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v5.4
  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
 52ACPI_MODULE_NAME("button");
 53
 54MODULE_AUTHOR("Paul Diefenbaugh");
 55MODULE_DESCRIPTION("ACPI Button Driver");
 56MODULE_LICENSE("GPL");
 57
 58static 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};
 66MODULE_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 */
 72static 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
 84static int acpi_button_add(struct acpi_device *device);
 85static int acpi_button_remove(struct acpi_device *device);
 86static void acpi_button_notify(struct acpi_device *device, u32 event);
 87
 88#ifdef CONFIG_PM_SLEEP
 89static int acpi_button_suspend(struct device *dev);
 90static int acpi_button_resume(struct device *dev);
 91#else
 92#define acpi_button_suspend NULL
 93#define acpi_button_resume NULL
 94#endif
 95static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
 96
 97static 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
109struct 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
119static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
120static struct acpi_device *lid_device;
121static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
122
123static unsigned long lid_report_interval __read_mostly = 500;
124module_param(lid_report_interval, ulong, 0644);
125MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
126
127/* --------------------------------------------------------------------------
128                              FS Interface (/proc)
129   -------------------------------------------------------------------------- */
130
131static struct proc_dir_entry *acpi_button_dir;
132static struct proc_dir_entry *acpi_lid_dir;
133
134static 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
146static 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
240static 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
 
 
 
 
 
 
 
 
 
 
 
 
 
252static 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
295done:
296	return ret;
297
298remove_dev_dir:
299	remove_proc_entry(acpi_device_bid(device),
300			  acpi_lid_dir);
301	acpi_device_dir(device) = NULL;
302remove_lid_dir:
303	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
304	acpi_lid_dir = NULL;
305remove_button_dir:
306	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
307	acpi_button_dir = NULL;
308	goto done;
309}
310
311static 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   -------------------------------------------------------------------------- */
334int acpi_lid_notifier_register(struct notifier_block *nb)
335{
336	return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
337}
338EXPORT_SYMBOL(acpi_lid_notifier_register);
339
340int acpi_lid_notifier_unregister(struct notifier_block *nb)
341{
342	return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
343}
344EXPORT_SYMBOL(acpi_lid_notifier_unregister);
345
346int acpi_lid_open(void)
347{
348	if (!lid_device)
349		return -ENODEV;
350
351	return acpi_lid_evaluate_state(lid_device);
352}
353EXPORT_SYMBOL(acpi_lid_open);
354
355static 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
370static 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
385static 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
431static 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
440static 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
455static 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
467static 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
568static 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
578static 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
597static 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
613module_param_call(lid_init_state,
614		  param_set_lid_init_state, param_get_lid_init_state,
615		  NULL, 0644);
616MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
617
618static 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
633static void acpi_button_unregister_driver(struct acpi_driver *driver)
634{
635	if (!acpi_disabled)
636		acpi_bus_unregister_driver(driver);
637}
638
639module_driver(acpi_button_driver, acpi_button_register_driver,
640	       acpi_button_unregister_driver);
v4.17
 
