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