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 /** 30 * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent 31 * @acpi_dev: ACPI device object. 32 * @modalias: Buffer to print into. 33 * @size: Size of the buffer. 34 * 35 * Creates hid/cid(s) string needed for modalias and uevent 36 * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get: 37 * char *modalias: "acpi:IBM0001:ACPI0001" 38 * Return: 0: no _HID and no _CID 39 * -EINVAL: output error 40 * -ENOMEM: output is truncated 41 */ 42 static int create_pnp_modalias(struct acpi_device *acpi_dev, char *modalias, 43 int size) 44 { 45 int len; 46 int count; 47 struct acpi_hardware_id *id; 48 49 /* 50 * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should 51 * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the 52 * device's list. 53 */ 54 count = 0; 55 list_for_each_entry(id, &acpi_dev->pnp.ids, list) 56 if (strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 57 count++; 58 59 if (!count) 60 return 0; 61 62 len = snprintf(modalias, size, "acpi:"); 63 if (len <= 0) 64 return len; 65 66 size -= len; 67 68 list_for_each_entry(id, &acpi_dev->pnp.ids, list) { 69 if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID)) 70 continue; 71 72 count = snprintf(&modalias[len], size, "%s:", id->id); 73 if (count < 0) 74 return -EINVAL; 75 76 if (count >= size) 77 return -ENOMEM; 78 79 len += count; 80 size -= count; 81 } 82 modalias[len] = '\0'; 83 return len; 84 } 85 86 /** 87 * create_of_modalias - Creates DT compatible string for modalias and uevent 88 * @acpi_dev: ACPI device object. 89 * @modalias: Buffer to print into. 90 * @size: Size of the buffer. 91 * 92 * Expose DT compatible modalias as of:NnameTCcompatible. This function should 93 * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of 94 * ACPI/PNP IDs. 95 */ 96 static int create_of_modalias(struct acpi_device *acpi_dev, char *modalias, 97 int size) 98 { 99 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; 100 const union acpi_object *of_compatible, *obj; 101 int len, count; 102 int i, nval; 103 char *c; 104 105 acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf); 106 /* DT strings are all in lower case */ 107 for (c = buf.pointer; *c != '\0'; c++) 108 *c = tolower(*c); 109 110 len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); 111 ACPI_FREE(buf.pointer); 112 113 if (len <= 0) 114 return len; 115 116 of_compatible = acpi_dev->data.of_compatible; 117 if (of_compatible->type == ACPI_TYPE_PACKAGE) { 118 nval = of_compatible->package.count; 119 obj = of_compatible->package.elements; 120 } else { /* Must be ACPI_TYPE_STRING. */ 121 nval = 1; 122 obj = of_compatible; 123 } 124 for (i = 0; i < nval; i++, obj++) { 125 count = snprintf(&modalias[len], size, "C%s", 126 obj->string.pointer); 127 if (count < 0) 128 return -EINVAL; 129 130 if (count >= size) 131 return -ENOMEM; 132 133 len += count; 134 size -= count; 135 } 136 modalias[len] = '\0'; 137 return len; 138 } 139 140 int __acpi_device_uevent_modalias(struct acpi_device *adev, 141 struct kobj_uevent_env *env) 142 { 143 int len; 144 145 if (!adev) 146 return -ENODEV; 147 148 if (list_empty(&adev->pnp.ids)) 149 return 0; 150 151 if (add_uevent_var(env, "MODALIAS=")) 152 return -ENOMEM; 153 154 len = create_pnp_modalias(adev, &env->buf[env->buflen - 1], 155 sizeof(env->buf) - env->buflen); 156 if (len < 0) 157 return len; 158 159 env->buflen += len; 160 if (!adev->data.of_compatible) 161 return 0; 162 163 if (len > 0 && add_uevent_var(env, "MODALIAS=")) 164 return -ENOMEM; 165 166 len = create_of_modalias(adev, &env->buf[env->buflen - 1], 167 sizeof(env->buf) - env->buflen); 168 if (len < 0) 169 return len; 170 171 env->buflen += len; 172 173 return 0; 174 } 175 176 /** 177 * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices. 178 * 179 * Create the uevent modalias field for ACPI-enumerated devices. 