  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 <linux/dmi.h>
 34#include <acpi/button.h>
 35
 36#define PREFIX "ACPI: "
 37
 38#define ACPI_BUTTON_CLASS		"button"
 39#define ACPI_BUTTON_FILE_INFO		"info"
 40#define ACPI_BUTTON_FILE_STATE		"state"
 41#define ACPI_BUTTON_TYPE_UNKNOWN	0x00
 42#define ACPI_BUTTON_NOTIFY_STATUS	0x80
 43
 44#define ACPI_BUTTON_SUBCLASS_POWER	"power"
 45#define ACPI_BUTTON_HID_POWER		"PNP0C0C"
 46#define ACPI_BUTTON_DEVICE_NAME_POWER	"Power Button"
 47#define ACPI_BUTTON_TYPE_POWER		0x01
 48
 49#define ACPI_BUTTON_SUBCLASS_SLEEP	"sleep"
 50#define ACPI_BUTTON_HID_SLEEP		"PNP0C0E"
 51#define ACPI_BUTTON_DEVICE_NAME_SLEEP	"Sleep Button"
 52#define ACPI_BUTTON_TYPE_SLEEP		0x03
 53
 54#define ACPI_BUTTON_SUBCLASS_LID	"lid"
 55#define ACPI_BUTTON_HID_LID		"PNP0C0D"
 56#define ACPI_BUTTON_DEVICE_NAME_LID	"Lid Switch"
 57#define ACPI_BUTTON_TYPE_LID		0x05
 58
 59#define ACPI_BUTTON_LID_INIT_IGNORE	0x00
 60#define ACPI_BUTTON_LID_INIT_OPEN	0x01
 61#define ACPI_BUTTON_LID_INIT_METHOD	0x02
 62
 63#define _COMPONENT		ACPI_BUTTON_COMPONENT
 64ACPI_MODULE_NAME("button");
 65
 66MODULE_AUTHOR("Paul Diefenbaugh");
 67MODULE_DESCRIPTION("ACPI Button Driver");
 68MODULE_LICENSE("GPL");
 69
 70static const struct acpi_device_id button_device_ids[] = {
 71	{ACPI_BUTTON_HID_LID,    0},
 72	{ACPI_BUTTON_HID_SLEEP,  0},
 73	{ACPI_BUTTON_HID_SLEEPF, 0},
 74	{ACPI_BUTTON_HID_POWER,  0},
 75	{ACPI_BUTTON_HID_POWERF, 0},
 76	{"", 0},
 77};
 78MODULE_DEVICE_TABLE(acpi, button_device_ids);
 79
 80/*
 81 * Some devices which don't even have a lid in anyway have a broken _LID
 82 * method (e.g. pointing to a floating gpio pin) causing spurious LID events.
 83 */
 84static const struct dmi_system_id lid_blacklst[] = {
 85	{
 86		/* GP-electronic T701 */
 87		.matches = {
 88			DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
 89			DMI_MATCH(DMI_PRODUCT_NAME, "T701"),
 90			DMI_MATCH(DMI_BIOS_VERSION, "BYT70A.YNCHENG.WIN.007"),
 91		},
 92	},
 93	{}
 94};
 95
 96static int acpi_button_add(struct acpi_device *device);
 97static int acpi_button_remove(struct acpi_device *device);
 98static void acpi_button_notify(struct acpi_device *device, u32 event);
 99
100#ifdef CONFIG_PM_SLEEP
101static int acpi_button_suspend(struct device *dev);
102static int acpi_button_resume(struct device *dev);
103#else
104#define acpi_button_suspend NULL
105#define acpi_button_resume NULL
106#endif
107static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
108
109static struct acpi_driver acpi_button_driver = {
110	.name = "button",
111	.class = ACPI_BUTTON_CLASS,
112	.ids = button_device_ids,
113	.ops = {
114		.add = acpi_button_add,
115		.remove = acpi_button_remove,
116		.notify = acpi_button_notify,
117	},
118	.drv.pm = &acpi_button_pm,
119};
120
121struct acpi_button {
122	unsigned int type;
123	struct input_dev *input;
124	char phys[32];			/* for input device */
125	unsigned long pushed;
126	int last_state;
127	ktime_t last_time;
128	bool suspended;
129};
130
131static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
132static struct acpi_device *lid_device;
133static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
134
135static unsigned long lid_report_interval __read_mostly = 500;
136module_param(lid_report_interval, ulong, 0644);
137MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
138
139/* --------------------------------------------------------------------------
140                              FS Interface (/proc)
141   -------------------------------------------------------------------------- */
142
143static struct proc_dir_entry *acpi_button_dir;
144static struct proc_dir_entry *acpi_lid_dir;
145
146static int acpi_lid_evaluate_state(struct acpi_device *device)
