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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);
v5.14.15
  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		/*
 82		 * Medion Akoya E2215T, notification of the LID device only
 83		 * happens on close, not on open and _LID always returns closed.
 84		 */
 85		.matches = {
 86			DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
 87			DMI_MATCH(DMI_PRODUCT_NAME, "E2215T"),
 88		},
 89		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
 90	},
 91	{
 92		/*
 93		 * Medion Akoya E2228T, notification of the LID device only
 94		 * happens on close, not on open and _LID always returns closed.
 95		 */
 96		.matches = {
 97			DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
 98			DMI_MATCH(DMI_PRODUCT_NAME, "E2228T"),
 99		},
100		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
101	},
102	{
103		/*
104		 * Razer Blade Stealth 13 late 2019, notification of the LID device
105		 * only happens on close, not on open and _LID always returns closed.
106		 */
107		.matches = {
108			DMI_MATCH(DMI_SYS_VENDOR, "Razer"),
109			DMI_MATCH(DMI_PRODUCT_NAME, "Razer Blade Stealth 13 Late 2019"),
110		},
111		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
112	},
113	{}
114};
115
116static int acpi_button_add(struct acpi_device *device);
117static int acpi_button_remove(struct acpi_device *device);
118static void acpi_button_notify(struct acpi_device *device, u32 event);
119
120#ifdef CONFIG_PM_SLEEP
121static int acpi_button_suspend(struct device *dev);
122static int acpi_button_resume(struct device *dev);
123#else
124#define acpi_button_suspend NULL
125#define acpi_button_resume NULL
126#endif
127static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
128
129static struct acpi_driver acpi_button_driver = {
130	.name = "button",
131	.class = ACPI_BUTTON_CLASS,
132	.ids = button_device_ids,
133	.ops = {
134		.add = acpi_button_add,
135		.remove = acpi_button_remove,
136		.notify = acpi_button_notify,
137	},
138	.drv.pm = &acpi_button_pm,
139};
140
141struct acpi_button {
142	unsigned int type;
143	struct input_dev *input;
144	char phys[32];			/* for input device */
145	unsigned long pushed;
146	int last_state;
147	ktime_t last_time;
148	bool suspended;
149	bool lid_state_initialized;
150};
151
 
152static struct acpi_device *lid_device;
153static long lid_init_state = -1;
154
155static unsigned long lid_report_interval __read_mostly = 500;
156module_param(lid_report_interval, ulong, 0644);
157MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
158
159/* FS Interface (/proc) */
 
 
 
160static struct proc_dir_entry *acpi_button_dir;
161static struct proc_dir_entry *acpi_lid_dir;
162
163static int acpi_lid_evaluate_state(struct acpi_device *device)
164{
165	unsigned long long lid_state;
166	acpi_status status;
167
168	status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
169	if (ACPI_FAILURE(status))
170		return -ENODEV;
171
172	return lid_state ? 1 : 0;
173}
174
175static int acpi_lid_notify_state(struct acpi_device *device, int state)
176{
177	struct acpi_button *button = acpi_driver_data(device);
 
