval));
199 if (button->last_state == !!state &&
200 ktime_after(ktime_get(), next_report)) {
201 /* Complain the buggy firmware */
202 pr_warn_once("The lid device is not compliant to SW_LID.\n");
205 * Send the unreliable complement switch event:
207 * On most platforms, the lid device is reliable. However
208 * there are exceptions:
209 * 1. Platforms returning initial lid state as "close" by
210 * default after booting/resuming:
211 * https://bugzilla.kernel.org/show_bug.cgi?id=89211
212 * https://bugzilla.kernel.org/show_bug.cgi?id=106151
213 * 2. Platforms never reporting "open" events:
214 * https://bugzilla.kernel.org/show_bug.cgi?id=106941
215 * On these buggy platforms, the usage model of the ACPI
216 * lid device actually is:
217 * 1. The initial returning value of _LID may not be
219 * 2. The open event may not be reliable.
220 * 3. The close event is reliable.
222 * But SW_LID is typed as input switch event, the input
223 * layer checks if the event is redundant. Hence if the
224 * state is not switched, the userspace cannot see this
225 * platform triggered reliable event. By inserting a
226 * complement switch event, it then is guaranteed that the
227 * platform triggered reliable one can always be seen by
230 if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
233 * Do generate complement switch event for "close"
234 * as "close" is reliable and wrong "open" won't
235 * trigger unexpected behaviors.
236 * Do not generate complement switch event for
237 * "open" as "open" is not reliable and wrong
238 * "close" will trigger unexpected behaviors.
241 input_report_switch(button->input,
243 input_sync(button->input);
247 /* Send the platform triggered reliable event */
249 acpi_handle_debug(device->handle, "ACPI LID %s\n",
250 state ? "open" : "closed");
251 input_report_switch(button->input, SW_LID, !state);
252 input_sync(button->input);
253 button->last_state = !!state;
254 button->last_time = ktime_get();
260 static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq,
263 struct acpi_device *device = seq->private;
266 state = acpi_lid_evaluate_state(device);
267 seq_printf(seq, "state: %s\n",
268 state < 0 ? "unsupported" : (state ? "open" : "closed"));
272 static int acpi_button_add_fs(struct acpi_device *device)
274 struct acpi_button *button = acpi_driver_data(device);
275 struct proc_dir_entry *entry = NULL;
278 /* procfs I/F for ACPI lid device only */
279 if (button->type != ACPI_BUTTON_TYPE_LID)
282 if (acpi_button_dir || acpi_lid_dir) {
283 pr_info("More than one Lid device found!\n");
287 /* create /proc/acpi/button */
288 acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
289 if (!acpi_button_dir)
292 /* create /proc/acpi/button/lid */
293 acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
296 goto remove_button_dir;
299 /* create /proc/acpi/button/lid/LID/ */
300 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
301 if (!acpi_device_dir(device)) {
306 /* create /proc/acpi/button/lid/LID/state */
307 entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO,
308 acpi_device_dir(device), acpi_button_state_seq_show,
319 remove_proc_entry(acpi_device_bid(device),
321 acpi_device_dir(device) = NULL;
323 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
326 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
327 acpi_button_dir = NULL;
331 static int acpi_button_remove_fs(struct acpi_device *device)
333 struct acpi_button *button = acpi_driver_data(device);
335 if (button->type != ACPI_BUTTON_TYPE_LID)
338 remove_proc_entry(ACPI_BUTTON_FILE_STATE,
339 acpi_device_dir(device));
340 remove_proc_entry(acpi_device_bid(device),
342 acpi_device_dir(device) = NULL;
343 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
345 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
346 acpi_button_dir = NULL;
351 /* --------------------------------------------------------------------------
353 -------------------------------------------------------------------------- */
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,
368 state = acpi_lid_evaluate_state(device);
372 if (state && signal_wakeup)
373 acpi_pm_wakeup_event(&device->dev);
375 return acpi_lid_notify_state(device, state);
378 static void acpi_lid_initialize_state(struct acpi_device *device)
380 struct acpi_button *button = acpi_driver_data(device);
382 switch (lid_init_state) {
383 case ACPI_BUTTON_LID_INIT_OPEN:
384 (void)acpi_lid_notify_state(device, 1);
386 case ACPI_BUTTON_LID_INIT_METHOD:
387 (void)acpi_lid_update_state(device, false);
389 case ACPI_BUTTON_LID_INIT_IGNORE:
394 button->lid_state_initialized = true;
397 static void acpi_button_notify(struct acpi_device *device, u32 event)
399 struct acpi_button *button = acpi_driver_data(device);
400 struct input_dev *input;
403 case ACPI_FIXED_HARDWARE_EVENT:
404 event = ACPI_BUTTON_NOTIFY_STATUS;
406 case ACPI_BUTTON_NOTIFY_STATUS:
407 input = button->input;
408 if (button->type == ACPI_BUTTON_TYPE_LID) {
409 if (button->lid_state_initialized)
410 acpi_lid_update_state(device, true);
414 acpi_pm_wakeup_event(&device->dev);
415 if (button->suspended)
418 keycode = test_bit(KEY_SLEEP, input->keybit) ?