147{
148	unsigned long long lid_state;
149	acpi_status status;
150
151	status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
152	if (ACPI_FAILURE(status))
153		return -ENODEV;
154
155	return lid_state ? 1 : 0;
156}
157
158static int acpi_lid_notify_state(struct acpi_device *device, int state)
159{
160	struct acpi_button *button = acpi_driver_data(device);
161	int ret;
162	ktime_t next_report;
163	bool do_update;
164
165	/*
166	 * In lid_init_state=ignore mode, if user opens/closes lid
167	 * frequently with "open" missing, and "last_time" is also updated
168	 * frequently, "close" cannot be delivered to the userspace.
169	 * So "last_time" is only updated after a timeout or an actual
170	 * switch.
171	 */
172	if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
173	    button->last_state != !!state)
174		do_update = true;
175	else
176		do_update = false;
177
178	next_report = ktime_add(button->last_time,
179				ms_to_ktime(lid_report_interval));
180	if (button->last_state == !!state &&
181	    ktime_after(ktime_get(), next_report)) {
182		/* Complain the buggy firmware */
183		pr_warn_once("The lid device is not compliant to SW_LID.\n");
184
185		/*
186		 * Send the unreliable complement switch event:
187		 *
188		 * On most platforms, the lid device is reliable. However
189		 * there are exceptions:
190		 * 1. Platforms returning initial lid state as "close" by
191		 *    default after booting/resuming:
192		 *     https://bugzilla.kernel.org/show_bug.cgi?id=89211
193		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106151
194		 * 2. Platforms never reporting "open" events:
195		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106941
196		 * On these buggy platforms, the usage model of the ACPI
197		 * lid device actually is:
198		 * 1. The initial returning value of _LID may not be
199		 *    reliable.
200		 * 2. The open event may not be reliable.
201		 * 3. The close event is reliable.
202		 *
203		 * But SW_LID is typed as input switch event, the input
204		 * layer checks if the event is redundant. Hence if the
205		 * state is not switched, the userspace cannot see this
206		 * platform triggered reliable event. By inserting a
207		 * complement switch event, it then is guaranteed that the
208		 * platform triggered reliable one can always be seen by
209		 * the userspace.
210		 */
211		if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
212			do_update = true;
213			/*
214			 * Do generate complement switch event for "close"
215			 * as "close" is reliable and wrong "open" won't
216			 * trigger unexpected behaviors.
217			 * Do not generate complement switch event for
218			 * "open" as "open" is not reliable and wrong
219			 * "close" will trigger unexpected behaviors.
220			 */
221			if (!state) {
222				input_report_switch(button->input,
223						    SW_LID, state);
224				input_sync(button->input);
225			}
226		}
227	}
228	/* Send the platform triggered reliable event */
229	if (do_update) {
230		acpi_handle_debug(device->handle, "ACPI LID %s\n",
231				  state ? "open" : "closed");
232		input_report_switch(button->input, SW_LID, !state);
233		input_sync(button->input);
234		button->last_state = !!state;
235		button->last_time = ktime_get();
236	}
237
238	if (state)
239		acpi_pm_wakeup_event(&device->dev);
240
241	ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
242	if (ret == NOTIFY_DONE)
243		ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
244						   device);
245	if (ret == NOTIFY_DONE || ret == NOTIFY_OK) {
246		/*
247		 * It is also regarded as success if the notifier_chain
248		 * returns NOTIFY_OK or NOTIFY_DONE.
249		 */
250		ret = 0;
251	}
252	return ret;
253}
254
255static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
 
