1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * drivers/acpi/device_sysfs.c - ACPI device sysfs attributes and modalias. 4 * 5 * Copyright (C) 2015, Intel Corp. 6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com> 7 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 8 * 9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 10 * 11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 12 */ 13 14#include <linux/acpi.h> 15#include <linux/device.h> 16#include <linux/export.h> 17#include <linux/nls.h> 18 19#include "internal.h" 20 21static ssize_t acpi_object_path(acpi_handle handle, char *buf) 22{ 23 struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL}; 24 int result; 25 26 result = acpi_get_name(handle, ACPI_FULL_PATHNAME, &path); 27 if (result) 28 return result; 29 30 result = sprintf(buf, "%s\n", (char *)path.pointer); 31 kfree(path.pointer); 32 return result; 33} 34 35struct acpi_data_node_attr { 36 struct attribute attr; 37 ssize_t (*show)(struct acpi_data_node *, char *); 38 ssize_t (*store)(struct acpi_data_node *, const char *, size_t count); 39}; 40 41#define DATA_NODE_ATTR(_name) \ 42 static struct acpi_data_node_attr data_node_##_name = \ 43 __ATTR(_name, 0444, data_node_show_##_name, NULL) 44 45static ssize_t data_node_show_path(struct acpi_data_node *dn, char *buf) 46{ 47 return dn->handle ? acpi_object_path(dn->handle, buf) : 0; 48} 49 50DATA_NODE_ATTR(path); 51 52static struct attribute *acpi_data_node_default_attrs[] = { 53 &data_node_path.attr, 54 NULL 55}; 56ATTRIBUTE_GROUPS(acpi_data_node_default); 57 58#define to_data_node(k) container_of(k, struct acpi_data_node, kobj) 59#define to_attr(a) container_of(a, struct acpi_data_node_attr, attr) 60 61static ssize_t acpi_data_node_attr_show(struct kobject *kobj, 62 struct attribute *attr, char *buf) 63{ 64 struct acpi_data_node *dn = to_data_node(kobj); 65 struct acpi_data_node_attr *dn_attr = to_attr(attr); 66 67 return dn_attr->show ? dn_attr->show(dn, buf) : -ENXIO; 68} 69 70static const struct sysfs_ops acpi_data_node_sysfs_ops = { 71 .show = acpi_data_node_attr_show, 72}; 73 74static void acpi_data_node_release(struct kobject *kobj) 75{ 76 struct acpi_data_node *dn = to_data_node(kobj); 77 78 complete(&dn->kobj_done); 79} 80 81static const struct kobj_type acpi_data_node_ktype = { 82 .sysfs_ops = &acpi_data_node_sysfs_ops, 83 .default_groups = acpi_data_node_default_groups, 84 .release = acpi_data_node_release, 85}; 86 87static void acpi_expose_nondev_subnodes(struct kobject *kobj, 88 struct acpi_device_data *data) 89{ 90 struct list_head *list = &data->subnodes; 91 struct acpi_data_node *dn; 92 93 if (list_empty(list)) 94 return; 95 96 list_for_each_entry(dn, list, sibling) { 97 int ret; 98 99 init_completion(&dn->kobj_done); 100 ret = kobject_init_and_add(&dn->kobj, &acpi_data_node_ktype, 101 kobj, "%s", dn->name); 102 if (!ret) 103 acpi_expose_nondev_subnodes(&dn->kobj, &dn->data); 104 else if (dn->handle) 105 acpi_handle_err(dn->handle, "Failed to expose (%d)\n", ret); 106 } 107} 108 109static void acpi_hide_nondev_subnodes(struct acpi_device_data *data) 110{ 111 struct list_head *list = &data->subnodes; 112 struct acpi_data_node *dn; 113 114 if (list_empty(list)) 115 return; 116 117 list_for_each_entry_reverse(dn, list, sibling) { 118 acpi_hide_nondev_subnodes(&dn->data); 119 kobject_put(&dn->kobj); 120 } 121} 122 123/** 124 * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent 125 * @acpi_dev: ACPI device object. 126 * @modalias: Buffer to print into. 127 * @size: Size of the buffer. 128 * 129 * Creates hid/cid(s) string needed for modalias and uevent 130 * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get: 131 * char *modalias: "acpi:IBM0001:ACPI0001" 132 * Return: 0: no _HID and no _CID 133 * -EINVAL: output error 134 * -ENOMEM: output is truncated 135 */ 136static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalias, 137 int size) 138{ 139 int len; 140 int count; 141 struct acpi_hardware_id *id; 142 143 /* Avoid unnecessarily loading modules for non present devices. */ 144 if (!acpi_device_is_present(acpi_dev)) 145 return 0; 146 147 /* 148 * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should 