178	ktime_t next_report;
179	bool do_update;
180
181	/*
182	 * In lid_init_state=ignore mode, if user opens/closes lid
183	 * frequently with "open" missing, and "last_time" is also updated
184	 * frequently, "close" cannot be delivered to the userspace.
185	 * So "last_time" is only updated after a timeout or an actual
186	 * switch.
187	 */
188	if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
189	    button->last_state != !!state)
190		do_update = true;
191	else
192		do_update = false;
193
194	next_report = ktime_add(button->last_time,
195				ms_to_ktime(lid_report_interval));
196	if (button->last_state == !!state &&
197	    ktime_after(ktime_get(), next_report)) {
198		/* Complain the buggy firmware */
199		pr_warn_once("The lid device is not compliant to SW_LID.\n");
200
201		/*
202		 * Send the unreliable complement switch event:
203		 *
204		 * On most platforms, the lid device is reliable. However
205		 * there are exceptions:
206		 * 1. Platforms returning initial lid state as "close" by
207		 *    default after booting/resuming:
208		 *     https://bugzilla.kernel.org/show_bug.cgi?id=89211
209		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106151
210		 * 2. Platforms never reporting "open" events:
211		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106941
212		 * On these buggy platforms, the usage model of the ACPI
213		 * lid device actually is:
214		 * 1. The initial returning value of _LID may not be
215		 *    reliable.
216		 * 2. The open event may not be reliable.
217		 * 3. The close event is reliable.
218		 *
219		 * But SW_LID is typed as input switch event, the input
220		 * layer checks if the event is redundant. Hence if the
221		 * state is not switched, the userspace cannot see this
222		 * platform triggered reliable event. By inserting a
223		 * complement switch event, it then is guaranteed that the
224		 * platform triggered reliable one can always be seen by
225		 * the userspace.
226		 */
227		if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
228			do_update = true;
229			/*
230			 * Do generate complement switch event for "close"
231			 * as "close" is reliable and wrong "open" won't
232			 * trigger unexpected behaviors.
233			 * Do not generate complement switch event for
234			 * "open" as "open" is not reliable and wrong
235			 * "close" will trigger unexpected behaviors.
236			 */
237			if (!state) {
238				input_report_switch(button->input,
239						    SW_LID, state);
240				input_sync(button->input);
241			}
242		}
243	}
244	/* Send the platform triggered reliable event */
245	if (do_update) {
246		acpi_handle_debug(device->handle, "ACPI LID %s\n",
247				  state ? "open" : "closed");
248		input_report_switch(button->input, SW_LID, !state);
249		input_sync(button->input);
250		button->last_state = !!state;
251		button->last_time = ktime_get();
252	}
253
254	return 0;
 
 
 
 
 
 
 
 
 
 
 
255}
256
257static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq,
258						     void *offset)
259{
260	struct acpi_device *device = seq->private;
261	int state;
262
263	state = acpi_lid_evaluate_state(device);
264	seq_printf(seq, "state:      %s\n",
265		   state < 0 ? "unsupported" : (state ? "open" : "closed"));
266	return 0;
267}
268
269static int acpi_button_add_fs(struct acpi_device *device)
270{
271	struct acpi_button *button = acpi_driver_data(device);
272	struct proc_dir_entry *entry = NULL;
273	int ret = 0;
274
275	/* procfs I/F for ACPI lid device only */
276	if (button->type != ACPI_BUTTON_TYPE_LID)
277		return 0;
278
279	if (acpi_button_dir || acpi_lid_dir) {
280		pr_info("More than one Lid device found!\n");
281		return -EEXIST;
282	}
283
284	/* create /proc/acpi/button */
285	acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
286	if (!acpi_button_dir)
287		return -ENODEV;
288
289	/* create /proc/acpi/button/lid */
290	acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
291	if (!acpi_lid_dir) {
292		ret = -ENODEV;
293		goto remove_button_dir;
294	}
295
296	/* create /proc/acpi/button/lid/LID/ */
297	acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
298	if (!acpi_device_dir(device)) {
299		ret = -ENODEV;
300		goto remove_lid_dir;
301	}
302
303	/* create /proc/acpi/button/lid/LID/state */
304	entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO,
305			acpi_device_dir(device), acpi_button_state_seq_show,
306			device);
307	if (!entry) {
308		ret = -ENODEV;
309		goto remove_dev_dir;
310	}
311
312done:
313	return ret;
314
315remove_dev_dir:
316	remove_proc_entry(acpi_device_bid(device),
317			  acpi_lid_dir);
318	acpi_device_dir(device) = NULL;
319remove_lid_dir:
320	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
321	acpi_lid_dir = NULL;
322remove_button_dir:
323	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
324	acpi_button_dir = NULL;
325	goto done;
326}
327
328static int acpi_button_remove_fs(struct acpi_device *device)
329{
330	struct acpi_button *button = acpi_driver_data(device);
331
332	if (button->type != ACPI_BUTTON_TYPE_LID)
333		return 0;
334
335	remove_proc_entry(ACPI_BUTTON_FILE_STATE,
336			  acpi_device_dir(device));
337	remove_proc_entry(acpi_device_bid(device),
338			  acpi_lid_dir);
339	acpi_device_dir(device) = NULL;
340	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
341	acpi_lid_dir = NULL;
342	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
343	acpi_button_dir = NULL;
344
345	return 0;
346}
347
348/* Driver Interface */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
349int acpi_lid_open(void)
350{
351	if (!lid_device)
352		return -ENODEV;
353
354	return acpi_lid_evaluate_state(lid_device);
355}
356EXPORT_SYMBOL(acpi_lid_open);
357
358static int acpi_lid_update_state(struct acpi_device *device,
359				 bool signal_wakeup)
360{
361	int state;
362
363	state = acpi_lid_evaluate_state(device);
364	if (state < 0)
365		return state;
366
367	if (state && signal_wakeup)
368		acpi_pm_wakeup_event(&device->dev);
369
370	return acpi_lid_notify_state(device, state);
371}
372
373static void acpi_lid_initialize_state(struct acpi_device *device)
374{
375	struct acpi_button *button = acpi_driver_data(device);
376
377	switch (lid_init_state) {
378	case ACPI_BUTTON_LID_INIT_OPEN:
379		(void)acpi_lid_notify_state(device, 1);
380		break;
381	case ACPI_BUTTON_LID_INIT_METHOD:
382		(void)acpi_lid_update_state(device, false);
383		break;
384	case ACPI_BUTTON_LID_INIT_IGNORE:
385	default:
386		break;
387	}
388
389	button->lid_state_initialized = true;
390}
391
392static void acpi_button_notify(struct acpi_device *device, u32 event)
393{
394	struct acpi_button *button = acpi_driver_data(device);
395	struct input_dev *input;
 
