1 /* 2 * button.c - ACPI Button Driver 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * 7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or (at 12 * your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 20 */ 21 22 #define pr_fmt(fmt) "ACPI: button: " fmt 23 24 #include <linux/kernel.h> 25 #include <linux/module.h> 26 #include <linux/init.h> 27 #include <linux/types.h> 28 #include <linux/proc_fs.h> 29 #include <linux/seq_file.h> 30 #include <linux/input.h> 31 #include <linux/slab.h> 32 #include <linux/acpi.h> 33 #include <acpi/button.h> 34 35 #define PREFIX "ACPI: " 36 37 #define ACPI_BUTTON_CLASS "button" 38 #define ACPI_BUTTON_FILE_INFO "info" 39 #define ACPI_BUTTON_FILE_STATE "state" 40 #define ACPI_BUTTON_TYPE_UNKNOWN 0x00 41 #define ACPI_BUTTON_NOTIFY_STATUS 0x80 42 43 #define ACPI_BUTTON_SUBCLASS_POWER "power" 44 #define ACPI_BUTTON_HID_POWER "PNP0C0C" 45 #define ACPI_BUTTON_DEVICE_NAME_POWER "Power Button" 46 #define ACPI_BUTTON_TYPE_POWER 0x01 47 48 #define ACPI_BUTTON_SUBCLASS_SLEEP "sleep" 49 #define ACPI_BUTTON_HID_SLEEP "PNP0C0E" 50 #define ACPI_BUTTON_DEVICE_NAME_SLEEP "Sleep Button" 51 #define ACPI_BUTTON_TYPE_SLEEP 0x03 52 53 #define ACPI_BUTTON_SUBCLASS_LID "lid" 54 #define ACPI_BUTTON_HID_LID "PNP0C0D" 55 #define ACPI_BUTTON_DEVICE_NAME_LID "Lid Switch" 56 #define ACPI_BUTTON_TYPE_LID 0x05 57 58 #define ACPI_BUTTON_LID_INIT_IGNORE 0x00 59 #define ACPI_BUTTON_LID_INIT_OPEN 0x01 60 #define ACPI_BUTTON_LID_INIT_METHOD 0x02 61 62 #define _COMPONENT ACPI_BUTTON_COMPONENT 63 ACPI_MODULE_NAME("button"); 64 65 MODULE_AUTHOR("Paul Diefenbaugh"); 66 MODULE_DESCRIPTION("ACPI Button Driver"); 67 MODULE_LICENSE("GPL"); 68 69 static const struct acpi_device_id button_device_ids[] = { 70 {ACPI_BUTTON_HID_LID, 0}, 71 {ACPI_BUTTON_HID_SLEEP, 0}, 72 {ACPI_BUTTON_HID_SLEEPF, 0}, 73 {ACPI_BUTTON_HID_POWER, 0}, 74 {ACPI_BUTTON_HID_POWERF, 0}, 75 {"", 0}, 76 }; 77 MODULE_DEVICE_TABLE(acpi, button_device_ids); 78 79 static int acpi_button_add(struct acpi_device *device); 80 static int acpi_button_remove(struct acpi_device *device); 81 static void acpi_button_notify(struct acpi_device *device, u32 event); 82 83 #ifdef CONFIG_PM_SLEEP 84 static int acpi_button_suspend(struct device *dev); 85 static int acpi_button_resume(struct device *dev); 86 #else 87 #define acpi_button_suspend NULL 88 #define acpi_button_resume NULL 89 #endif 90 static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume); 91 92 static struct acpi_driver acpi_button_driver = { 93 .name = "button", 94 .class = ACPI_BUTTON_CLASS, 95 .ids = button_device_ids, 96 .ops = { 97 .add = acpi_button_add, 98 .remove = acpi_button_remove, 99 .notify = acpi_button_notify, 100 }, 101 .drv.pm = &acpi_button_pm, 102 }; 103 104 struct acpi_button { 105 unsigned int type; 106 struct input_dev *input; 107 char phys[32]; /* for input device */ 108 unsigned long pushed; 109 int last_state; 110 ktime_t last_time; 111 bool suspended; 112 }; 113 114 static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier); 115 static struct acpi_device *lid_device; 116 static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD; 117 118 static unsigned long lid_report_interval __read_mostly = 500; 119 module_param(lid_report_interval, ulong, 0644); 120 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events"); 121 122 /* -------------------------------------------------------------------------- 123 FS Interface (/proc) 124 -------------------------------------------------------------------------- */ 125 126 static struct proc_dir_entry *acpi_button_dir; 127 static struct proc_dir_entry *acpi_lid_dir; 128 129 static int acpi_lid_evaluate_state(struct acpi_device *device) 130 { 131 unsigned long long lid_state; 132 acpi_status status; 133 134 status = acpi_evaluate_integer(device->handle, "_LID", NULL, &lid_state); 135 if (ACPI_FAILURE(status)) 136 return -ENODEV; 137 138 return lid_state ? 