149 * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the 150 * device's list. 151 */ 152 count = 0; 153 list_for_each_entry(id, &acpi_dev->pnp.ids, list) 154 if (strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 155 count++; 156 157 if (!count) 158 return 0; 159 160 len = snprintf(modalias, size, "acpi:"); 161 if (len >= size) 162 return -ENOMEM; 163 164 size -= len; 165 166 list_for_each_entry(id, &acpi_dev->pnp.ids, list) { 167 if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 168 continue; 169 170 count = snprintf(&modalias[len], size, "%s:", id->id); 171 if (count < 0) 172 return -EINVAL; 173 174 if (count >= size) 175 return -ENOMEM; 176 177 len += count; 178 size -= count; 179 } 180 modalias[len] = '\0'; 181 return len; 182} 183 184/** 185 * create_of_modalias - Creates DT compatible string for modalias and uevent 186 * @acpi_dev: ACPI device object. 187 * @modalias: Buffer to print into. 188 * @size: Size of the buffer. 189 * 190 * Expose DT compatible modalias as of:NnameTCcompatible. This function should 191 * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of 192 * ACPI/PNP IDs. 193 */ 194static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias, 195 int size) 196{ 197 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; 198 const union acpi_object *of_compatible, *obj; 199 acpi_status status; 200 int len, count; 201 int i, nval; 202 char *c; 203 204 status = acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf); 205 if (ACPI_FAILURE(status)) 206 return -ENODEV; 207 208 /* DT strings are all in lower case */ 209 for (c = buf.pointer; *c != '\0'; c++) 210 *c = tolower(*c); 211 212 len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); 213 ACPI_FREE(buf.pointer); 214 215 if (len >= size) 216 return -ENOMEM; 217 218 size -= 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 244int __acpi_device_uevent_modalias(const 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 if (adev->data.of_compatible) 259 len = create_of_modalias(adev, &env->buf[env->buflen - 1], 260 sizeof(env->buf) - env->buflen); 261 else 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; 268 269 return 0; 270} 271 272/** 273 * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices. 274 * @dev: Struct device to get ACPI device node. 275 * @env: Environment variables of the kobject uevent. 276 * 277 * Create the uevent modalias field for ACPI-enumerated devices. 278 * 279 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 280 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 281 */ 282int acpi_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env) 283{ 284 return __acpi_device_uevent_modalias(acpi_companion_match(dev), env); 285} 286EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias); 287 288static int __acpi_device_modalias(const struct acpi_device *adev, char *buf, int size) 289{ 290 int len, count; 291 292 if (!adev) 293 return -ENODEV; 294 295 if (list_empty(&adev->pnp.ids)) 296 return 0; 297 298 len = create_pnp_modalias(adev, buf, size - 1); 299 if (len < 0) { 300 return len; 301 } else if (len > 0) { 302 buf[len++] = '\n'; 303 size -= len; 304 } 305 if (!adev->data.of_compatible) 306 return len; 307 308 count = create_of_modalias(adev, buf + len, size - 1); 309 if (count < 0) { 310 return count; 311 } else if (count > 0) { 312 len += count; 313 buf[len++] = '\n'; 314 } 315 316 return len; 317} 318 319/** 320 * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices. 321 * @dev: Struct device to get ACPI device node. 322 * @buf: The buffer to save pnp_modalias and of_modalias. 323 * @size: Size of buffer. 324 * 325 * Create the modalias sysfs attribute for ACPI-enumerated devices. 