256{
257	struct acpi_device *device = seq->private;
258	int state;
259
260	state = acpi_lid_evaluate_state(device);
261	seq_printf(seq, "state:      %s\n",
262		   state < 0 ? "unsupported" : (state ? "open" : "closed"));
263	return 0;
264}
265
266static int acpi_button_state_open_fs(struct inode *inode, struct file *file)
267{
268	return single_open(file, acpi_button_state_seq_show, PDE_DATA(inode));
269}
270
271static const struct file_operations acpi_button_state_fops = {
272	.owner = THIS_MODULE,
273	.open = acpi_button_state_open_fs,
274	.read = seq_read,
275	.llseek = seq_lseek,
276	.release = single_release,
277};
278
279static int acpi_button_add_fs(struct acpi_device *device)
280{
281	struct acpi_button *button = acpi_driver_data(device);
282	struct proc_dir_entry *entry = NULL;
283	int ret = 0;
284
285	/* procfs I/F for ACPI lid device only */
286	if (button->type != ACPI_BUTTON_TYPE_LID)
287		return 0;
288
289	if (acpi_button_dir || acpi_lid_dir) {
290		printk(KERN_ERR PREFIX "More than one Lid device found!\n");
291		return -EEXIST;
292	}
293
294	/* create /proc/acpi/button */
295	acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
296	if (!acpi_button_dir)
297		return -ENODEV;
298
299	/* create /proc/acpi/button/lid */
300	acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
301	if (!acpi_lid_dir) {
302		ret = -ENODEV;
303		goto remove_button_dir;
304	}
305
306	/* create /proc/acpi/button/lid/LID/ */
307	acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
308	if (!acpi_device_dir(device)) {
309		ret = -ENODEV;
310		goto remove_lid_dir;
311	}
312
313	/* create /proc/acpi/button/lid/LID/state */
314	entry = proc_create_data(ACPI_BUTTON_FILE_STATE,
315				 S_IRUGO, acpi_device_dir(device),
316				 &acpi_button_state_fops, device);
317	if (!entry) {
318		ret = -ENODEV;
319		goto remove_dev_dir;
320	}
321
322done:
323	return ret;
324
325remove_dev_dir:
326	remove_proc_entry(acpi_device_bid(device),
327			  acpi_lid_dir);
328	acpi_device_dir(device) = NULL;
329remove_lid_dir:
330	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
331	acpi_lid_dir = NULL;
332remove_button_dir:
333	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
334	acpi_button_dir = NULL;
335	goto done;
336}
337
338static int acpi_button_remove_fs(struct acpi_device *device)
339{
340	struct acpi_button *button = acpi_driver_data(device);
341
342	if (button->type != ACPI_BUTTON_TYPE_LID)
343		return 0;
344
345	remove_proc_entry(ACPI_BUTTON_FILE_STATE,
346			  acpi_device_dir(device));
347	remove_proc_entry(acpi_device_bid(device),
348			  acpi_lid_dir);
349	acpi_device_dir(device) = NULL;
350	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
351	acpi_lid_dir = NULL;
352	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
353	acpi_button_dir = NULL;
354
355	return 0;
356}
357
358/* --------------------------------------------------------------------------
359                                Driver Interface
360   -------------------------------------------------------------------------- */
361int acpi_lid_notifier_register(struct notifier_block *nb)
362{
363	return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
364}
365EXPORT_SYMBOL(acpi_lid_notifier_register);
366
367int acpi_lid_notifier_unregister(struct notifier_block *nb)
368{
369	return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
370}
371EXPORT_SYMBOL(acpi_lid_notifier_unregister);
372
373int acpi_lid_open(void)
374{
375	if (!lid_device)
376		return -ENODEV;
377
378	return acpi_lid_evaluate_state(lid_device);
379}
380EXPORT_SYMBOL(acpi_lid_open);
381
382static int acpi_lid_update_state(struct acpi_device *device)
 
