xref: /linux/drivers/acpi/button.c (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
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 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/types.h>
26 #include <linux/proc_fs.h>
27 #include <linux/seq_file.h>
28 #include <linux/input.h>
29 #include <linux/slab.h>
30 #include <linux/acpi.h>
31 #include <acpi/button.h>
32 
33 #define PREFIX "ACPI: "
34 
35 #define ACPI_BUTTON_CLASS		"button"
36 #define ACPI_BUTTON_FILE_INFO		"info"
37 #define ACPI_BUTTON_FILE_STATE		"state"
38 #define ACPI_BUTTON_TYPE_UNKNOWN	0x00
39 #define ACPI_BUTTON_NOTIFY_STATUS	0x80
40 
41 #define ACPI_BUTTON_SUBCLASS_POWER	"power"
42 #define ACPI_BUTTON_HID_POWER		"PNP0C0C"
43 #define ACPI_BUTTON_DEVICE_NAME_POWER	"Power Button"
44 #define ACPI_BUTTON_TYPE_POWER		0x01
45 
46 #define ACPI_BUTTON_SUBCLASS_SLEEP	"sleep"
47 #define ACPI_BUTTON_HID_SLEEP		"PNP0C0E"
48 #define ACPI_BUTTON_DEVICE_NAME_SLEEP	"Sleep Button"
49 #define ACPI_BUTTON_TYPE_SLEEP		0x03
50 
51 #define ACPI_BUTTON_SUBCLASS_LID	"lid"
52 #define ACPI_BUTTON_HID_LID		"PNP0C0D"
53 #define ACPI_BUTTON_DEVICE_NAME_LID	"Lid Switch"
54 #define ACPI_BUTTON_TYPE_LID		0x05
55 
56 #define ACPI_BUTTON_LID_INIT_IGNORE	0x00
57 #define ACPI_BUTTON_LID_INIT_OPEN	0x01
58 #define ACPI_BUTTON_LID_INIT_METHOD	0x02
59 
60 #define _COMPONENT		ACPI_BUTTON_COMPONENT
61 ACPI_MODULE_NAME("button");
62 
63 MODULE_AUTHOR("Paul Diefenbaugh");
64 MODULE_DESCRIPTION("ACPI Button Driver");
65 MODULE_LICENSE("GPL");
66 
67 static const struct acpi_device_id button_device_ids[] = {
68 	{ACPI_BUTTON_HID_LID,    0},
69 	{ACPI_BUTTON_HID_SLEEP,  0},
70 	{ACPI_BUTTON_HID_SLEEPF, 0},
71 	{ACPI_BUTTON_HID_POWER,  0},
72 	{ACPI_BUTTON_HID_POWERF, 0},
73 	{"", 0},
74 };
75 MODULE_DEVICE_TABLE(acpi, button_device_ids);
76 
77 static int acpi_button_add(struct acpi_device *device);
78 static int acpi_button_remove(struct acpi_device *device);
79 static void acpi_button_notify(struct acpi_device *device, u32 event);
80 
81 #ifdef CONFIG_PM_SLEEP
82 static int acpi_button_suspend(struct device *dev);
83 static int acpi_button_resume(struct device *dev);
84 #else
85 #define acpi_button_suspend NULL
86 #define acpi_button_resume NULL
87 #endif
88 static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
89 
90 static struct acpi_driver acpi_button_driver = {
91 	.name = "button",
92 	.class = ACPI_BUTTON_CLASS,
93 	.ids = button_device_ids,
94 	.ops = {
95 		.add = acpi_button_add,
96 		.remove = acpi_button_remove,
97 		.notify = acpi_button_notify,
98 	},
99 	.drv.pm = &acpi_button_pm,
100 };
101 
102 struct acpi_button {
103 	unsigned int type;
104 	struct input_dev *input;
105 	char phys[32];			/* for input device */
106 	unsigned long pushed;
107 	bool suspended;
108 };
109 
110 static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
111 static struct acpi_device *lid_device;
112 static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
113 
114 /* --------------------------------------------------------------------------
115                               FS Interface (/proc)
116    -------------------------------------------------------------------------- */
117 
118 static struct proc_dir_entry *acpi_button_dir;
119 static struct proc_dir_entry *acpi_lid_dir;
120 
121 static int acpi_lid_evaluate_state(struct acpi_device *device)
122 {
123 	unsigned long long lid_state;
124 	acpi_status status;
125 
126 	status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state);
127 	if (ACPI_FAILURE(status))
128 		return -ENODEV;
129 
130 	return lid_state ? 1 : 0;
131 }
132 
133 static int acpi_lid_notify_state(struct acpi_device *device, int state)
134 {
135 	struct acpi_button *button = acpi_driver_data(device);
136 	int ret;
137 
138 	/* input layer checks if event is redundant */
139 	input_report_switch(button->input, SW_LID, !state);
140 	input_sync(button->input);
141 
142 	if (state)
143 		pm_wakeup_event(&device->dev, 0);
144 
145 	ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
146 	if (ret == NOTIFY_DONE)
147 		ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
148 						   device);
149 	if (ret == NOTIFY_DONE || ret == NOTIFY_OK) {
150 		/*
151 		 * It is also regarded as success if the notifier_chain
152 		 * returns NOTIFY_OK or NOTIFY_DONE.