1 : 0; 139 } 140 141 static int acpi_lid_notify_state(struct acpi_device *device, int state) 142 { 143 struct acpi_button *button = acpi_driver_data(device); 144 int ret; 145 ktime_t next_report; 146 bool do_update; 147 148 /* 149 * In lid_init_state=ignore mode, if user opens/closes lid 150 * frequently with "open" missing, and "last_time" is also updated 151 * frequently, "close" cannot be delivered to the userspace. 152 * So "last_time" is only updated after a timeout or an actual 153 * switch. 154 */ 155 if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE || 156 button->last_state != !!state) 157 do_update = true; 158 else 159 do_update = false; 160 161 next_report = ktime_add(button->last_time, 162 ms_to_ktime(lid_report_interval)); 163 if (button->last_state == !!state && 164 ktime_after(ktime_get(), next_report)) { 165 /* Complain the buggy firmware */ 166 pr_warn_once("The lid device is not compliant to SW_LID.\n"); 167 168 /* 169 * Send the unreliable complement switch event: 170 * 171 * On most platforms, the lid device is reliable. However 172 * there are exceptions: 173 * 1. Platforms returning initial lid state as "close" by 174 * default after booting/resuming: 175 * https://bugzilla.kernel.org/show_bug.cgi?id=89211 176 * https://bugzilla.kernel.org/show_bug.cgi?id=106151 177 * 2. Platforms never reporting "open" events: 178 * https://bugzilla.kernel.org/show_bug.cgi?id=106941 179 * On these buggy platforms, the usage model of the ACPI 180 * lid device actually is: 181 * 1. The initial returning value of _LID may not be 182 * reliable. 183 * 2. The open event may not be reliable. 184 * 3. The close event is reliable. 185 * 186 * But SW_LID is typed as input switch event, the input 187 * layer checks if the event is redundant. Hence if the 188 * state is not switched, the userspace cannot see this 189 * platform triggered reliable event. By inserting a 190 * complement switch event, it then is guaranteed that the 191 * platform triggered reliable one can always be seen by 192 * the userspace. 193 */ 194 if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) { 195 do_update = true; 196 /* 197 * Do generate complement switch event for "close" 198 * as "close" is reliable and wrong "open" won't 199 * trigger unexpected behaviors. 200 * Do not generate complement switch event for 201 * "open" as "open" is not reliable and wrong 202 * "close" will trigger unexpected behaviors. 203 */ 204 if (!state) { 205 input_report_switch(button->input, 206 SW_LID, state); 207 input_sync(button->input); 208 } 209 } 210 } 211 /* Send the platform triggered reliable event */ 212 if (do_update) { 213 input_report_switch(button->input, SW_LID, !state); 214 input_sync(button->input); 215 button->last_state = !!state; 216 button->last_time = ktime_get(); 217 } 218 219 if (state) 220 acpi_pm_wakeup_event(&device->dev); 221 222 ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device); 223 if (ret == NOTIFY_DONE) 224 ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, 225 device); 226 if (ret == NOTIFY_DONE || ret == NOTIFY_OK) { 227 /* 228 * It is also regarded as success if the notifier_chain 229 * returns NOTIFY_OK or NOTIFY_DONE. 230 */ 231 ret = 0; 232 } 233 return ret; 234 } 235 236 static int acpi_button_state_seq_show(struct seq_file *seq, void *offset) 