180 * 181 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 182 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 183 */ 184 int acpi_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env) 185 { 186 return __acpi_device_uevent_modalias(acpi_companion_match(dev), env); 187 } 188 EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias); 189 190 static int __acpi_device_modalias(struct acpi_device *adev, char *buf, int size) 191 { 192 int len, count; 193 194 if (!adev) 195 return -ENODEV; 196 197 if (list_empty(&adev->pnp.ids)) 198 return 0; 199 200 len = create_pnp_modalias(adev, buf, size - 1); 201 if (len < 0) { 202 return len; 203 } else if (len > 0) { 204 buf[len++] = '\n'; 205 size -= len; 206 } 207 if (!adev->data.of_compatible) 208 return len; 209 210 count = create_of_modalias(adev, buf + len, size - 1); 211 if (count < 0) { 212 return count; 213 } else if (count > 0) { 214 len += count; 215 buf[len++] = '\n'; 216 } 217 218 return len; 219 } 220 221 /** 222 * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices. 223 * 224 * Create the modalias sysfs attribute for ACPI-enumerated devices. 225 * 226 * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with 227 * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". 228 */ 229 int acpi_device_modalias(struct device *dev, char *buf, int size) 230 { 231 return __acpi_device_modalias(acpi_companion_match(dev), buf, size); 232 } 233 EXPORT_SYMBOL_GPL(acpi_device_modalias); 234 235 static ssize_t 236 acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) { 237 return __acpi_device_modalias(to_acpi_device(dev), buf, 1024); 238 } 239 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL); 240 241 static ssize_t real_power_state_show(struct device *dev, 242 struct device_attribute *attr, char *buf) 243 { 244 struct acpi_device *adev = to_acpi_device(dev); 245 int state; 246 int ret; 247 248 ret = acpi_device_get_power(adev, &state); 249 if (ret) 250 return ret; 251 252 return sprintf(buf, "%s\n", acpi_power_state_string(state)); 253 } 254 255 static DEVICE_ATTR(real_power_state, 0444, real_power_state_show, NULL); 256 257 static ssize_t power_state_show(struct device *dev, 258 struct device_attribute *attr, char *buf) 259 { 260 struct acpi_device *adev = to_acpi_device(dev); 261 262 return sprintf(buf, "%s\n", acpi_power_state_string(adev->power.state)); 263 } 264 265 static DEVICE_ATTR(power_state, 0444, power_state_show, NULL); 266 267 static ssize_t 268 acpi_eject_store(struct device *d, struct device_attribute *attr, 269 const char *buf, size_t count) 270 { 271 struct acpi_device *acpi_device = to_acpi_device(d); 272 acpi_object_type not_used; 273 acpi_status status; 274 275 if (!count || buf[0] != '1') 276 return -EINVAL; 277 278 if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) 279 && !acpi_device->driver) 280 return -ENODEV; 281 282 status = acpi_get_type(acpi_device->handle, ¬_used); 283 if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) 284 return -ENODEV; 285 286 get_device(&acpi_device->dev); 287 status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT); 288 if (ACPI_SUCCESS(status)) 289 return count; 290 291 put_device(&acpi_device->dev); 292 acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT, 293 ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL); 294 return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; 295 } 296 297 static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store); 298 299 static ssize_t 300 acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) { 301 struct acpi_device *acpi_dev = to_acpi_device(dev); 302 303 return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev)); 304 } 305 static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL); 306 307 static ssize_t acpi_device_uid_show(struct device *dev, 308 struct device_attribute *attr, char *buf) 309 { 310 struct acpi_device *acpi_dev = to_acpi_device(dev); 311 312 return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id); 313 } 314 static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL); 315 316 static ssize_t acpi_device_adr_show(struct device *dev, 317 struct device_attribute *attr, char *buf) 318 { 319 struct acpi_device *acpi_dev = to_acpi_device(dev); 320 321 return sprintf(buf, "0x%08x\n", 322 (unsigned int)(acpi_dev->pnp.bus_address)); 323 } 324 static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL); 325 326 static ssize_t 327 acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) { 328 struct acpi_device *acpi_dev = to_acpi_device(dev); 329 struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL}; 