153 		 */
154 		ret = 0;
155 	}
156 	return ret;
157 }
158 
159 static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
160 {
161 	struct acpi_device *device = seq->private;
162 	int state;
163 
164 	state = acpi_lid_evaluate_state(device);
165 	seq_printf(seq, "state:      %s\n",
166 		   state < 0 ? "unsupported" : (state ? "open" : "closed"));
167 	return 0;
168 }
169 
170 static int acpi_button_state_open_fs(struct inode *inode, struct file *file)
171 {
172 	return single_open(file, acpi_button_state_seq_show, PDE_DATA(inode));
173 }
174 
175 static const struct file_operations acpi_button_state_fops = {
176 	.owner = THIS_MODULE,
177 	.open = acpi_button_state_open_fs,
178 	.read = seq_read,
179 	.llseek = seq_lseek,
180 	.release = single_release,
181 };
182 
183 static int acpi_button_add_fs(struct acpi_device *device)
184 {
185 	struct acpi_button *button = acpi_driver_data(device);
186 	struct proc_dir_entry *entry = NULL;
187 	int ret = 0;
188 
189 	/* procfs I/F for ACPI lid device only */
190 	if (button->type != ACPI_BUTTON_TYPE_LID)
191 		return 0;
192 
193 	if (acpi_button_dir || acpi_lid_dir) {
194 		printk(KERN_ERR PREFIX "More than one Lid device found!\n");
195 		return -EEXIST;
196 	}
197 
198 	/* create /proc/acpi/button */
199 	acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
200 	if (!acpi_button_dir)
201 		return -ENODEV;
202 
203 	/* create /proc/acpi/button/lid */
204 	acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
205 	if (!acpi_lid_dir) {
206 		ret = -ENODEV;
207 		goto remove_button_dir;
208 	}
209 
210 	/* create /proc/acpi/button/lid/LID/ */
211 	acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
212 	if (!acpi_device_dir(device)) {
213 		ret = -ENODEV;
214 		goto remove_lid_dir;
215 	}
216 
217 	/* create /proc/acpi/button/lid/LID/state */
218 	entry = proc_create_data(ACPI_BUTTON_FILE_STATE,
219 				 S_IRUGO, acpi_device_dir(device),
220 				 &acpi_button_state_fops, device);
221 	if (!entry) {
222 		ret = -ENODEV;
223 		goto remove_dev_dir;
224 	}
225 
226 done:
227 	return ret;
228 
229 remove_dev_dir:
230 	remove_proc_entry(acpi_device_bid(device),
231 			  acpi_lid_dir);
232 	acpi_device_dir(device) = NULL;
233 remove_lid_dir:
234 	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
235 	acpi_lid_dir = NULL;
236 remove_button_dir:
237 	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
238 	acpi_button_dir = NULL;
239 	goto done;
240 }
241 
242 static int acpi_button_remove_fs(struct acpi_device *device)
243 {
244 	struct acpi_button *button = acpi_driver_data(device);
245 
246 	if (button->type != ACPI_BUTTON_TYPE_LID)
247 		return 0;
248 
249 	remove_proc_entry(ACPI_BUTTON_FILE_STATE,
250 			  acpi_device_dir(device));
251 	remove_proc_entry(acpi_device_bid(device),
252 			  acpi_lid_dir);
253 	acpi_device_dir(device) = NULL;
254 	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
255 	acpi_lid_dir = NULL;
256 	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
257 	acpi_button_dir = NULL;
258 
259 	return 0;
260 }
261 
262 /* --------------------------------------------------------------------------
263                                 Driver Interface
264    -------------------------------------------------------------------------- */
265 int acpi_lid_notifier_register(struct notifier_block *nb)
266 {
267 	return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
268 }
269 EXPORT_SYMBOL(acpi_lid_notifier_register);
270 
271 int acpi_lid_notifier_unregister(struct notifier_block *nb)
272 {
273 	return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