326 * 327 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 328 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 329 */ 330int acpi_device_modalias(struct device *dev, char *buf, int size) 331{ 332 return __acpi_device_modalias(acpi_companion_match(dev), buf, size); 333} 334EXPORT_SYMBOL_GPL(acpi_device_modalias); 335 336static ssize_t 337modalias_show(struct device *dev, struct device_attribute *attr, char *buf) 338{ 339 return __acpi_device_modalias(to_acpi_device(dev), buf, 1024); 340} 341static DEVICE_ATTR_RO(modalias); 342 343static ssize_t real_power_state_show(struct device *dev, 344 struct device_attribute *attr, char *buf) 345{ 346 struct acpi_device *adev = to_acpi_device(dev); 347 int state; 348 int ret; 349 350 ret = acpi_device_get_power(adev, &state); 351 if (ret) 352 return ret; 353 354 return sprintf(buf, "%s\n", acpi_power_state_string(state)); 355} 356 357static DEVICE_ATTR_RO(real_power_state); 358 359static ssize_t power_state_show(struct device *dev, 360 struct device_attribute *attr, char *buf) 361{ 362 struct acpi_device *adev = to_acpi_device(dev); 363 364 return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state)); 365} 366 367static DEVICE_ATTR_RO(power_state); 368 369static ssize_t 370eject_store(struct device *d, struct device_attribute *attr, 371 const char *buf, size_t count) 372{ 373 struct acpi_device *acpi_device = to_acpi_device(d); 374 acpi_object_type not_used; 375 acpi_status status; 376 377 if (!count || buf[0] != '1') 378 return -EINVAL; 379 380 if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) 381 && !d->driver) 382 return -ENODEV; 383 384 status = acpi_get_type(acpi_device->handle, ¬_used); 385 if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) 386 return -ENODEV; 387 388 acpi_dev_get(acpi_device); 389 status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT); 390 if (ACPI_SUCCESS(status)) 391 return count; 392 393 acpi_dev_put(acpi_device); 394 acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT, 395 ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL); 396 return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; 397} 398 399static DEVICE_ATTR_WO(eject); 400 401static ssize_t 402hid_show(struct device *dev, struct device_attribute *attr, char *buf) 403{ 404 struct acpi_device *acpi_dev = to_acpi_device(dev); 405 406 return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev)); 407} 408static DEVICE_ATTR_RO(hid); 409 410static ssize_t uid_show(struct device *dev, 411 struct device_attribute *attr, char *buf) 412{ 413 struct acpi_device *acpi_dev = to_acpi_device(dev); 414 415 return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id); 416} 417static DEVICE_ATTR_RO(uid); 418 419static ssize_t adr_show(struct device *dev, 420 struct device_attribute *attr, char *buf) 421{ 422 struct acpi_device *acpi_dev = to_acpi_device(dev); 423 424 if (acpi_dev->pnp.bus_address > U32_MAX) 425 return sprintf(buf, "0x%016llx\n", acpi_dev->pnp.bus_address); 426 else 427 return sprintf(buf, "0x%08llx\n", acpi_dev->pnp.bus_address); 428} 429static DEVICE_ATTR_RO(adr); 430 431static ssize_t path_show(struct device *dev, 432 struct device_attribute *attr, char *buf) 433{ 434 struct acpi_device *acpi_dev = to_acpi_device(dev); 435 436 return acpi_object_path(acpi_dev->handle, buf); 437} 438static DEVICE_ATTR_RO(path); 439 440/* sysfs file that shows description text from the ACPI _STR method */ 441static ssize_t description_show(struct device *dev, 442 struct device_attribute *attr, 443 char *buf) 444{ 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 - 1); 460 461 buf[result++] = '\n'; 462 463 return result; 464} 465static DEVICE_ATTR_RO(description); 466 467static ssize_t 468sun_show(struct device *dev, struct device_attribute *attr, 469 char *buf) 470{ 471 struct acpi_device *acpi_dev = to_acpi_device(dev); 472 acpi_status status; 473 unsigned long long sun; 474 475 status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun); 476 if (ACPI_FAILURE(status)) 477 return -EIO; 478 479 return sprintf(buf, "%llu\n", sun); 480} 481static DEVICE_ATTR_RO(sun); 482 483static ssize_t 484hrv_show(struct device *dev, struct device_attribute *attr, 485 char *buf) 486{ 487 struct acpi_device *acpi_dev = to_acpi_device(dev); 488 acpi_status status; 489 unsigned long long hrv; 490 491 status = acpi_evaluate_integer(acpi_dev->handle, "_HRV", NULL, &hrv); 492 if (ACPI_FAILURE(status)) 493 return -EIO; 494 495 return sprintf(buf, "%llu\n", hrv); 496} 497static DEVICE_ATTR_RO(hrv); 498 499static ssize_t status_show(struct device *dev, struct device_attribute *attr, 500 char *buf) 501{ 502 struct acpi_device *acpi_dev = to_acpi_device(dev); 503 acpi_status status; 504 unsigned long long sta; 505 506 status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta); 507 if (ACPI_FAILURE(status)) 508 return -EIO; 509 510 return sprintf(buf, "%llu\n", sta); 511} 512static DEVICE_ATTR_RO(status); 513 514/** 515 * acpi_device_setup_files - Create sysfs attributes of an ACPI device. 