1 /* 2 * drivers/acpi/device_sysfs.c - ACPI device sysfs attributes and modalias. 3 * 4 * Copyright (C) 2015, Intel Corp. 5 * Author: Mika Westerberg <mika.westerberg@linux.intel.com> 6 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 7 * 8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as published 12 * by the Free Software Foundation. 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/acpi.h> 23 #include <linux/device.h> 24 #include <linux/export.h> 25 #include <linux/nls.h> 26 27 #include "internal.h" 28 29 static ssize_t acpi_object_path(acpi_handle handle, char *buf) 30 { 31 struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL}; 32 int result; 33 34 result = acpi_get_name(handle, ACPI_FULL_PATHNAME, &path); 35 if (result) 36 return result; 37 38 result = sprintf(buf, "%s\n", (char *)path.pointer); 39 kfree(path.pointer); 40 return result; 41 } 42 43 struct acpi_data_node_attr { 44 struct attribute attr; 45 ssize_t (*show)(struct acpi_data_node *, char *); 46 ssize_t (*store)(struct acpi_data_node *, const char *, size_t count); 47 }; 48 49 #define DATA_NODE_ATTR(_name) \ 50 static struct acpi_data_node_attr data_node_##_name = \ 51 __ATTR(_name, 0444, data_node_show_##_name, NULL) 52 53 static ssize_t data_node_show_path(struct acpi_data_node *dn, char *buf) 54 { 55 return dn->handle ? acpi_object_path(dn->handle, buf) : 0; 56 } 57 58 DATA_NODE_ATTR(path); 59 60 static struct attribute *acpi_data_node_default_attrs[] = { 61 &data_node_path.attr, 62 NULL 63 }; 64 65 #define to_data_node(k) container_of(k, struct acpi_data_node, kobj) 66 #define to_attr(a) container_of(a, struct acpi_data_node_attr, attr) 67 68 static ssize_t acpi_data_node_attr_show(struct kobject *kobj, 69 struct attribute *attr, char *buf) 70 { 71 struct acpi_data_node *dn = to_data_node(kobj); 72 struct acpi_data_node_attr *dn_attr = to_attr(attr); 73 74 return dn_attr->show ? dn_attr->show(dn, buf) : -ENXIO; 75 } 76 77 static const struct sysfs_ops acpi_data_node_sysfs_ops = { 78 .show = acpi_data_node_attr_show, 79 }; 80 81 static void acpi_data_node_release(struct kobject *kobj) 82 { 83 struct acpi_data_node *dn = to_data_node(kobj); 84 complete(&dn->kobj_done); 85 } 86 87 static struct kobj_type acpi_data_node_ktype = { 88 .sysfs_ops = &acpi_data_node_sysfs_ops, 89 .default_attrs = acpi_data_node_default_attrs, 90 .release = acpi_data_node_release, 91 }; 92 93 static void acpi_expose_nondev_subnodes(struct kobject *kobj, 94 struct acpi_device_data *data) 95 { 96 struct list_head *list = &data->subnodes; 97 struct acpi_data_node *dn; 98 99 if (list_empty(list)) 100 return; 101 102 list_for_each_entry(dn, list, sibling) { 103 int ret; 104 105 init_completion(&dn->kobj_done); 106 ret = kobject_init_and_add(&dn->kobj, &acpi_data_node_ktype, 107 kobj, "%s", dn->name); 108 if (!ret) 109 acpi_expose_nondev_subnodes(&dn->kobj, &dn->data); 110 else if (dn->handle) 111 acpi_handle_err(dn->handle, "Failed to expose (%d)\n", ret); 112 } 113 } 114 115 static void acpi_hide_nondev_subnodes(struct acpi_device_data *data) 116 { 117 struct list_head *list = &data->subnodes; 118 struct acpi_data_node *dn; 119 120 if (list_empty(list)) 121 return; 122 123 list_for_each_entry_reverse(dn, list, sibling) { 124 acpi_hide_nondev_subnodes(&dn->data); 125 kobject_put(&dn->kobj); 126 } 127 } 128 129 /** 130 * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent 131 * @acpi_dev: ACPI device object. 132 * @modalias: Buffer to print into. 133 * @size: Size of the buffer. 134 * 135 * Creates hid/cid(s) string needed for modalias and uevent 136 * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get: 137 * char *modalias: "acpi:IBM0001:ACPI0001" 138 * Return: 0: no _HID and no _CID 139 * -EINVAL: output error 140 * -ENOMEM: output is truncated 141 */ 142 static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias, 143 int size) 144 { 145 int len; 146 int count; 147 struct acpi_hardware_id *id; 148 149 /* 150 * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should 151 * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the 152 * device's list. 153 */ 154 count = 0; 155 list_for_each_entry(id, &acpi_dev->pnp.ids, list) 156 if (strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 157 count++; 158 159 if (!count) 160 return 0; 161 162 len = snprintf(modalias, size, "acpi:"); 163 if (len <= 0) 164 return len; 165 166 size -= len; 167 168 list_for_each_entry(id, &acpi_dev->pnp.ids, list) { 169 if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 170 continue; 171 172 count = snprintf(&modalias[len], size, "%s:", id->id); 173 if (count < 0) 174 return -EINVAL; 175 176 if (count >= size) 177 return -ENOMEM; 178 179 len += count; 180 size -= count; 181 } 182 modalias[len] = '\0'; 183 return len; 184 } 185 186 /** 187 * create_of_modalias - Creates DT compatible string for modalias and uevent 188 * @acpi_dev: ACPI device object. 