274 }
275 EXPORT_SYMBOL(acpi_lid_notifier_unregister);
276 
277 int acpi_lid_open(void)
278 {
279 	if (!lid_device)
280 		return -ENODEV;
281 
282 	return acpi_lid_evaluate_state(lid_device);
283 }
284 EXPORT_SYMBOL(acpi_lid_open);
285 
286 static int acpi_lid_update_state(struct acpi_device *device)
287 {
288 	int state;
289 
290 	state = acpi_lid_evaluate_state(device);
291 	if (state < 0)
292 		return state;
293 
294 	return acpi_lid_notify_state(device, state);
295 }
296 
297 static void acpi_lid_initialize_state(struct acpi_device *device)
298 {
299 	switch (lid_init_state) {
300 	case ACPI_BUTTON_LID_INIT_OPEN:
301 		(void)acpi_lid_notify_state(device, 1);
302 		break;
303 	case ACPI_BUTTON_LID_INIT_METHOD:
304 		(void)acpi_lid_update_state(device);
305 		break;
306 	case ACPI_BUTTON_LID_INIT_IGNORE:
307 	default:
308 		break;
309 	}
310 }
311 
312 static void acpi_button_notify(struct acpi_device *device, u32 event)
313 {
314 	struct acpi_button *button = acpi_driver_data(device);
315 	struct input_dev *input;
316 
317 	switch (event) {
318 	case ACPI_FIXED_HARDWARE_EVENT:
319 		event = ACPI_BUTTON_NOTIFY_STATUS;
320 		/* fall through */
321 	case ACPI_BUTTON_NOTIFY_STATUS:
322 		input = button->input;
323 		if (button->type == ACPI_BUTTON_TYPE_LID) {
324 			acpi_lid_update_state(device);
325 		} else {
326 			int keycode;
327 
328 			pm_wakeup_event(&device->dev, 0);
329 			if (button->suspended)
330 				break;
331 
332 			keycode = test_bit(KEY_SLEEP, input->keybit) ?
333 						KEY_SLEEP : KEY_POWER;
334 			input_report_key(input, keycode, 1);
335 			input_sync(input);
336 			input_report_key(input, keycode, 0);
337 			input_sync(input);
338 
339 			acpi_bus_generate_netlink_event(
340 					device->pnp.device_class,
341 					dev_name(&device->dev),
342 					event, ++button->pushed);
343 		}
344 		break;
345 	default:
346 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
347 				  "Unsupported event [0x%x]\n", event));
348 		break;
349 	}
350 }
351 
352 #ifdef CONFIG_PM_SLEEP
353 static int acpi_button_suspend(struct device *dev)
354 {
355 	struct acpi_device *device = to_acpi_device(dev);
356 	struct acpi_button *button = acpi_driver_data(device);
357 
358 	button->suspended = true;
359 	return 0;
360 }
361 
362 static int acpi_button_resume(struct device *dev)
363 {
364 	struct acpi_device *device = to_acpi_device(dev);
365 	struct acpi_button *button = acpi_driver_data(device);
366 
367 	button->suspended = false;
368 	if (button->type == ACPI_BUTTON_TYPE_LID)
369 		acpi_lid_initialize_state(device);
370 	return 0;
371 }
372 #endif
373 
374 static int acpi_button_add(struct acpi_device *device)
375 {
376 	struct acpi_button *button;
377 	struct input_dev *input;
378 	const char *hid = acpi_device_hid(device);
379 	char *name, *class;
380 	int error;
381 
382 	button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
383 	if (!button)
384 		return -ENOMEM;
385 
386 	device->driver_data = button;
387 
388 	button->input = input = input_allocate_device();
389 	if (!input) {
390 		error = -ENOMEM;
391 		goto err_free_button;
392 	}
393 
394 	name = acpi_device_name(device);
395 	class = acpi_device_class(device);
396 
397 	if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
398 	    !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
399 		button->type = ACPI_BUTTON_TYPE_POWER;
400 		strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
401 		sprintf(class, "%s/%s",
402 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
403 	} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