237 { 238 struct acpi_device *device = seq->private; 239 int state; 240 241 state = acpi_lid_evaluate_state(device); 242 seq_printf(seq, "state: %s\n", 243 state < 0 ? "unsupported" : (state ? "open" : "closed")); 244 return 0; 245 } 246 247 static int acpi_button_state_open_fs(struct inode *inode, struct file *file) 248 { 249 return single_open(file, acpi_button_state_seq_show, PDE_DATA(inode)); 250 } 251 252 static const struct file_operations acpi_button_state_fops = { 253 .owner = THIS_MODULE, 254 .open = acpi_button_state_open_fs, 255 .read = seq_read, 256 .llseek = seq_lseek, 257 .release = single_release, 258 }; 259 260 static int acpi_button_add_fs(struct acpi_device *device) 261 { 262 struct acpi_button *button = acpi_driver_data(device); 263 struct proc_dir_entry *entry = NULL; 264 int ret = 0; 265 266 /* procfs I/F for ACPI lid device only */ 267 if (button->type != ACPI_BUTTON_TYPE_LID) 268 return 0; 269 270 if (acpi_button_dir || acpi_lid_dir) { 271 printk(KERN_ERR PREFIX "More than one Lid device found!\n"); 272 return -EEXIST; 273 } 274 275 /* create /proc/acpi/button */ 276 acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir); 277 if (!acpi_button_dir) 278 return -ENODEV; 279 280 /* create /proc/acpi/button/lid */ 281 acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir); 282 if (!acpi_lid_dir) { 283 ret = -ENODEV; 284 goto remove_button_dir; 285 } 286 287 /* create /proc/acpi/button/lid/LID/ */ 288 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir); 289 if (!acpi_device_dir(device)) { 290 ret = -ENODEV; 291 goto remove_lid_dir; 292 } 293 294 /* create /proc/acpi/button/lid/LID/state */ 295 entry = proc_create_data(ACPI_BUTTON_FILE_STATE, 296 S_IRUGO, acpi_device_dir(device), 297 &acpi_button_state_fops, device); 298 if (!entry) { 299 ret = -ENODEV; 300 goto remove_dev_dir; 301 } 302 303 done: 304 return ret; 305 306 remove_dev_dir: 307 remove_proc_entry(acpi_device_bid(device), 308 acpi_lid_dir); 309 acpi_device_dir(device) = NULL; 310 remove_lid_dir: 311 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir); 312 acpi_lid_dir = NULL; 313 remove_button_dir: 314 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir); 315 acpi_button_dir = NULL; 316 goto done; 317 } 318 319 static int acpi_button_remove_fs(struct acpi_device *device) 320 { 321 struct acpi_button *button = acpi_driver_data(device); 322 323 if (button->type != ACPI_BUTTON_TYPE_LID) 324 return 0; 325 326 remove_proc_entry(ACPI_BUTTON_FILE_STATE, 327 acpi_device_dir(device)); 328 remove_proc_entry(acpi_device_bid(device), 329 acpi_lid_dir); 330 acpi_device_dir(device) = NULL; 331 remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir); 332 acpi_lid_dir = NULL; 333 remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir); 334 acpi_button_dir = NULL; 335 336 return 0; 337 } 338 339 /* -------------------------------------------------------------------------- 340 Driver Interface 341 -------------------------------------------------------------------------- */ 342 int acpi_lid_notifier_register(struct notifier_block *nb) 343 { 344 return blocking_notifier_chain_register(&acpi_lid_notifier, nb); 345 } 346 EXPORT_SYMBOL(acpi_lid_notifier_register); 347 348 int acpi_lid_notifier_unregister(struct notifier_block *nb) 349 { 350 return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb); 351 } 352 EXPORT_SYMBOL(acpi_lid_notifier_unregister); 353 354 int acpi_lid_open(void) 355 { 356 if (!lid_device) 357 return -ENODEV; 358 359 return acpi_lid_evaluate_state(lid_device); 360 } 361 EXPORT_SYMBOL(acpi_lid_open); 362 363 static int acpi_lid_update_state(struct