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 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
28
29#define ACPI_BUTTON_SUBCLASS_POWER	"power"
30#define ACPI_BUTTON_DEVICE_NAME_POWER	"Power Button"
31#define ACPI_BUTTON_TYPE_POWER		0x01
32
33#define ACPI_BUTTON_SUBCLASS_SLEEP	"sleep"
34#define ACPI_BUTTON_DEVICE_NAME_SLEEP	"Sleep Button"
35#define ACPI_BUTTON_TYPE_SLEEP		0x03
36
37#define ACPI_BUTTON_SUBCLASS_LID	"lid"
38#define ACPI_BUTTON_DEVICE_NAME_LID	"Lid Switch"
39#define ACPI_BUTTON_TYPE_LID		0x05
40
41enum {
42	ACPI_BUTTON_LID_INIT_IGNORE,
43	ACPI_BUTTON_LID_INIT_OPEN,
44	ACPI_BUTTON_LID_INIT_METHOD,
45	ACPI_BUTTON_LID_INIT_DISABLED,
46};
47
48static 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",
53};
54
55MODULE_AUTHOR("Paul Diefenbaugh");
56MODULE_DESCRIPTION("ACPI Button Driver");
57MODULE_LICENSE("GPL");
58
59static 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},
65	{"", 0},
66};
67MODULE_DEVICE_TABLE(acpi, button_device_ids);
68
69/* Please keep this list sorted alphabetically by vendor and model */
70static const struct dmi_system_id dmi_lid_quirks[] = {
71	{
72		/* GP-electronic T701, _LID method points to a floating GPIO */
73		.matches = {
74			DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
75			DMI_MATCH(DMI_PRODUCT_NAME, "T701"),
76			DMI_MATCH(DMI_BIOS_VERSION, "BYT70A.YNCHENG.WIN.007"),
77		},
78		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
79	},
80	{
81		/* Nextbook Ares 8A tablet, _LID device always reports lid closed */
82		.matches = {
83			DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
84			DMI_MATCH(DMI_PRODUCT_NAME, "CherryTrail"),
85			DMI_MATCH(DMI_BIOS_VERSION, "M882"),
86		},
87		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
88	},
89	{
90		/*
91		 * Lenovo Yoga 9 14ITL5, initial notification of the LID device
92		 * never happens.
93		 */
94		.matches = {
95			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
96			DMI_MATCH(DMI_PRODUCT_NAME, "82BG"),
97		},
98		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
99	},
100	{
101		/*
102		 * Medion Akoya E2215T, notification of the LID device only
103		 * happens on close, not on open and _LID always returns closed.
104		 */
105		.matches = {
106			DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
107			DMI_MATCH(DMI_PRODUCT_NAME, "E2215T"),
108		},
109		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
110	},
111	{
112		/*
113		 * Medion Akoya E2228T, notification of the LID device only
114		 * happens on close, not on open and _LID always returns closed.
115		 */
116		.matches = {
117			DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
118			DMI_MATCH(DMI_PRODUCT_NAME, "E2228T"),
119		},
120		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
121	},
122	{
123		/*
124		 * Razer Blade Stealth 13 late 2019, notification of the LID device
125		 * only happens on close, not on open and _LID always returns closed.
