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