acpi_device *device) 364 { 365 int state; 366 367 state = acpi_lid_evaluate_state(device); 368 if (state < 0) 369 return state; 370 371 return acpi_lid_notify_state(device, state); 372 } 373 374 static void acpi_lid_initialize_state(struct acpi_device *device) 375 { 376 switch (lid_init_state) { 377 case ACPI_BUTTON_LID_INIT_OPEN: 378 (void)acpi_lid_notify_state(device, 1); 379 break; 380 case ACPI_BUTTON_LID_INIT_METHOD: 381 (void)acpi_lid_update_state(device); 382 break; 383 case ACPI_BUTTON_LID_INIT_IGNORE: 384 default: 385 break; 386 } 387 } 388 389 static void acpi_button_notify(struct acpi_device *device, u32 event) 390 { 391 struct acpi_button *button = acpi_driver_data(device); 392 struct input_dev *input; 393 int users; 394 395 switch (event) { 396 case ACPI_FIXED_HARDWARE_EVENT: 397 event = ACPI_BUTTON_NOTIFY_STATUS; 398 /* fall through */ 399 case ACPI_BUTTON_NOTIFY_STATUS: 400 input = button->input; 401 if (button->type == ACPI_BUTTON_TYPE_LID) { 402 mutex_lock(&button->input->mutex); 403 users = button->input->users; 404 mutex_unlock(&button->input->mutex); 405 if (users) 406 acpi_lid_update_state(device); 407 } else { 408 int keycode; 409 410 acpi_pm_wakeup_event(&device->dev); 411 if (button->suspended) 412 break; 413 414 keycode = test_bit(KEY_SLEEP, input->keybit) ? 415 KEY_SLEEP : KEY_POWER; 416 input_report_key(input, keycode, 1); 417 input_sync(input); 418 input_report_key(input, keycode, 0); 419 input_sync(input); 420 421 acpi_bus_generate_netlink_event( 422 device->pnp.device_class, 423 dev_name(&device->dev), 424 event, ++button->pushed); 425 } 426 break; 427 default: 428 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 429 "Unsupported event [0x%x]\n", event)); 430 break; 431 } 432 } 433 434 #ifdef CONFIG_PM_SLEEP 435 static int acpi_button_suspend(struct device *dev) 436 { 437 struct acpi_device *device = to_acpi_device(dev); 438 struct acpi_button *button = acpi_driver_data(device); 439 440 button->suspended = true; 441 return 0; 442 } 443 444 static int acpi_button_resume(struct device *dev) 445 { 446 struct acpi_device *device = to_acpi_device(dev); 447 struct acpi_button *button = acpi_driver_data(device); 448 449 button->suspended = false; 450 if (button->type == ACPI_BUTTON_TYPE_LID && button->input->users) 451 acpi_lid_initialize_state(device); 452 return 0; 453 } 454 #endif 455 456 static int acpi_lid_input_open(struct input_dev *input) 457 { 458 struct acpi_device *device = input_get_drvdata(input); 459 struct acpi_button *button = acpi_driver_data(device); 460 461 button->last_state = !!acpi_lid_evaluate_state(device); 462 button->last_time = ktime_get(); 463 acpi_lid_initialize_state(device); 464 465 return 0; 466 } 467 468 static int acpi_button_add(struct acpi_device *device) 469 { 470 struct acpi_button *button; 471 struct input_dev *input; 472 const char *hid = acpi_device_hid(device); 473 char *name, *class; 474 int error; 475 476 button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL); 477 if (!button) 478 return -ENOMEM; 479 480 device->driver_data = button; 481 482 button->input = input = input_allocate_device(); 483 if (!input) { 484 error = -ENOMEM; 485 goto err_free_button; 486 } 487 488 name = acpi_device_name(device); 489 class = acpi_device_class(device); 490 491 if (!strcmp(hid, ACPI_BUTTON_HID_POWER) || 492 !strcmp(hid, ACPI_BUTTON_HID_POWERF)) { 493 button->type = ACPI_BUTTON_TYPE_POWER; 494 strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER); 495 sprintf(class, "%s/%s", 496 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER); 497 } else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) || 498 !