xref: /openbmc/linux/drivers/acpi/button.c (revision 77a87824)
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 remove_button_dir:
236 	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
237 	goto done;
238 }
239 
240 static int acpi_button_remove_fs(struct acpi_device *device)
241 {
242 	struct acpi_button *button = acpi_driver_data(device);
243 
244 	if (button->type != ACPI_BUTTON_TYPE_LID)
245 		return 0;
246 
247 	remove_proc_entry(ACPI_BUTTON_FILE_STATE,
248 			  acpi_device_dir(device));
249 	remove_proc_entry(acpi_device_bid(device),
250 			  acpi_lid_dir);
251 	acpi_device_dir(device) = NULL;
252 	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
253 	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
254 
255 	return 0;
256 }
257 
258 /* --------------------------------------------------------------------------
259                                 Driver Interface
260    -------------------------------------------------------------------------- */
261 int acpi_lid_notifier_register(struct notifier_block *nb)
262 {
263 	return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
264 }
265 EXPORT_SYMBOL(acpi_lid_notifier_register);
266 
267 int acpi_lid_notifier_unregister(struct notifier_block *nb)
268 {
269 	return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
270 }
271 EXPORT_SYMBOL(acpi_lid_notifier_unregister);
272 
273 int acpi_lid_open(void)
274 {
275 	if (!lid_device)
276 		return -ENODEV;
277 
278 	return acpi_lid_evaluate_state(lid_device);
279 }
280 EXPORT_SYMBOL(acpi_lid_open);
281 
282 static int acpi_lid_update_state(struct acpi_device *device)
283 {
284 	int state;
285 
286 	state = acpi_lid_evaluate_state(device);
287 	if (state < 0)
288 		return state;
289 
290 	return acpi_lid_notify_state(device, state);
291 }
292 
293 static void acpi_lid_initialize_state(struct acpi_device *device)
294 {
295 	switch (lid_init_state) {
296 	case ACPI_BUTTON_LID_INIT_OPEN:
297 		(void)acpi_lid_notify_state(device, 1);
298 		break;
299 	case ACPI_BUTTON_LID_INIT_METHOD:
300 		(void)acpi_lid_update_state(device);
301 		break;
302 	case ACPI_BUTTON_LID_INIT_IGNORE:
303 	default:
304 		break;
305 	}
306 }
307 
308 static void acpi_button_notify(struct acpi_device *device, u32 event)
309 {
310 	struct acpi_button *button = acpi_driver_data(device);
311 	struct input_dev *input;
312 
313 	switch (event) {
314 	case ACPI_FIXED_HARDWARE_EVENT:
315 		event = ACPI_BUTTON_NOTIFY_STATUS;
316 		/* fall through */
317 	case ACPI_BUTTON_NOTIFY_STATUS:
318 		input = button->input;
319 		if (button->type == ACPI_BUTTON_TYPE_LID) {
320 			acpi_lid_update_state(device);
321 		} else {
322 			int keycode;
323 
324 			pm_wakeup_event(&device->dev, 0);
325 			if (button->suspended)
326 				break;
327 
328 			keycode = test_bit(KEY_SLEEP, input->keybit) ?