383{
384	int state;
385
386	state = acpi_lid_evaluate_state(device);
387	if (state < 0)
388		return state;
389
 
 
 
390	return acpi_lid_notify_state(device, state);
391}
392
393static void acpi_lid_initialize_state(struct acpi_device *device)
394{
395	switch (lid_init_state) {
396	case ACPI_BUTTON_LID_INIT_OPEN:
397		(void)acpi_lid_notify_state(device, 1);
398		break;
399	case ACPI_BUTTON_LID_INIT_METHOD:
400		(void)acpi_lid_update_state(device);
401		break;
402	case ACPI_BUTTON_LID_INIT_IGNORE:
403	default:
404		break;
405	}
406}
407
408static void acpi_button_notify(struct acpi_device *device, u32 event)
409{
410	struct acpi_button *button = acpi_driver_data(device);
411	struct input_dev *input;
412	int users;
413
414	switch (event) {
415	case ACPI_FIXED_HARDWARE_EVENT:
416		event = ACPI_BUTTON_NOTIFY_STATUS;
417		/* fall through */
418	case ACPI_BUTTON_NOTIFY_STATUS:
419		input = button->input;
420		if (button->type == ACPI_BUTTON_TYPE_LID) {
421			mutex_lock(&button->input->mutex);
422			users = button->input->users;
423			mutex_unlock(&button->input->mutex);
424			if (users)
425				acpi_lid_update_state(device);
426		} else {
427			int keycode;
428
429			acpi_pm_wakeup_event(&device->dev);
430			if (button->suspended)
431				break;
432
433			keycode = test_bit(KEY_SLEEP, input->keybit) ?
434						KEY_SLEEP : KEY_POWER;
435			input_report_key(input, keycode, 1);
436			input_sync(input);
437			input_report_key(input, keycode, 0);
438			input_sync(input);
439
440			acpi_bus_generate_netlink_event(
441					device->pnp.device_class,
442					dev_name(&device->dev),
443					event, ++button->pushed);
444		}
445		break;
446	default:
447		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
448				  "Unsupported event [0x%x]\n", event));
449		break;
450	}
451}
452
453#ifdef CONFIG_PM_SLEEP
454static int acpi_button_suspend(struct device *dev)
455{
456	struct acpi_device *device = to_acpi_device(dev);
457	struct acpi_button *button = acpi_driver_data(device);
458
459	button->suspended = true;
460	return 0;
461}
462
463static int acpi_button_resume(struct device *dev)
464{
465	struct acpi_device *device = to_acpi_device(dev);
466	struct acpi_button *button = acpi_driver_data(device);
467
468	button->suspended = false;
469	if (button->type == ACPI_BUTTON_TYPE_LID && button->input->users)
 
 
470		acpi_lid_initialize_state(device);
 
