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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);
v4.10.11
 
  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);