329 						KEY_SLEEP : KEY_POWER;
330 			input_report_key(input, keycode, 1);
331 			input_sync(input);
332 			input_report_key(input, keycode, 0);
333 			input_sync(input);
334 
335 			acpi_bus_generate_netlink_event(
336 					device->pnp.device_class,
337 					dev_name(&device->dev),
338 					event, ++button->pushed);
339 		}
340 		break;
341 	default:
342 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
343 				  "Unsupported event [0x%x]\n", event));
344 		break;
345 	}
346 }
347 
348 #ifdef CONFIG_PM_SLEEP
349 static int acpi_button_suspend(struct device *dev)
350 {
351 	struct acpi_device *device = to_acpi_device(dev);
352 	struct acpi_button *button = acpi_driver_data(device);
353 
354 	button->suspended = true;
355 	return 0;
356 }
357 
358 static int acpi_button_resume(struct device *dev)
359 {
360 	struct acpi_device *device = to_acpi_device(dev);
361 	struct acpi_button *button = acpi_driver_data(device);
362 
363 	button->suspended = false;
364 	if (button->type == ACPI_BUTTON_TYPE_LID)
365 		acpi_lid_initialize_state(device);
366 	return 0;
367 }
368 #endif
369 
370 static int acpi_button_add(struct acpi_device *device)
371 {
372 	struct acpi_button *button;
373 	struct input_dev *input;
374 	const char *hid = acpi_device_hid(device);
375 	char *name, *class;
376 	int error;
377 
378 	button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
379 	if (!button)
380 		return -ENOMEM;
381 
382 	device->driver_data = button;
383 
384 	button->input = input = input_allocate_device();
385 	if (!input) {
386 		error = -ENOMEM;
387 		goto err_free_button;
388 	}
389 
390 	name = acpi_device_name(device);
391 	class = acpi_device_class(device);
392 
393 	if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
394 	    !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
395 		button->type = ACPI_BUTTON_TYPE_POWER;
396 		strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
397 		sprintf(class, "%s/%s",
398 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
399 	} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
400 		   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
401 		button->type = ACPI_BUTTON_TYPE_SLEEP;
402 		strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
403 		sprintf(class, "%s/%s",
404 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
405 	} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
406 		button->type = ACPI_BUTTON_TYPE_LID;
407 		strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
408 		sprintf(class, "%s/%s",
409 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
410 	} else {
411 		printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
412 		error = -ENODEV;
413 		goto err_free_input;
414 	}
415 
416 	error = acpi_button_add_fs(device);
417 	if (error)
418 		goto err_free_input;
419 
420 	snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
421 
422 	input->name = name;
423 	input->phys = button->phys;
424 	input->id.bustype = BUS_HOST;
425 	input->id.product = button->type;
426 	input->dev.parent = &device->dev;
427 
428 	switch (button->type) {
429 	case ACPI_BUTTON_TYPE_POWER:
430 		input_set_capability(input, EV_KEY, KEY_POWER);
431 		break;
432 
433 	case ACPI_BUTTON_TYPE_SLEEP:
434 		input_set_capability(input, EV_KEY, KEY_SLEEP);
435 		break;
436 
437 	case ACPI_BUTTON_TYPE_LID:
438 		input_set_capability(input, EV_SW, SW_LID);
439 		break;
440 	}
441 
442 	error = input_register_device(input);
443 	if (error)
444 		goto err_remove_fs;
445 	if (button->type == ACPI_BUTTON_TYPE_LID) {
446 		acpi_lid_initialize_state(device);
447 		/*
448 		 * This assumes there's only one lid device, or if there are
449 		 * more we only care about the last one...
450 		 */
451 		lid_device = device;
452 	}
453 
454 	printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
455 	return 0;
456 
457  err_remove_fs:
458 	acpi_button_remove_fs(device);
459  err_free_input:
460 	input_free_device(input);
461  err_free_button:
462 	kfree(button);
463 	return error;
464 }
465 
466 static int acpi_button_remove(struct acpi_device *device)
467 {
468 	struct acpi_button *button = acpi_driver_data(device);
469 
470 	acpi_button_remove_fs(device);
471 	input_unregister_device(button->input);
472 	kfree(button);
473 	return 0;
474 }
475 
476 static int param_set_lid_init_state(const char *val, struct kernel_param *kp)
477 {
478 	int result = 0;
479 
480 	if (!strncmp(val, "open", sizeof("open") - 1)) {
481 		lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
482 		pr_info("Notify initial lid state as open\n");
483 	} else if (!strncmp(val, "method", sizeof("method") - 1)) {
484 		lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
485 		pr_info("Notify initial lid state with _LID return value\n");
486 	} else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
487 		lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
488 		pr_info("Do not notify initial lid state\n");
489 	} else
490 		result = -EINVAL;
491 	return result;
492 }
493 
494 static int param_get_lid_init_state(char *buffer, struct kernel_param *kp)
495 {
496 	switch (lid_init_state) {
497 	case ACPI_BUTTON_LID_INIT_OPEN:
498 		return sprintf(buffer, "open");
499 	case ACPI_BUTTON_LID_INIT_METHOD:
500 		return sprintf(buffer, "method");
501 	case ACPI_BUTTON_LID_INIT_IGNORE:
502 		return sprintf(buffer, "ignore");
503 	default:
504 		return sprintf(buffer, "invalid");
505 	}
506 	return 0;
507 }
508 
509 module_param_call(lid_init_state,
510 		  param_set_lid_init_state, param_get_lid_init_state,
511 		  NULL, 0644);
512 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
513 
514 module_acpi_driver(acpi_button_driver);
515