471	return 0;
472}
473#endif
474
475static int acpi_lid_input_open(struct input_dev *input)
476{
477	struct acpi_device *device = input_get_drvdata(input);
478	struct acpi_button *button = acpi_driver_data(device);
479
480	button->last_state = !!acpi_lid_evaluate_state(device);
481	button->last_time = ktime_get();
482	acpi_lid_initialize_state(device);
483
484	return 0;
485}
486
487static int acpi_button_add(struct acpi_device *device)
488{
489	struct acpi_button *button;
490	struct input_dev *input;
491	const char *hid = acpi_device_hid(device);
492	char *name, *class;
493	int error;
494
495	if (!strcmp(hid, ACPI_BUTTON_HID_LID) && dmi_check_system(lid_blacklst))
496		return -ENODEV;
497
498	button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
499	if (!button)
500		return -ENOMEM;
501
502	device->driver_data = button;
503
504	button->input = input = input_allocate_device();
505	if (!input) {
506		error = -ENOMEM;
507		goto err_free_button;
508	}
509
510	name = acpi_device_name(device);
511	class = acpi_device_class(device);
512
513	if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
514	    !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
515		button->type = ACPI_BUTTON_TYPE_POWER;
516		strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
517		sprintf(class, "%s/%s",
518			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
519	} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
520		   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
521		button->type = ACPI_BUTTON_TYPE_SLEEP;
522		strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
523		sprintf(class, "%s/%s",
524			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
525	} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
526		button->type = ACPI_BUTTON_TYPE_LID;
527		strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
528		sprintf(class, "%s/%s",
529			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
530		input->open = acpi_lid_input_open;
531	} else {
532		printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
533		error = -ENODEV;
534		goto err_free_input;
535	}
536
537	error = acpi_button_add_fs(device);
538	if (error)
539		goto err_free_input;
540
541	snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
542
543	input->name = name;
544	input->phys = button->phys;
545	input->id.bustype = BUS_HOST;
546	input->id.product = button->type;
547	input->dev.parent = &device->dev;
548
549	switch (button->type) {
550	case ACPI_BUTTON_TYPE_POWER:
551		input_set_capability(input, EV_KEY, KEY_POWER);
552		break;
553
554	case ACPI_BUTTON_TYPE_SLEEP:
555		input_set_capability(input, EV_KEY, KEY_SLEEP);
556		break;
557
558	case ACPI_BUTTON_TYPE_LID:
559		input_set_capability(input, EV_SW, SW_LID);
560		break;
561	}
562
563	input_set_drvdata(input, device);
564	error = input_register_device(input);
565	if (error)
566		goto err_remove_fs;
567	if (button->type == ACPI_BUTTON_TYPE_LID) {
568		/*
569		 * This assumes there's only one lid device, or if there are
570		 * more we only care about the last one...
571		 */
572		lid_device = device;
573	}
574
575	device_init_wakeup(&device->dev, true);
576	printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
577	return 0;
578
579 err_remove_fs:
580	acpi_button_remove_fs(device);
581 err_free_input:
582	input_free_device(input);
583 err_free_button:
584	kfree(button);
585	return error;
586}
587
588static int acpi_button_remove(struct acpi_device *device)
589{
590	struct acpi_button *button = acpi_driver_data(device);
591
592	acpi_button_remove_fs(device);
593	input_unregister_device(button->input);
594	kfree(button);
595	return 0;
596}
597
598static int param_set_lid_init_state(const char *val,
599				    const struct kernel_param *kp)
600{
601	int result = 0;
602
603	if (!strncmp(val, "open", sizeof("open") - 1)) {
604		lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
605		pr_info("Notify initial lid state as open\n");
606	} else if (!strncmp(val, "method", sizeof("method") - 1)) {
607		lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
608		pr_info("Notify initial lid state with _LID return value\n");
609	} else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
610		lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
611		pr_info("Do not notify initial lid state\n");
612	} else
613		result = -EINVAL;
614	return result;
615}
616
617static int param_get_lid_init_state(char *buffer,
618				    const struct kernel_param *kp)
619{
620	switch (lid_init_state) {
621	case ACPI_BUTTON_LID_INIT_OPEN:
622		return sprintf(buffer, "open");
623	case ACPI_BUTTON_LID_INIT_METHOD:
624		return sprintf(buffer, "method");
625	case ACPI_BUTTON_LID_INIT_IGNORE:
626		return sprintf(buffer, "ignore");
627	default:
628		return sprintf(buffer, "invalid");
629	}
630	return 0;
631}
632
633module_param_call(lid_init_state,
634		  param_set_lid_init_state, param_get_lid_init_state,
635		  NULL, 0644);
636MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
637
638static int acpi_button_register_driver(struct acpi_driver *driver)
639{
640	/*
641	 * Modules such as nouveau.ko and i915.ko have a link time dependency
642	 * on acpi_lid_open(), and would therefore not be loadable on ACPI
643	 * capable kernels booted in non-ACPI mode if the return value of
644	 * acpi_bus_register_driver() is returned from here with ACPI disabled
645	 * when this driver is built as a module.
646	 */
647	if (acpi_disabled)
648		return 0;
649
650	return acpi_bus_register_driver(driver);
651}
652
653static void acpi_button_unregister_driver(struct acpi_driver *driver)
654{
655	if (!acpi_disabled)
656		acpi_bus_unregister_driver(driver);
657}
658
659module_driver(acpi_button_driver, acpi_button_register_driver,
660	       acpi_button_unregister_driver);