126		 */
127		.matches = {
128			DMI_MATCH(DMI_SYS_VENDOR, "Razer"),
129			DMI_MATCH(DMI_PRODUCT_NAME, "Razer Blade Stealth 13 Late 2019"),
130		},
131		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
132	},
133	{}
134};
135
136static int acpi_button_add(struct acpi_device *device);
137static void acpi_button_remove(struct acpi_device *device);
138
139#ifdef CONFIG_PM_SLEEP
140static int acpi_button_suspend(struct device *dev);
141static int acpi_button_resume(struct device *dev);
142#else
143#define acpi_button_suspend NULL
144#define acpi_button_resume NULL
145#endif
146static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
147
148static struct acpi_driver acpi_button_driver = {
149	.name = "button",
150	.class = ACPI_BUTTON_CLASS,
151	.ids = button_device_ids,
152	.ops = {
153		.add = acpi_button_add,
154		.remove = acpi_button_remove,
155	},
156	.drv.pm = &acpi_button_pm,
157};
158
159struct acpi_button {
160	unsigned int type;
161	struct input_dev *input;
162	char phys[32];			/* for input device */
163	unsigned long pushed;
164	int last_state;
165	ktime_t last_time;
166	bool suspended;
167	bool lid_state_initialized;
168};
169
170static struct acpi_device *lid_device;
171static long lid_init_state = -1;
172
173static unsigned long lid_report_interval __read_mostly = 500;
174module_param(lid_report_interval, ulong, 0644);
175MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
176
177/* FS Interface (/proc) */
178static struct proc_dir_entry *acpi_button_dir;
179static struct proc_dir_entry *acpi_lid_dir;
180
181static int acpi_lid_evaluate_state(struct acpi_device *device)
182{
183	unsigned long long lid_state;
184	acpi_status status;
185
186	status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
187	if (ACPI_FAILURE(status))
188		return -ENODEV;
189
190	return lid_state ? 1 : 0;
191}
192
193static int acpi_lid_notify_state(struct acpi_device *device, int state)
194{
195	struct acpi_button *button = acpi_driver_data(device);
196	ktime_t next_report;
197	bool do_update;
198
199	/*
200	 * In lid_init_state=ignore mode, if user opens/closes lid
201	 * frequently with "open" missing, and "last_time" is also updated
202	 * frequently, "close" cannot be delivered to the userspace.
203	 * So "last_time" is only updated after a timeout or an actual
204	 * switch.
205	 */
206	if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
207	    button->last_state != !!state)
208		do_update = true;
209	else
210		do_update = false;
211
212	next_report = ktime_add(button->last_time,
213				ms_to_ktime(lid_report_interval));
214	if (button->last_state == !!state &&
215	    ktime_after(ktime_get(), next_report)) {
216		/* Complain the buggy firmware */
217		pr_warn_once("The lid device is not compliant to SW_LID.\n");
218
219		/*
220		 * Send the unreliable complement switch event:
221		 *
222		 * On most platforms, the lid device is reliable. However
223		 * there are exceptions:
224		 * 1. Platforms returning initial lid state as "close" by
225		 *    default after booting/resuming:
226		 *     https://bugzilla.kernel.org/show_bug.cgi?id=89211
227		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106151
228		 * 2. Platforms never reporting "open" events:
229		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106941
230		 * On these buggy platforms, the usage model of the ACPI
231		 * lid device actually is:
232		 * 1. The initial returning value of _LID may not be
233		 *    reliable.
234		 * 2. The open event may not be reliable.
235		 * 3. The close event is reliable.
236		 *
237		 * But SW_LID is typed as input switch event, the input
238		 * layer checks if the event is redundant. Hence if the
239		 * state is not switched, the userspace cannot see this
240		 * platform triggered reliable event. By inserting a
241		 * complement switch event, it then is guaranteed that the
242		 * platform triggered reliable one can always be seen by
243		 * the userspace.
244		 */
245		if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
246			do_update = true;
247			/*
248			 * Do generate complement switch event for "close"
249			 * as "close" is reliable and wrong "open" won't
250			 * trigger unexpected behaviors.
251			 * Do not generate complement switch event for
252			 * "open" as "open" is not reliable and wrong
253			 * "close" will trigger unexpected behaviors.