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) { 499 button->type = ACPI_BUTTON_TYPE_SLEEP; 500 strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP); 501 sprintf(class, "%s/%s", 502 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP); 503 } else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) { 504 button->type = ACPI_BUTTON_TYPE_LID; 505 strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID); 506 sprintf(class, "%s/%s", 507 ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID); 508 input->open = acpi_lid_input_open; 509 } else { 510 printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid); 511 error = -ENODEV; 512 goto err_free_input; 513 } 514 515 error = acpi_button_add_fs(device); 516 if (error) 517 goto err_free_input; 518 519 snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid); 520 521 input->name = name; 522 input->phys = button->phys; 523 input->id.bustype = BUS_HOST; 524 input->id.product = button->type; 525 input->dev.parent = &device->dev; 526 527 switch (button->type) { 528 case ACPI_BUTTON_TYPE_POWER: 529 input_set_capability(input, EV_KEY, KEY_POWER); 530 break; 531 532 case ACPI_BUTTON_TYPE_SLEEP: 533 input_set_capability(input, EV_KEY, KEY_SLEEP); 534 break; 535 536 case ACPI_BUTTON_TYPE_LID: 537 input_set_capability(input, EV_SW, SW_LID); 538 break; 539 } 540 541 input_set_drvdata(input, device); 542 error = input_register_device(input); 543 if (error) 544 goto err_remove_fs; 545 if (button->type == ACPI_BUTTON_TYPE_LID) { 546 /* 547 * This assumes there's only one lid device, or if there are 548 * more we only care about the last one... 549 */ 550 lid_device = device; 551 } 552 553 device_init_wakeup(&device->dev, true); 554 printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device)); 555 return 0; 556 557 err_remove_fs: 558 acpi_button_remove_fs(device); 559 err_free_input: 560 input_free_device(input); 561 err_free_button: 562 kfree(button); 563 return error; 564 } 565 566 static int acpi_button_remove(struct acpi_device *device) 567 { 568 struct acpi_button *button = acpi_driver_data(device); 569 570 acpi_button_remove_fs(device); 571 input_unregister_device(button->input); 572 kfree(button); 573 return 0; 574 } 575 576 static int param_set_lid_init_state(const char *val, 577 const struct kernel_param *kp) 578 { 579 int result = 0; 580 581 if (!strncmp(val, "open", sizeof("open") - 1)) { 582 lid_init_state = ACPI_BUTTON_LID_INIT_OPEN; 583 pr_info("Notify initial lid state as open\n"); 584 } else if (!strncmp(val, "method", sizeof("method") - 1)) { 585 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD; 586 pr_info("Notify initial lid state with _LID return value\n"); 587 } else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) { 588 lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE; 589 pr_info("Do not notify initial lid state\n"); 590 } else 591 result = -EINVAL; 592 return result; 593 } 594 595 static int param_get_lid_init_state(char *buffer, 596 const struct kernel_param *kp) 597 { 598 switch (lid_init_state) { 599 case ACPI_BUTTON_LID_INIT_OPEN: 600 return sprintf(buffer, "open"); 601 case ACPI_BUTTON_LID_INIT_METHOD: 602 return sprintf(buffer, "method"); 603 case ACPI_BUTTON_LID_INIT_IGNORE: 604 return sprintf(buffer, "ignore"); 605 default: 606 return sprintf(buffer, "invalid"); 607 } 608 return 0; 609 } 610 611 module_param_call(lid_init_state, 612 param_set_lid_init_state, param_get_lid_init_state, 613 NULL, 0644); 614 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state"); 615 616 module_acpi_driver(acpi_button_driver); 617