404 		   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
405 		button->type = ACPI_BUTTON_TYPE_SLEEP;
406 		strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
407 		sprintf(class, "%s/%s",
408 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
409 	} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
410 		button->type = ACPI_BUTTON_TYPE_LID;
411 		strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
412 		sprintf(class, "%s/%s",
413 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
414 	} else {
415 		printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
416 		error = -ENODEV;
417 		goto err_free_input;
418 	}
419 
420 	error = acpi_button_add_fs(device);
421 	if (error)
422 		goto err_free_input;
423 
424 	snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
425 
426 	input->name = name;
427 	input->phys = button->phys;
428 	input->id.bustype = BUS_HOST;
429 	input->id.product = button->type;
430 	input->dev.parent = &device->dev;
431 
432 	switch (button->type) {
433 	case ACPI_BUTTON_TYPE_POWER:
434 		input_set_capability(input, EV_KEY, KEY_POWER);
435 		break;
436 
437 	case ACPI_BUTTON_TYPE_SLEEP:
438 		input_set_capability(input, EV_KEY, KEY_SLEEP);
439 		break;
440 
441 	case ACPI_BUTTON_TYPE_LID:
442 		input_set_capability(input, EV_SW, SW_LID);
443 		break;
444 	}
445 
446 	error = input_register_device(input);
447 	if (error)
448 		goto err_remove_fs;
449 	if (button->type == ACPI_BUTTON_TYPE_LID) {
450 		acpi_lid_initialize_state(device);
451 		/*
452 		 * This assumes there's only one lid device, or if there are
453 		 * more we only care about the last one...
454 		 */
455 		lid_device = device;
456 	}
457 
458 	printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
459 	return 0;
460 
461  err_remove_fs:
462 	acpi_button_remove_fs(device);
463  err_free_input:
464 	input_free_device(input);
465  err_free_button:
466 	kfree(button);
467 	return error;
468 }
469 
470 static int acpi_button_remove(struct acpi_device *device)
471 {
472 	struct acpi_button *button = acpi_driver_data(device);
473 
474 	acpi_button_remove_fs(device);
475 	input_unregister_device(button->input);
476 	kfree(button);
477 	return 0;
478 }
479 
480 static int param_set_lid_init_state(const char *val, struct kernel_param *kp)
481 {
482 	int result = 0;
483 
484 	if (!strncmp(val, "open", sizeof("open") - 1)) {
485 		lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
486 		pr_info("Notify initial lid state as open\n");
487 	} else if (!strncmp(val, "method", sizeof("method") - 1)) {
488 		lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
489 		pr_info("Notify initial lid state with _LID return value\n");
490 	} else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
491 		lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
492 		pr_info("Do not notify initial lid state\n");
493 	} else
494 		result = -EINVAL;
495 	return result;
496 }
497 
498 static int param_get_lid_init_state(char *buffer, struct kernel_param *kp)
499 {
500 	switch (lid_init_state) {
501 	case ACPI_BUTTON_LID_INIT_OPEN:
502 		return sprintf(buffer, "open");
503 	case ACPI_BUTTON_LID_INIT_METHOD:
504 		return sprintf(buffer, "method");
505 	case ACPI_BUTTON_LID_INIT_IGNORE:
506 		return sprintf(buffer, "ignore");
507 	default:
508 		return sprintf(buffer, "invalid");
509 	}
510 	return 0;
511 }
512 
513 module_param_call(lid_init_state,
514 		  param_set_lid_init_state, param_get_lid_init_state,
515 		  NULL, 0644);
516 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
517 
518 module_acpi_driver(acpi_button_driver);
519