254			 */
255			if (!state) {
256				input_report_switch(button->input,
257						    SW_LID, state);
258				input_sync(button->input);
259			}
260		}
261	}
262	/* Send the platform triggered reliable event */
263	if (do_update) {
264		acpi_handle_debug(device->handle, "ACPI LID %s\n",
265				  state ? "open" : "closed");
266		input_report_switch(button->input, SW_LID, !state);
267		input_sync(button->input);
268		button->last_state = !!state;
269		button->last_time = ktime_get();
270	}
271
272	return 0;
273}
274
275static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq,
276						     void *offset)
277{
278	struct acpi_device *device = seq->private;
279	int state;
280
281	state = acpi_lid_evaluate_state(device);
282	seq_printf(seq, "state:      %s\n",
283		   state < 0 ? "unsupported" : (state ? "open" : "closed"));
284	return 0;
285}
286
287static int acpi_button_add_fs(struct acpi_device *device)
288{
289	struct acpi_button *button = acpi_driver_data(device);
290	struct proc_dir_entry *entry = NULL;
291	int ret = 0;
292
293	/* procfs I/F for ACPI lid device only */
294	if (button->type != ACPI_BUTTON_TYPE_LID)
295		return 0;
296
297	if (acpi_button_dir || acpi_lid_dir) {
298		pr_info("More than one Lid device found!\n");
299		return -EEXIST;
300	}
301
302	/* create /proc/acpi/button */
303	acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
304	if (!acpi_button_dir)
305		return -ENODEV;
306
307	/* create /proc/acpi/button/lid */
308	acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
309	if (!acpi_lid_dir) {
310		ret = -ENODEV;
311		goto remove_button_dir;
312	}
313
314	/* create /proc/acpi/button/lid/LID/ */
315	acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
316	if (!acpi_device_dir(device)) {
317		ret = -ENODEV;
318		goto remove_lid_dir;
319	}
320
321	/* create /proc/acpi/button/lid/LID/state */
322	entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO,
323			acpi_device_dir(device), acpi_button_state_seq_show,
324			device);
325	if (!entry) {
326		ret = -ENODEV;
327		goto remove_dev_dir;
328	}
329
330done:
331	return ret;
332
333remove_dev_dir:
334	remove_proc_entry(acpi_device_bid(device),
335			  acpi_lid_dir);
336	acpi_device_dir(device) = NULL;
337remove_lid_dir:
338	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
339	acpi_lid_dir = NULL;
340remove_button_dir:
341	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
342	acpi_button_dir = NULL;
343	goto done;
344}
345
346static int acpi_button_remove_fs(struct acpi_device *device)
347{
348	struct acpi_button *button = acpi_driver_data(device);
349
350	if (button->type != ACPI_BUTTON_TYPE_LID)
351		return 0;
352
353	remove_proc_entry(ACPI_BUTTON_FILE_STATE,
354			  acpi_device_dir(device));
355	remove_proc_entry(acpi_device_bid(device),
356			  acpi_lid_dir);
357	acpi_device_dir(device) = NULL;
358	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
359	acpi_lid_dir = NULL;
360	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
361	acpi_button_dir = NULL;
362
363	return 0;
364}
365
366/* Driver Interface */
367int acpi_lid_open(void)
368{
369	if (!lid_device)
370		return -ENODEV;
371
372	return acpi_lid_evaluate_state(lid_device);
373}
374EXPORT_SYMBOL(acpi_lid_open);
375
376static int acpi_lid_update_state(struct acpi_device *device,
377				 bool signal_wakeup)
378{
379	int state;
380
381	state = acpi_lid_evaluate_state(device);
382	if (state < 0)
383		return state;
384
385	if (state && signal_wakeup)
386		acpi_pm_wakeup_event(&device->dev);
387
388	return acpi_lid_notify_state(device, state);
389}
390
391static void acpi_lid_initialize_state(struct acpi_device *device)
392{
393	struct acpi_button *button = acpi_driver_data(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, false);
401		break;
402	case ACPI_BUTTON_LID_INIT_IGNORE:
403	default:
404		break;
405	}
406
407	button->lid_state_initialized = true;
408}
409
410static void acpi_lid_notify(acpi_handle handle, u32 event, void *data)
411{
412	struct acpi_device *device = data;
413	struct acpi_button *button;
414
415	if (event != ACPI_BUTTON_NOTIFY_STATUS) {
416		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
417				  event);
418		return;
419	}
420
421	button = acpi_driver_data(device);
422	if (!button->lid_state_initialized)
423		return;
424
425	acpi_lid_update_state(device, true);
426}
427
428static void acpi_button_notify(acpi_handle handle, u32 event, void *data)
429{
430	struct acpi_device *device = data;
431	struct acpi_button *button;
432	struct input_dev *input;
433	int keycode;
434
435	if (event != ACPI_BUTTON_NOTIFY_STATUS) {
436		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
437				  event);
438		return;
439	}
440
441	acpi_pm_wakeup_event(&device->dev);
442
443	button = acpi_driver_data(device);
444	if (button->suspended)
445		return;
446
447	input = button->input;
448	keycode = test_bit(KEY_SLEEP, input->keybit) ? KEY_SLEEP : KEY_POWER;
449
450	input_report_key(input, keycode, 1);
451	input_sync(input);
452	input_report_key(input, keycode, 0);
453	input_sync(input);
454
455	acpi_bus_generate_netlink_event(device->pnp.device_class,
456					dev_name(&device->dev),
457					event, ++button->pushed);
458}
