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 /* Avoid unnecessarily loading modules for non present devices. */ 150 if (!acpi_device_is_present(acpi_dev)) 151 return 0; 152 153 /* 154 * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should 155 * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the 156 * device's list. 157 */ 158 count = 0; 159 list_for_each_entry(id, &acpi_dev->pnp.ids, list) 160 if (strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 161 count++; 162 163 if (!count) 164 return 0; 165 166 len = snprintf(modalias, size, "acpi:"); 167 if (len <= 0) 168 return len; 169 170 size -= len; 171 172 list_for_each_entry(id, &acpi_dev->pnp.ids, list) { 173 if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 174 continue; 175 176 count = snprintf(&modalias[len], size, "%s:", id->id); 177 if (count < 0) 178 return -EINVAL; 179 180 if (count >= size) 181 return -ENOMEM; 182 183 len += count; 184 size -= count; 185 } 186 modalias[len] = '\0'; 187 return len; 188 } 189 190 /** 191 * create_of_modalias - Creates DT compatible string for modalias and uevent 192 * @acpi_dev: ACPI device object. 193 * @modalias: Buffer to print into. 194 * @size: Size of the buffer. 195 * 196 * Expose DT compatible modalias as of:NnameTCcompatible. This function should 197 * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of 198 * ACPI/PNP IDs. 199 */ 200 static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias, 201 int size) 202 { 203 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; 204 const union acpi_object *of_compatible, *obj; 205 acpi_status status; 206 int len, count; 207 int i, nval; 208 char *c; 209 210 status = acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf); 211 if (ACPI_FAILURE(status)) 212 return -ENODEV; 213 214 /* DT strings are all in lower case */ 215 for (c = buf.pointer; *c != '\0'; c++) 216 *c = tolower(*c); 217 218 len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); 219 ACPI_FREE(buf.pointer); 220 221 if (len <= 0) 222 return len; 223 224 of_compatible = acpi_dev->data.of_compatible; 225 if (of_compatible->type == ACPI_TYPE_PACKAGE) { 226 nval = of_compatible->package.count; 227 obj = of_compatible->package.elements; 228 } else { /* Must be ACPI_TYPE_STRING. */ 229 nval = 1; 230 obj = of_compatible; 231 } 232 for (i = 0; i < nval; i++, obj++) { 233 count = snprintf(&modalias[len], size, "C%s", 234 obj->string.pointer); 235 if (count < 0) 236 return -EINVAL; 237 238 if (count >= size) 239 return -ENOMEM; 240 241 len += count; 242 size -= count; 243 } 244 modalias[len] = '\0'; 245 return len; 246 } 247 248 int __acpi_device_uevent_modalias(struct acpi_device *adev, 249 struct kobj_uevent_env *env) 250 { 251 int len; 252 253 if (!adev) 254 return -ENODEV; 255 256 if (list_empty(&adev->pnp.ids)) 257 return 0; 258 259 if (add_uevent_var(env, "MODALIAS=")) 260 return -ENOMEM; 261 262 len = create_pnp_modalias(adev, &env->buf[env->buflen - 1], 263 sizeof(env->buf) - env->buflen); 264 if (len < 0) 265 return len; 266 267 env->buflen += len; 268 if (!adev->data.of_compatible) 269 return 0; 270 271 if (len > 0 && add_uevent_var(env, "MODALIAS=")) 272 return -ENOMEM; 273 274 len = create_of_modalias(adev, &env->buf[env->buflen - 1], 275 sizeof(env->buf) - env->buflen); 276 if (len < 0) 277 return len; 278 279 env->buflen += len; 280 281 return 0; 282 } 283 284 /** 285 * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices. 286 * 287 * Create the uevent modalias field for ACPI-enumerated devices. 288 * 289 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 290 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 291 */ 292 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) 293 { 294 return __acpi_device_uevent_modalias(acpi_companion_match(dev), env); 295 } 296 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias); 297 298 static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size) 299 { 300 int len, count; 301 302 if (!adev) 303 return -ENODEV; 304 305 if (list_empty(&adev->pnp.ids)) 306 return 0; 307 308 len = create_pnp_modalias(adev, buf, size - 1); 309 if (len < 0) { 310 return len; 311 } else if (len > 0) { 312 buf[len++] = '\n'; 313 size -= len; 314 } 315 if (!adev->data.of_compatible) 316 return len; 317 318 count = create_of_modalias(adev, buf + len, size - 1); 319 if (count < 0) { 320 return count; 321 } else if (count > 0) { 322 len += count; 323 buf[len++] = '\n'; 324 } 325 326 return len; 327 } 328 329 /** 330 * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices. 331 * 332 * Create the modalias sysfs attribute for ACPI-enumerated devices. 