396
397	switch (event) {
398	case ACPI_FIXED_HARDWARE_EVENT:
399		event = ACPI_BUTTON_NOTIFY_STATUS;
400		fallthrough;
401	case ACPI_BUTTON_NOTIFY_STATUS:
402		input = button->input;
403		if (button->type == ACPI_BUTTON_TYPE_LID) {
404			if (button->lid_state_initialized)
 
 
 
405				acpi_lid_update_state(device, true);
406		} else {
407			int keycode;
408
409			acpi_pm_wakeup_event(&device->dev);
410			if (button->suspended)
411				break;
412
413			keycode = test_bit(KEY_SLEEP, input->keybit) ?
414						KEY_SLEEP : KEY_POWER;
415			input_report_key(input, keycode, 1);
416			input_sync(input);
417			input_report_key(input, keycode, 0);
418			input_sync(input);
419
420			acpi_bus_generate_netlink_event(
421					device->pnp.device_class,
422					dev_name(&device->dev),
423					event, ++button->pushed);
424		}
425		break;
426	default:
427		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
428				  event);
429		break;
430	}
431}
432
433#ifdef CONFIG_PM_SLEEP
434static int acpi_button_suspend(struct device *dev)
435{
436	struct acpi_device *device = to_acpi_device(dev);
437	struct acpi_button *button = acpi_driver_data(device);
438
439	button->suspended = true;
440	return 0;
441}
442
443static int acpi_button_resume(struct device *dev)
444{
445	struct acpi_device *device = to_acpi_device(dev);
446	struct acpi_button *button = acpi_driver_data(device);
447
448	button->suspended = false;
449	if (button->type == ACPI_BUTTON_TYPE_LID) {
450		button->last_state = !!acpi_lid_evaluate_state(device);
451		button->last_time = ktime_get();
452		acpi_lid_initialize_state(device);
453	}
454	return 0;
455}
456#endif
457
458static int acpi_lid_input_open(struct input_dev *input)
459{
460	struct acpi_device *device = input_get_drvdata(input);
461	struct acpi_button *button = acpi_driver_data(device);
462
463	button->last_state = !!acpi_lid_evaluate_state(device);
464	button->last_time = ktime_get();
465	acpi_lid_initialize_state(device);
466
467	return 0;
468}
469
470static int acpi_button_add(struct acpi_device *device)
471{
472	struct acpi_button *button;
473	struct input_dev *input;
474	const char *hid = acpi_device_hid(device);
475	char *name, *class;
476	int error;
477
478	if (!strcmp(hid, ACPI_BUTTON_HID_LID) &&
479	     lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED)
480		return -ENODEV;
481
482	button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
483	if (!button)
484		return -ENOMEM;
485
486	device->driver_data = button;
487
488	button->input = input = input_allocate_device();
489	if (!input) {
490		error = -ENOMEM;
491		goto err_free_button;
492	}
493
494	name = acpi_device_name(device);
495	class = acpi_device_class(device);
496
497	if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
498	    !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
499		button->type = ACPI_BUTTON_TYPE_POWER;
500		strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
501		sprintf(class, "%s/%s",
502			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
503	} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
504		   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
505		button->type = ACPI_BUTTON_TYPE_SLEEP;
506		strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
507		sprintf(class, "%s/%s",
508			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
509	} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
510		button->type = ACPI_BUTTON_TYPE_LID;
511		strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
512		sprintf(class, "%s/%s",
513			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
514		input->open = acpi_lid_input_open;
515	} else {
516		pr_info("Unsupported hid [%s]\n", hid);
517		error = -ENODEV;
518		goto err_free_input;
519	}
520
521	error = acpi_button_add_fs(device);
522	if (error)
523		goto err_free_input;
524
525	snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
526
527	input->name = name;
528	input->phys = button->phys;
529	input->id.bustype = BUS_HOST;
530	input->id.product = button->type;
531	input->dev.parent = &device->dev;
532
533	switch (button->type) {
534	case ACPI_BUTTON_TYPE_POWER:
535		input_set_capability(input, EV_KEY, KEY_POWER);
536		break;
537
538	case ACPI_BUTTON_TYPE_SLEEP:
539		input_set_capability(input, EV_KEY, KEY_SLEEP);
540		break;
541
542	case ACPI_BUTTON_TYPE_LID:
543		input_set_capability(input, EV_SW, SW_LID);
544		break;
545	}
546
547	input_set_drvdata(input, device);
548	error = input_register_device(input);
549	if (error)
550		goto err_remove_fs;
551	if (button->type == ACPI_BUTTON_TYPE_LID) {
552		/*
553		 * This assumes there's only one lid device, or if there are
554		 * more we only care about the last one...
555		 */
556		lid_device = device;
557	}
558
559	device_init_wakeup(&device->dev, true);
560	pr_info("%s [%s]\n", name, acpi_device_bid(device));
561	return 0;
562
563 err_remove_fs:
564	acpi_button_remove_fs(device);
565 err_free_input:
566	input_free_device(input);
567 err_free_button:
568	kfree(button);
569	return error;
570}
571
572static int acpi_button_remove(struct acpi_device *device)
573{
574	struct acpi_button *button = acpi_driver_data(device);
575
576	acpi_button_remove_fs(device);
577	input_unregister_device(button->input);
578	kfree(button);
579	return 0;
580}
581
582static int param_set_lid_init_state(const char *val,
583				    const struct kernel_param *kp)
584{
585	int i;
586
587	i = sysfs_match_string(lid_init_state_str, val);
588	if (i < 0)
589		return i;
590
591	lid_init_state = i;
592	pr_info("Initial lid state set to '%s'\n", lid_init_state_str[i]);
593	return 0;
 