459
460static void acpi_button_notify_run(void *data)
461{
462	acpi_button_notify(NULL, ACPI_BUTTON_NOTIFY_STATUS, data);
463}
464
465static u32 acpi_button_event(void *data)
466{
467	acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_button_notify_run, data);
468	return ACPI_INTERRUPT_HANDLED;
469}
470
471#ifdef CONFIG_PM_SLEEP
472static int acpi_button_suspend(struct device *dev)
473{
474	struct acpi_device *device = to_acpi_device(dev);
475	struct acpi_button *button = acpi_driver_data(device);
476
477	button->suspended = true;
478	return 0;
479}
480
481static int acpi_button_resume(struct device *dev)
482{
483	struct input_dev *input;
484	struct acpi_device *device = to_acpi_device(dev);
485	struct acpi_button *button = acpi_driver_data(device);
486
487	button->suspended = false;
488	if (button->type == ACPI_BUTTON_TYPE_LID) {
489		button->last_state = !!acpi_lid_evaluate_state(device);
490		button->last_time = ktime_get();
491		acpi_lid_initialize_state(device);
492	}
493
494	if (button->type == ACPI_BUTTON_TYPE_POWER) {
495		input = button->input;
496		input_report_key(input, KEY_WAKEUP, 1);
497		input_sync(input);
498		input_report_key(input, KEY_WAKEUP, 0);
499		input_sync(input);
500	}
501	return 0;
502}
503#endif
504
505static int acpi_lid_input_open(struct input_dev *input)
506{
507	struct acpi_device *device = input_get_drvdata(input);
508	struct acpi_button *button = acpi_driver_data(device);
509
510	button->last_state = !!acpi_lid_evaluate_state(device);
511	button->last_time = ktime_get();
512	acpi_lid_initialize_state(device);
513
514	return 0;
515}
516
517static int acpi_button_add(struct acpi_device *device)
518{
519	acpi_notify_handler handler;
520	struct acpi_button *button;
521	struct input_dev *input;
522	const char *hid = acpi_device_hid(device);
523	acpi_status status;
524	char *name, *class;
525	int error = 0;
526
527	if (!strcmp(hid, ACPI_BUTTON_HID_LID) &&
528	     lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED)
529		return -ENODEV;
530
531	button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
532	if (!button)
533		return -ENOMEM;
534
535	device->driver_data = button;
536
537	button->input = input = input_allocate_device();
538	if (!input) {
539		error = -ENOMEM;
540		goto err_free_button;
541	}
542
543	name = acpi_device_name(device);
544	class = acpi_device_class(device);
545
546	if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
547	    !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
548		button->type = ACPI_BUTTON_TYPE_POWER;
549		handler = acpi_button_notify;
550		strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
551		sprintf(class, "%s/%s",
552			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
553	} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
554		   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
555		button->type = ACPI_BUTTON_TYPE_SLEEP;
556		handler = acpi_button_notify;
557		strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
558		sprintf(class, "%s/%s",
559			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
560	} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
561		button->type = ACPI_BUTTON_TYPE_LID;
562		handler = acpi_lid_notify;
563		strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
564		sprintf(class, "%s/%s",
565			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
566		input->open = acpi_lid_input_open;
567	} else {
568		pr_info("Unsupported hid [%s]\n", hid);
569		error = -ENODEV;
570	}
571
572	if (!error)
573		error = acpi_button_add_fs(device);
574
575	if (error) {
576		input_free_device(input);
577		goto err_free_button;
578	}
579
580	snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
581
582	input->name = name;
583	input->phys = button->phys;
584	input->id.bustype = BUS_HOST;
585	input->id.product = button->type;
586	input->dev.parent = &device->dev;
587
588	switch (button->type) {
589	case ACPI_BUTTON_TYPE_POWER:
590		input_set_capability(input, EV_KEY, KEY_POWER);
591		input_set_capability(input, EV_KEY, KEY_WAKEUP);
592		break;
593
594	case ACPI_BUTTON_TYPE_SLEEP:
595		input_set_capability(input, EV_KEY, KEY_SLEEP);
596		break;
597
598	case ACPI_BUTTON_TYPE_LID:
599		input_set_capability(input, EV_SW, SW_LID);
600		break;
601	}
602
603	input_set_drvdata(input, device);
604	error = input_register_device(input);
605	if (error)
606		goto err_remove_fs;
607
608	switch (device->device_type) {
609	case ACPI_BUS_TYPE_POWER_BUTTON:
610		status = acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
611							  acpi_button_event,
612							  device);
613		break;
614	case ACPI_BUS_TYPE_SLEEP_BUTTON:
615		status = acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
616							  acpi_button_event,
617							  device);
618		break;
619	default:
620		status = acpi_install_notify_handler(device->handle,
621						     ACPI_DEVICE_NOTIFY, handler,
622						     device);
623		break;
624	}
625	if (ACPI_FAILURE(status)) {
626		error = -ENODEV;
627		goto err_input_unregister;
628	}
629
630	if (button->type == ACPI_BUTTON_TYPE_LID) {
631		/*
632		 * This assumes there's only one lid device, or if there are
633		 * more we only care about the last one...