189 * @modalias: Buffer to print into. 190 * @size: Size of the buffer. 191 * 192 * Expose DT compatible modalias as of:NnameTCcompatible. This function should 193 * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of 194 * ACPI/PNP IDs. 195 */ 196 static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias, 197 int size) 198 { 199 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; 200 const union acpi_object *of_compatible, *obj; 201 int len, count; 202 int i, nval; 203 char *c; 204 205 acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf); 206 /* DT strings are all in lower case */ 207 for (c = buf.pointer; *c != '\0'; c++) 208 *c = tolower(*c); 209 210 len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); 211 ACPI_FREE(buf.pointer); 212 213 if (len <= 0) 214 return len; 215 216 of_compatible = acpi_dev->data.of_compatible; 217 if (of_compatible->type == ACPI_TYPE_PACKAGE) { 218 nval = of_compatible->package.count; 219 obj = of_compatible->package.elements; 220 } else { /* Must be ACPI_TYPE_STRING. */ 221 nval = 1; 222 obj = of_compatible; 223 } 224 for (i = 0; i < nval; i++, obj++) { 225 count = snprintf(&modalias[len], size, "C%s", 226 obj->string.pointer); 227 if (count < 0) 228 return -EINVAL; 229 230 if (count >= size) 231 return -ENOMEM; 232 233 len += count; 234 size -= count; 235 } 236 modalias[len] = '\0'; 237 return len; 238 } 239 240 int __acpi_device_uevent_modalias(struct acpi_device *adev, 241 struct kobj_uevent_env *env) 242 { 243 int len; 244 245 if (!adev) 246 return -ENODEV; 247 248 if (list_empty(&adev->pnp.ids)) 249 return 0; 250 251 if (add_uevent_var(env, "MODALIAS=")) 252 return -ENOMEM; 253 254 len = create_pnp_modalias(adev, &env->buf[env->buflen - 1], 255 sizeof(env->buf) - env->buflen); 256 if (len < 0) 257 return len; 258 259 env->buflen += len; 260 if (!adev->data.of_compatible) 261 return 0; 262 263 if (len > 0 && add_uevent_var(env, "MODALIAS=")) 264 return -ENOMEM; 265 266 len = create_of_modalias(adev, &env->buf[env->buflen - 1], 267 sizeof(env->buf) - env->buflen); 268 if (len < 0) 269 return len; 270 271 env->buflen += len; 272 273 return 0; 274 } 275 276 /** 277 * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices. 278 * 279 * Create the uevent modalias field for ACPI-enumerated devices. 280 * 281 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 282 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 283 */ 284 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) 285 { 286 return __acpi_device_uevent_modalias(acpi_companion_match(dev), env); 287 } 288 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias); 289 290 static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size) 291 { 292 int len, count; 293 294 if (!adev) 295 return -ENODEV; 296 297 if (list_empty(&adev->pnp.ids)) 298 return 0; 299 300 len = create_pnp_modalias(adev, buf, size - 1); 301 if (len < 0) { 302 return len; 303 } else if (len > 0) { 304 buf[len++] = '\n'; 305 size -= len; 306 } 307 if (!adev->data.of_compatible) 308 return len; 309 310 count = create_of_modalias(adev, buf + len, size - 1); 311 if (count < 0) { 312 return count; 313 } else if (count > 0) { 314 len += count; 315 buf[len++] = '\n'; 316 } 317 318 return len; 319 } 320 321 /** 322 * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices. 323 * 324 * Create the modalias sysfs attribute for ACPI-enumerated devices. 