516 * @dev: ACPI device object. 517 */ 518int acpi_device_setup_files(struct acpi_device *dev) 519{ 520 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 521 acpi_status status; 522 int result = 0; 523 524 /* 525 * Devices gotten from FADT don't have a "path" attribute 526 */ 527 if (dev->handle) { 528 result = device_create_file(&dev->dev, &dev_attr_path); 529 if (result) 530 goto end; 531 } 532 533 if (!list_empty(&dev->pnp.ids)) { 534 result = device_create_file(&dev->dev, &dev_attr_hid); 535 if (result) 536 goto end; 537 538 result = device_create_file(&dev->dev, &dev_attr_modalias); 539 if (result) 540 goto end; 541 } 542 543 /* 544 * If device has _STR, 'description' file is created 545 */ 546 if (acpi_has_method(dev->handle, "_STR")) { 547 status = acpi_evaluate_object(dev->handle, "_STR", 548 NULL, &buffer); 549 if (ACPI_FAILURE(status)) 550 buffer.pointer = NULL; 551 dev->pnp.str_obj = buffer.pointer; 552 result = device_create_file(&dev->dev, &dev_attr_description); 553 if (result) 554 goto end; 555 } 556 557 if (dev->pnp.type.bus_address) 558 result = device_create_file(&dev->dev, &dev_attr_adr); 559 if (dev->pnp.unique_id) 560 result = device_create_file(&dev->dev, &dev_attr_uid); 561 562 if (acpi_has_method(dev->handle, "_SUN")) { 563 result = device_create_file(&dev->dev, &dev_attr_sun); 564 if (result) 565 goto end; 566 } 567 568 if (acpi_has_method(dev->handle, "_HRV")) { 569 result = device_create_file(&dev->dev, &dev_attr_hrv); 570 if (result) 571 goto end; 572 } 573 574 if (acpi_has_method(dev->handle, "_STA")) { 575 result = device_create_file(&dev->dev, &dev_attr_status); 576 if (result) 577 goto end; 578 } 579 580 /* 581 * If device has _EJ0, 'eject' file is created that is used to trigger 582 * hot-removal function from userland. 583 */ 584 if (acpi_has_method(dev->handle, "_EJ0")) { 585 result = device_create_file(&dev->dev, &dev_attr_eject); 586 if (result) 587 return result; 588 } 589 590 if (dev->flags.power_manageable) { 591 result = device_create_file(&dev->dev, &dev_attr_power_state); 592 if (result) 593 return result; 594 595 if (dev->power.flags.power_resources) 596 result = device_create_file(&dev->dev, 597 &dev_attr_real_power_state); 598 } 599 600 acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data); 601 602end: 603 return result; 604} 605 606/** 607 * acpi_device_remove_files - Remove sysfs attributes of an ACPI device. 608 * @dev: ACPI device object. 609 */ 610void acpi_device_remove_files(struct acpi_device *dev) 611{ 612 acpi_hide_nondev_subnodes(&dev->data); 613 614 if (dev->flags.power_manageable) { 615 device_remove_file(&dev->dev, &dev_attr_power_state); 616 if (dev->power.flags.power_resources) 617 device_remove_file(&dev->dev, 618 &dev_attr_real_power_state); 619 } 620 621 /* 622 * If device has _STR, remove 'description' file 623 */ 624 if (acpi_has_method(dev->handle, "_STR")) { 625 kfree(dev->pnp.str_obj); 626 device_remove_file(&dev->dev, &dev_attr_description); 627 } 628 /* 629 * If device has _EJ0, remove 'eject' file. 630 */ 631 if (acpi_has_method(dev->handle, "_EJ0")) 632 device_remove_file(&dev->dev, &dev_attr_eject); 633 634 if (acpi_has_method(dev->handle, "_SUN")) 635 device_remove_file(&dev->dev, &dev_attr_sun); 636 637 if (acpi_has_method(dev->handle, "_HRV")) 638 device_remove_file(&dev->dev, &dev_attr_hrv); 639 640 if (dev->pnp.unique_id) 641 device_remove_file(&dev->dev, &dev_attr_uid); 642 if (dev->pnp.type.bus_address) 643 device_remove_file(&dev->dev, &dev_attr_adr); 644 device_remove_file(&dev->dev, &dev_attr_modalias); 645 device_remove_file(&dev->dev, &dev_attr_hid); 646 if (acpi_has_method(dev->handle, "_STA")) 647 device_remove_file(&dev->dev, &dev_attr_status); 648 if (dev->handle) 649 device_remove_file(&dev->dev, &dev_attr_path); 650} 651