 
 
 
 
594}
595
596static int param_get_lid_init_state(char *buf, const struct kernel_param *kp)
 
597{
598	int i, c = 0;
599
600	for (i = 0; i < ARRAY_SIZE(lid_init_state_str); i++)
601		if (i == lid_init_state)
602			c += sprintf(buf + c, "[%s] ", lid_init_state_str[i]);
603		else
604			c += sprintf(buf + c, "%s ", lid_init_state_str[i]);
605
606	buf[c - 1] = '\n'; /* Replace the final space with a newline */
607
608	return c;
609}
610
611module_param_call(lid_init_state,
612		  param_set_lid_init_state, param_get_lid_init_state,
613		  NULL, 0644);
614MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
615
616static int acpi_button_register_driver(struct acpi_driver *driver)
617{
618	const struct dmi_system_id *dmi_id;
619
620	if (lid_init_state == -1) {
621		dmi_id = dmi_first_match(dmi_lid_quirks);
622		if (dmi_id)
623			lid_init_state = (long)dmi_id->driver_data;
624		else
625			lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
626	}
627
628	/*
629	 * Modules such as nouveau.ko and i915.ko have a link time dependency
630	 * on acpi_lid_open(), and would therefore not be loadable on ACPI
631	 * capable kernels booted in non-ACPI mode if the return value of
632	 * acpi_bus_register_driver() is returned from here with ACPI disabled
633	 * when this driver is built as a module.
634	 */
635	if (acpi_disabled)
636		return 0;
637
638	return acpi_bus_register_driver(driver);
639}
640
641static void acpi_button_unregister_driver(struct acpi_driver *driver)
642{
643	if (!acpi_disabled)
644		acpi_bus_unregister_driver(driver);
645}
646
647module_driver(acpi_button_driver, acpi_button_register_driver,
648	       acpi_button_unregister_driver);