325 * 326 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 327 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 328 */ 329 int acpi_device_modalias(struct device *dev, char *buf, int size) 330 { 331 return __acpi_device_modalias(acpi_companion_match(dev), buf, size); 332 } 333 EXPORT_SYMBOL_GPL(acpi_device_modalias); 334 335 static ssize_t 336 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) 337 { 338 return __acpi_device_modalias(to_acpi_device(dev), buf, 1024); 339 } 340 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL); 341 342 static ssize_t real_power_state_show(struct device *dev, 343 struct device_attribute *attr, char *buf) 344 { 345 struct acpi_device *adev = to_acpi_device(dev); 346 int state; 347 int ret; 348 349 ret = acpi_device_get_power(adev, &state); 350 if (ret) 351 return ret; 352 353 return sprintf(buf, "%s\n", acpi_power_state_string(state)); 354 } 355 356 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL); 357 358 static ssize_t power_state_show(struct device *dev, 359 struct device_attribute *attr, char *buf) 360 { 361 struct acpi_device *adev = to_acpi_device(dev); 362 363 return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state)); 364 } 365 366 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL); 367 368 static ssize_t 369 acpi_eject_store(struct device *d, struct device_attribute *attr, 370 const char *buf, size_t count) 371 { 372 struct acpi_device *acpi_device = to_acpi_device(d); 373 acpi_object_type not_used; 374 acpi_status status; 375 376 if (!count || buf[0] != '1') 377 return -EINVAL; 378 379 if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) 380 && !acpi_device->driver) 381 return -ENODEV; 382 383 status = acpi_get_type(acpi_device->handle, ¬_used); 384 if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) 385 return -ENODEV; 386 387 get_device(&acpi_device->dev); 388 status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT); 389 if (ACPI_SUCCESS(status)) 390 return count; 391 392 put_device(&acpi_device->dev); 393 acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT, 394 ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL); 395 return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; 396 } 397 398 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store); 399 400 static ssize_t 401 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) 402 { 403 struct acpi_device *acpi_dev = to_acpi_device(dev); 404 405 return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev)); 406 } 407 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL); 408 409 static ssize_t acpi_device_uid_show(struct device *dev, 410 struct device_attribute *attr, char *buf) 411 { 412 struct acpi_device *acpi_dev = to_acpi_device(dev); 413 414 return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id); 415 } 416 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL); 417 418 static ssize_t acpi_device_adr_show(struct device *dev, 419 struct device_attribute *attr, char *buf) 420 { 421 struct acpi_device *acpi_dev = to_acpi_device(dev); 422 423 return sprintf(buf, "0x%08x\n", 424 (unsigned int)(acpi_dev->pnp.bus_address)); 425 } 426 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL); 427 428 static ssize_t acpi_device_path_show(struct device *dev, 429 struct device_attribute *attr, char *buf) 430 { 431 struct acpi_device *acpi_dev = to_acpi_device(dev); 432 433 return acpi_object_path(acpi_dev->handle, buf); 434 } 435 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL); 436 437 /* sysfs file that shows description text from the ACPI _STR method */ 438 static ssize_t description_show(struct device *dev, 439 struct device_attribute *attr, 440 char *buf) { 441 struct acpi_device *acpi_dev = to_acpi_device(dev); 442 int result; 443 444 if (acpi_dev->pnp.str_obj == NULL) 445 return 0; 446 447 /* 448 * The _STR object contains a Unicode identifier for a device. 449 * We need to convert to utf-8 so it can be displayed. 450 */ 451 result = utf16s_to_utf8s( 452 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer, 453 acpi_dev->pnp.str_obj->buffer.length, 454 UTF16_LITTLE_ENDIAN, buf, 455 PAGE_SIZE); 456 457 buf[result++] = '\n'; 458 459 return result; 460 } 461 static DEVICE_ATTR(description, 0444, description_show, NULL); 462 463 static ssize_t 464 acpi_device_sun_show(struct device *dev, struct device_attribute *attr, 465 char *buf) { 466 struct acpi_device *acpi_dev = to_acpi_device(dev); 467 acpi_status status; 468 unsigned long long sun; 469 470 status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun); 471 if (ACPI_FAILURE(status)) 472 return -EIO; 473 474 return sprintf(buf, "%llu\n", sun); 475 } 476 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL); 477 478 static ssize_t 479 acpi_device_hrv_show(struct device *dev, struct device_attribute *attr, 480 char *buf) { 481 struct acpi_device *acpi_dev = to_acpi_device(dev); 482 acpi_status status; 483 unsigned long long hrv; 484 485 status = acpi_evaluate_integer(acpi_dev->handle, "_HRV", NULL, &hrv); 486 if (ACPI_FAILURE(status)) 487 return -EIO; 488 489 return sprintf(buf, "%llu\n", hrv); 490 } 491 static DEVICE_ATTR(hrv, 0444, acpi_device_hrv_show, NULL); 492 493 static ssize_t status_show(struct device *dev, struct device_attribute *attr, 494 char *buf) { 495 struct acpi_device *acpi_dev = to_acpi_device(dev); 496 acpi_status status; 497 unsigned long long sta; 498 499 status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta); 500 if (ACPI_FAILURE(status)) 501 return -EIO; 502 503 return sprintf(buf, "%llu\n", sta); 504 } 505 static DEVICE_ATTR_RO(status); 506 507 /** 508 * acpi_device_setup_files - Create sysfs attributes of an ACPI device. 