333 * 334 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 335 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 336 */ 337 int acpi_device_modalias(struct device *dev, char *buf, int size) 338 { 339 return __acpi_device_modalias(acpi_companion_match(dev), buf, size); 340 } 341 EXPORT_SYMBOL_GPL(acpi_device_modalias); 342 343 static ssize_t 344 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) 345 { 346 return __acpi_device_modalias(to_acpi_device(dev), buf, 1024); 347 } 348 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL); 349 350 static ssize_t real_power_state_show(struct device *dev, 351 struct device_attribute *attr, char *buf) 352 { 353 struct acpi_device *adev = to_acpi_device(dev); 354 int state; 355 int ret; 356 357 ret = acpi_device_get_power(adev, &state); 358 if (ret) 359 return ret; 360 361 return sprintf(buf, "%s\n", acpi_power_state_string(state)); 362 } 363 364 static DEVICE_ATTR_RO(real_power_state); 365 366 static ssize_t power_state_show(struct device *dev, 367 struct device_attribute *attr, char *buf) 368 { 369 struct acpi_device *adev = to_acpi_device(dev); 370 371 return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state)); 372 } 373 374 static DEVICE_ATTR_RO(power_state); 375 376 static ssize_t 377 acpi_eject_store(struct device *d, struct device_attribute *attr, 378 const char *buf, size_t count) 379 { 380 struct acpi_device *acpi_device = to_acpi_device(d); 381 acpi_object_type not_used; 382 acpi_status status; 383 384 if (!count || buf[0] != '1') 385 return -EINVAL; 386 387 if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) 388 && !acpi_device->driver) 389 return -ENODEV; 390 391 status = acpi_get_type(acpi_device->handle, ¬_used); 392 if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) 393 return -ENODEV; 394 395 get_device(&acpi_device->dev); 396 status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT); 397 if (ACPI_SUCCESS(status)) 398 return count; 399 400 put_device(&acpi_device->dev); 401 acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT, 402 ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL); 403 return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; 404 } 405 406 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store); 407 408 static ssize_t 409 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) 410 { 411 struct acpi_device *acpi_dev = to_acpi_device(dev); 412 413 return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev)); 414 } 415 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL); 416 417 static ssize_t acpi_device_uid_show(struct device *dev, 418 struct device_attribute *attr, char *buf) 419 { 420 struct acpi_device *acpi_dev = to_acpi_device(dev); 421 422 return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id); 423 } 424 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL); 425 426 static ssize_t acpi_device_adr_show(struct device *dev, 427 struct device_attribute *attr, char *buf) 428 { 429 struct acpi_device *acpi_dev = to_acpi_device(dev); 430 431 if (acpi_dev->pnp.bus_address > U32_MAX) 432 return sprintf(buf, "0x%016llx\n", acpi_dev->pnp.bus_address); 433 else 434 return sprintf(buf, "0x%08llx\n", acpi_dev->pnp.bus_address); 435 } 436 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL); 437 438 static ssize_t acpi_device_path_show(struct device *dev, 439 struct device_attribute *attr, char *buf) 440 { 441 struct acpi_device *acpi_dev = to_acpi_device(dev); 442 443 return acpi_object_path(acpi_dev->handle, buf); 444 } 445 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL); 446 447 /* sysfs file that shows description text from the ACPI _STR method */ 448 static ssize_t description_show(struct device *dev, 449 struct device_attribute *attr, 450 char *buf) { 451 struct acpi_device *acpi_dev = to_acpi_device(dev); 452 int result; 453 454 if (acpi_dev->pnp.str_obj == NULL) 455 return 0; 456 457 /* 458 * The _STR object contains a Unicode identifier for a device. 459 * We need to convert to utf-8 so it can be displayed. 460 */ 461 result = utf16s_to_utf8s( 462 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer, 463 acpi_dev->pnp.str_obj->buffer.length, 464 UTF16_LITTLE_ENDIAN, buf, 465 PAGE_SIZE); 466 467 buf[result++] = '\n'; 468 469 return result; 470 } 471 static DEVICE_ATTR_RO(description); 472 473 static ssize_t 474 acpi_device_sun_show(struct device *dev, struct device_attribute *attr, 475 char *buf) { 476 struct acpi_device *acpi_dev = to_acpi_device(dev); 477 acpi_status status; 478 unsigned long long sun; 479 480 status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun); 481 if (ACPI_FAILURE(status)) 482 return -EIO; 483 484 return sprintf(buf, "%llu\n", sun); 485 } 486 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL); 487 488 static ssize_t 489 acpi_device_hrv_show(struct