419 KEY_SLEEP : KEY_POWER;
420 input_report_key(input, keycode, 1);
422 input_report_key(input, keycode, 0);
425 acpi_bus_generate_netlink_event(
426 device->pnp.device_class,
427 dev_name(&device->dev),
428 event, ++button->pushed);
432 acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
438 #ifdef CONFIG_PM_SLEEP
439 static int acpi_button_suspend(struct device *dev)
441 struct acpi_device *device = to_acpi_device(dev);
442 struct acpi_button *button = acpi_driver_data(device);
444 button->suspended = true;
448 static int acpi_button_resume(struct device *dev)
450 struct acpi_device *device = to_acpi_device(dev);
451 struct acpi_button *button = acpi_driver_data(device);
453 button->suspended = false;
454 if (button->type == ACPI_BUTTON_TYPE_LID) {
455 button->last_state = !!acpi_lid_evaluate_state(device);
456 button->last_time = ktime_get();
457 acpi_lid_initialize_state(device);
463 static int acpi_lid_input_open(struct input_dev *input)
465 struct acpi_device *device = input_get_drvdata(input);
466 struct acpi_button *button = acpi_driver_data(device);
468 button->last_state = !!acpi_lid_evaluate_state(device);
469 button->last_time = ktime_get();
470 acpi_lid_initialize_state(device);
475 static int acpi_button_add(struct acpi_device *device)
477 struct acpi_button *button;
478 struct input_dev *input;
479 const char *hid = acpi_device_hid(device);
483 if (!strcmp(hid, ACPI_BUTTON_HID_LID) &&
484 lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED)
487 button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
491 device->driver_data = button;
493 button->input = input = input_allocate_device();
496 goto err_free_button;
499 name = acpi_device_name(device);
500 class = acpi_device_class(device);
502 if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
503 !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
504 button->type = ACPI_BUTTON_TYPE_POWER;
505 strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
506 sprintf(class, "%s/%s",
507 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
508 } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
509 !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
510 button->type = ACPI_BUTTON_TYPE_SLEEP;
511 strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
512 sprintf(class, "%s/%s",
513 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
514 } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
515 button->type = ACPI_BUTTON_TYPE_LID;
516 strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
517 sprintf(class, "%s/%s",
518 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
519 input->open = acpi_lid_input_open;
521 pr_info("Unsupported hid [%s]\n", hid);
526 error = acpi_button_add_fs(device);
530 snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
533 input->phys = button->phys;
534 input->id.bustype = BUS_HOST;
535 input->id.product = button->type;
536 input->dev.parent = &device->dev;
538 switch (button->type) {
539 case ACPI_BUTTON_TYPE_POWER:
540 input_set_capability(input, EV_KEY, KEY_POWER);
543 case ACPI_BUTTON_TYPE_SLEEP:
544 input_set_capability(input, EV_KEY, KEY_SLEEP);
547 case ACPI_BUTTON_TYPE_LID:
548 input_set_capability(input, EV_SW, SW_LID);
552 input_set_drvdata(input, device);
553 error = input_register_device(input);
556 if (button->type == ACPI_BUTTON_TYPE_LID) {
558 * This assumes there's only one lid device, or if there are
559 * more we only care about the last one...
564 device_init_wakeup(&device->dev, true);
565 pr_info("%s [%s]\n", name, acpi_device_bid(device));
569 acpi_button_remove_fs(device);
571 input_free_device(input);
577 static int acpi_button_remove(struct acpi_device *device)
579 struct acpi_button *button = acpi_driver_data(device);
581 acpi_button_remove_fs(device);
582 input_unregister_device(button->input);
587 static int param_set_lid_init_state(const char *val,
588 const struct kernel_param *kp)
592 i = sysfs_match_string(lid_init_state_str, val);
597 pr_info("Initial lid state set to '%s'\n", lid_init_state_str[i]);
601 static int param_get_lid_init_state(char *buf, const struct kernel_param *kp)
605 for (i = 0; i < ARRAY_SIZE(lid_init_state_str); i++)
606 if (i == lid_init_state)
607 c += sprintf(buf + c, "[%s] ", lid_init_state_str[i]);
609 c += sprintf(buf + c, "%s ", lid_init_state_str[i]);
611 buf[c - 1] = '\n'; /* Replace the final space with a newline */
616 module_param_call(lid_init_state,
617 param_set_lid_init_state, param_get_lid_init_state,
619 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
621 static int acpi_button_register_driver(struct acpi_driver *driver)
623 const struct dmi_system_id *dmi_id;
625 if (lid_init_state == -1) {
626 dmi_id = dmi_first_match(dmi_lid_quirks);
628 lid_init_state = (long)dmi_id->driver_data;
630 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
634 * Modules such as nouveau.ko and i915.ko have a link time dependency
635 * on acpi_lid_open(), and would therefore not be loadable on ACPI
636 * capable kernels booted in non-ACPI mode if the return value of
637 * acpi_bus_register_driver() is returned from here with ACPI disabled
638 * when this driver is built as a module.
643 return acpi_bus_register_driver(driver);
646 static void acpi_button_unregister_driver(struct acpi_driver *driver)
649 acpi_bus_unregister_driver(driver);
652 module_driver(acpi_button_driver, acpi_button_register_driver,
653 acpi_button_unregister_driver);