509 * @dev: ACPI device object. 510 */ 511 int acpi_device_setup_files(struct acpi_device *dev) 512 { 513 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 514 acpi_status status; 515 int result = 0; 516 517 /* 518 * Devices gotten from FADT don't have a "path" attribute 519 */ 520 if (dev->handle) { 521 result = device_create_file(&dev->dev, &dev_attr_path); 522 if (result) 523 goto end; 524 } 525 526 if (!list_empty(&dev->pnp.ids)) { 527 result = device_create_file(&dev->dev, &dev_attr_hid); 528 if (result) 529 goto end; 530 531 result = device_create_file(&dev->dev, &dev_attr_modalias); 532 if (result) 533 goto end; 534 } 535 536 /* 537 * If device has _STR, 'description' file is created 538 */ 539 if (acpi_has_method(dev->handle, "_STR")) { 540 status = acpi_evaluate_object(dev->handle, "_STR", 541 NULL, &buffer); 542 if (ACPI_FAILURE(status)) 543 buffer.pointer = NULL; 544 dev->pnp.str_obj = buffer.pointer; 545 result = device_create_file(&dev->dev, &dev_attr_description); 546 if (result) 547 goto end; 548 } 549 550 if (dev->pnp.type.bus_address) 551 result = device_create_file(&dev->dev, &dev_attr_adr); 552 if (dev->pnp.unique_id) 553 result = device_create_file(&dev->dev, &dev_attr_uid); 554 555 if (acpi_has_method(dev->handle, "_SUN")) { 556 result = device_create_file(&dev->dev, &dev_attr_sun); 557 if (result) 558 goto end; 559 } 560 561 if (acpi_has_method(dev->handle, "_HRV")) { 562 result = device_create_file(&dev->dev, &dev_attr_hrv); 563 if (result) 564 goto end; 565 } 566 567 if (acpi_has_method(dev->handle, "_STA")) { 568 result = device_create_file(&dev->dev, &dev_attr_status); 569 if (result) 570 goto end; 571 } 572 573 /* 574 * If device has _EJ0, 'eject' file is created that is used to trigger 575 * hot-removal function from userland. 576 */ 577 if (acpi_has_method(dev->handle, "_EJ0")) { 578 result = device_create_file(&dev->dev, &dev_attr_eject); 579 if (result) 580 return result; 581 } 582 583 if (dev->flags.power_manageable) { 584 result = device_create_file(&dev->dev, &dev_attr_power_state); 585 if (result) 586 return result; 587 588 if (dev->power.flags.power_resources) 589 result = device_create_file(&dev->dev, 590 &dev_attr_real_power_state); 591 } 592 593 acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data); 594 595 end: 596 return result; 597 } 598 599 /** 600 * acpi_device_remove_files - Remove sysfs attributes of an ACPI device. 601 * @dev: ACPI device object. 602 */ 603 void acpi_device_remove_files(struct acpi_device *dev) 604 { 605 acpi_hide_nondev_subnodes(&dev->data); 606 607 if (dev->flags.power_manageable) { 608 device_remove_file(&dev->dev, &dev_attr_power_state); 609 if (dev->power.flags.power_resources) 610 device_remove_file(&dev->dev, 611 &dev_attr_real_power_state); 612 } 613 614 /* 615 * If device has _STR, remove 'description' file 616 */ 617 if (acpi_has_method(dev->handle, "_STR")) { 618 kfree(dev->pnp.str_obj); 619 device_remove_file(&dev->dev, &dev_attr_description); 620 } 621 /* 622 * If device has _EJ0, remove 'eject' file. 623 */ 624 if (acpi_has_method(dev->handle, "_EJ0")) 625 device_remove_file(&dev->dev, &dev_attr_eject); 626 627 if (acpi_has_method(dev->handle, "_SUN")) 628 device_remove_file(&dev->dev, &dev_attr_sun); 629 630 if (acpi_has_method(dev->handle, "_HRV")) 631 device_remove_file(&dev->dev, &dev_attr_hrv); 632 633 if (dev->pnp.unique_id) 634 device_remove_file(&dev->dev, &dev_attr_uid); 635 if (dev->pnp.type.bus_address) 636 device_remove_file(&dev->dev, &dev_attr_adr); 637 device_remove_file(&dev->dev, &dev_attr_modalias); 638 device_remove_file(&dev->dev, &dev_attr_hid); 639 if (acpi_has_method(dev->handle, "_STA")) 640 device_remove_file(&dev->dev, &dev_attr_status); 641 if (dev->handle) 642 device_remove_file(&dev->dev, &dev_attr_path); 643 } 644