634		 */
635		lid_device = device;
636	}
637
638	device_init_wakeup(&device->dev, true);
639	pr_info("%s [%s]\n", name, acpi_device_bid(device));
640	return 0;
641
642err_input_unregister:
643	input_unregister_device(input);
644err_remove_fs:
645	acpi_button_remove_fs(device);
646err_free_button:
647	kfree(button);
648	return error;
649}
650
651static void acpi_button_remove(struct acpi_device *device)
652{
653	struct acpi_button *button = acpi_driver_data(device);
654
655	switch (device->device_type) {
656	case ACPI_BUS_TYPE_POWER_BUTTON:
657		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
658						acpi_button_event);
659		break;
660	case ACPI_BUS_TYPE_SLEEP_BUTTON:
661		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
662						acpi_button_event);
663		break;
664	default:
665		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
666					   button->type == ACPI_BUTTON_TYPE_LID ?
667						acpi_lid_notify :
668						acpi_button_notify);
669		break;
670	}
671	acpi_os_wait_events_complete();
672
673	acpi_button_remove_fs(device);
674	input_unregister_device(button->input);
675	kfree(button);
676}
677
678static int param_set_lid_init_state(const char *val,
679				    const struct kernel_param *kp)
680{
681	int i;
682
683	i = sysfs_match_string(lid_init_state_str, val);
684	if (i < 0)
685		return i;
686
687	lid_init_state = i;
688	pr_info("Initial lid state set to '%s'\n", lid_init_state_str[i]);
689	return 0;
690}
691
692static int param_get_lid_init_state(char *buf, const struct kernel_param *kp)
693{
694	int i, c = 0;
695
696	for (i = 0; i < ARRAY_SIZE(lid_init_state_str); i++)
697		if (i == lid_init_state)
698			c += sprintf(buf + c, "[%s] ", lid_init_state_str[i]);
699		else
700			c += sprintf(buf + c, "%s ", lid_init_state_str[i]);
701
702	buf[c - 1] = '\n'; /* Replace the final space with a newline */
703
704	return c;
705}
706
707module_param_call(lid_init_state,
708		  param_set_lid_init_state, param_get_lid_init_state,
709		  NULL, 0644);
710MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
711
712static int acpi_button_register_driver(struct acpi_driver *driver)
713{
714	const struct dmi_system_id *dmi_id;
715
716	if (lid_init_state == -1) {
717		dmi_id = dmi_first_match(dmi_lid_quirks);
718		if (dmi_id)
719			lid_init_state = (long)dmi_id->driver_data;
720		else
721			lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
722	}
723
724	/*
725	 * Modules such as nouveau.ko and i915.ko have a link time dependency
726	 * on acpi_lid_open(), and would therefore not be loadable on ACPI
727	 * capable kernels booted in non-ACPI mode if the return value of
728	 * acpi_bus_register_driver() is returned from here with ACPI disabled
729	 * when this driver is built as a module.
730	 */
731	if (acpi_disabled)
732		return 0;
733
734	return acpi_bus_register_driver(driver);
735}
736
737static void acpi_button_unregister_driver(struct acpi_driver *driver)
738{
739	if (!acpi_disabled)
740		acpi_bus_unregister_driver(driver);
741}
742
743module_driver(acpi_button_driver, acpi_button_register_driver,
744	       acpi_button_unregister_driver);
745