device *dev, struct device_attribute *attr, 490 char *buf) { 491 struct acpi_device *acpi_dev = to_acpi_device(dev); 492 acpi_status status; 493 unsigned long long hrv; 494 495 status = acpi_evaluate_integer(acpi_dev->handle, "_HRV", NULL, &hrv); 496 if (ACPI_FAILURE(status)) 497 return -EIO; 498 499 return sprintf(buf, "%llu\n", hrv); 500 } 501 static DEVICE_ATTR(hrv, 0444, acpi_device_hrv_show, NULL); 502 503 static ssize_t status_show(struct device *dev, struct device_attribute *attr, 504 char *buf) { 505 struct acpi_device *acpi_dev = to_acpi_device(dev); 506 acpi_status status; 507 unsigned long long sta; 508 509 status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta); 510 if (ACPI_FAILURE(status)) 511 return -EIO; 512 513 return sprintf(buf, "%llu\n", sta); 514 } 515 static DEVICE_ATTR_RO(status); 516 517 /** 518 * acpi_device_setup_files - Create sysfs attributes of an ACPI device. 519 * @dev: ACPI device object. 520 */ 521 int acpi_device_setup_files(struct acpi_device *dev) 522 { 523 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 524 acpi_status status; 525 int result = 0; 526 527 /* 528 * Devices gotten from FADT don't have a "path" attribute 529 */ 530 if (dev->handle) { 531 result = device_create_file(&dev->dev, &dev_attr_path); 532 if (result) 533 goto end; 534 } 535 536 if (!list_empty(&dev->pnp.ids)) { 537 result = device_create_file(&dev->dev, &dev_attr_hid); 538 if (result) 539 goto end; 540 541 result = device_create_file(&dev->dev, &dev_attr_modalias); 542 if (result) 543 goto end; 544 } 545 546 /* 547 * If device has _STR, 'description' file is created 548 */ 549 if (acpi_has_method(dev->handle, "_STR")) { 550 status = acpi_evaluate_object(dev->handle, "_STR", 551 NULL, &buffer); 552 if (ACPI_FAILURE(status)) 553 buffer.pointer = NULL; 554 dev->pnp.str_obj = buffer.pointer; 555 result = device_create_file(&dev->dev, &dev_attr_description); 556 if (result) 557 goto end; 558 } 559 560 if (dev->pnp.type.bus_address) 561 result = device_create_file(&dev->dev, &dev_attr_adr); 562 if (dev->pnp.unique_id) 563 result = device_create_file(&dev->dev, &dev_attr_uid); 564 565 if (acpi_has_method(dev->handle, "_SUN")) { 566 result = device_create_file(&dev->dev, &dev_attr_sun); 567 if (result) 568 goto end; 569 } 570 571 if (acpi_has_method(dev->handle, "_HRV")) { 572 result = device_create_file(&dev->dev, &dev_attr_hrv); 573 if (result) 574 goto end; 575 } 576 577 if (acpi_has_method(dev->handle, "_STA")) { 578 result = device_create_file(&dev->dev, &dev_attr_status); 579 if (result) 580 goto end; 581 } 582 583 /* 584 * If device has _EJ0, 'eject' file is created that is used to trigger 585 * hot-removal function from userland. 586 */ 587 if (acpi_has_method(dev->handle, "_EJ0")) { 588 result = device_create_file(&dev->dev, &dev_attr_eject); 589 if (result) 590 return result; 591 } 592 593 if (dev->flags.power_manageable) { 594 result = device_create_file(&dev->dev, &dev_attr_power_state); 595 if (result) 596 return result; 597 598 if (dev->power.flags.power_resources) 599 result = device_create_file(&dev->dev, 600 &dev_attr_real_power_state); 601 } 602 603 acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data); 604 605 end: 606 return result; 607 } 608 609 /** 610 * acpi_device_remove_files - Remove sysfs attributes of an ACPI device. 611 * @dev: ACPI device object. 612 */ 613 void acpi_device_remove_files(struct acpi_device *dev) 614 { 615 acpi_hide_nondev_subnodes(&dev->data); 616 617 if (dev->flags.power_manageable) { 618 device_remove_file(&dev->dev, &dev_attr_power_state); 619 if (dev->power.flags.power_resources) 620 device_remove_file(&dev->dev, 621 &dev_attr_real_power_state); 622 } 623 624 /* 625 * If device has _STR, remove 'description' file 626 */ 627 if (acpi_has_method(dev->handle, "_STR")) { 628 kfree(dev->pnp.str_obj); 629 device_remove_file(&dev->dev, &dev_attr_description); 630 } 631 /* 632 * If device has _EJ0, remove 'eject' file. 633 */ 634 if (acpi_has_method(dev->handle, "_EJ0")) 635 device_remove_file(&dev->dev, &dev_attr_eject); 636 637 if (acpi_has_method(dev->handle, "_SUN")) 638 device_remove_file(&dev->dev, &dev_attr_sun); 639 640 if (acpi_has_method(dev->handle, "_HRV")) 641 device_remove_file(&dev->dev, &dev_attr_hrv); 642 643 if (dev->pnp.unique_id) 644 device_remove_file(&dev->dev, &dev_attr_uid); 645 if (dev->pnp.type.bus_address) 646 device_remove_file(&dev->dev, &dev_attr_adr); 647 device_remove_file(&dev->dev, &dev_attr_modalias); 648 device_remove_file(&dev->dev, &dev_attr_hid); 649 if (acpi_has_method(dev->handle, "_STA")) 650 device_remove_file(&dev->dev, &dev_attr_status); 651 if (dev->handle) 652 device_remove_file(&dev->dev, &dev_attr_path); 653 } 654