330 int result; 331 332 result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path); 333 if (result) 334 goto end; 335 336 result = sprintf(buf, "%s\n", (char*)path.pointer); 337 kfree(path.pointer); 338 end: 339 return result; 340 } 341 static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL); 342 343 /* sysfs file that shows description text from the ACPI _STR method */ 344 static ssize_t description_show(struct device *dev, 345 struct device_attribute *attr, 346 char *buf) { 347 struct acpi_device *acpi_dev = to_acpi_device(dev); 348 int result; 349 350 if (acpi_dev->pnp.str_obj == NULL) 351 return 0; 352 353 /* 354 * The _STR object contains a Unicode identifier for a device. 355 * We need to convert to utf-8 so it can be displayed. 356 */ 357 result = utf16s_to_utf8s( 358 (wchar_t *)acpi_dev->pnp.str_obj->buffer.pointer, 359 acpi_dev->pnp.str_obj->buffer.length, 360 UTF16_LITTLE_ENDIAN, buf, 361 PAGE_SIZE); 362 363 buf[result++] = '\n'; 364 365 return result; 366 } 367 static DEVICE_ATTR(description, 0444, description_show, NULL); 368 369 static ssize_t 370 acpi_device_sun_show(struct device *dev, struct device_attribute *attr, 371 char *buf) { 372 struct acpi_device *acpi_dev = to_acpi_device(dev); 373 acpi_status status; 374 unsigned long long sun; 375 376 status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun); 377 if (ACPI_FAILURE(status)) 378 return -ENODEV; 379 380 return sprintf(buf, "%llu\n", sun); 381 } 382 static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL); 383 384 static ssize_t status_show(struct device *dev, struct device_attribute *attr, 385 char *buf) { 386 struct acpi_device *acpi_dev = to_acpi_device(dev); 387 acpi_status status; 388 unsigned long long sta; 389 390 status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta); 391 if (ACPI_FAILURE(status)) 392 return -ENODEV; 393 394 return sprintf(buf, "%llu\n", sta); 395 } 396 static DEVICE_ATTR_RO(status); 397 398 /** 399 * acpi_device_setup_files - Create sysfs attributes of an ACPI device. 400 * @dev: ACPI device object. 401 */ 402 int acpi_device_setup_files(struct acpi_device *dev) 403 { 404 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 405 acpi_status status; 406 int result = 0; 407 408 /* 409 * Devices gotten from FADT don't have a "path" attribute 410 */ 411 if (dev->handle) { 412 result = device_create_file(&dev->dev, &dev_attr_path); 413 if (result) 414 goto end; 415 } 416 417 if (!list_empty(&dev->pnp.ids)) { 418 result = device_create_file(&dev->dev, &dev_attr_hid); 419 if (result) 420 goto end; 421 422 result = device_create_file(&dev->dev, &dev_attr_modalias); 423 if (result) 424 goto end; 425 } 426 427 /* 428 * If device has _STR, 'description' file is created 429 */ 430 if (acpi_has_method(dev->handle, "_STR")) { 431 status = acpi_evaluate_object(dev->handle, "_STR", 432 NULL, &buffer); 433 if (ACPI_FAILURE(status)) 434 buffer.pointer = NULL; 435 dev->pnp.str_obj = buffer.pointer; 436 result = device_create_file(&dev->dev, &dev_attr_description); 437 if (result) 438 goto end; 439 } 440 441 if (dev->pnp.type.bus_address) 442 result = device_create_file(&dev->dev, &dev_attr_adr); 443 if (dev->pnp.unique_id) 444 result = device_create_file(&dev->dev, &dev_attr_uid); 445 446 if (acpi_has_method(dev->handle, "_SUN")) { 447 result = device_create_file(&dev->dev, &dev_attr_sun); 448 if (result) 449 goto end; 450 } 451 452 if (acpi_has_method(dev->handle, "_STA")) { 453 result = device_create_file(&dev->dev, &dev_attr_status); 454 if (result) 455 goto end; 456 } 457 458 /* 459 * If device has _EJ0, 'eject' file is created that is used to trigger 460 * hot-removal function from userland. 461 */ 462 if (acpi_has_method(dev->handle, "_EJ0")) { 463 result = device_create_file(&dev->dev, &dev_attr_eject); 464 if (result) 465 return result; 466 } 467 468 if (dev->flags.power_manageable) { 469 result = device_create_file(&dev->dev, &dev_attr_power_state); 470 if (result) 471 return result; 472 473 if (dev->power.flags.power_resources) 474 result = device_create_file(&dev->dev, 475 &dev_attr_real_power_state); 476 } 477 478 end: 479 return result; 480 } 481 482 /** 483 * acpi_device_remove_files - Remove sysfs attributes of an ACPI device. 484 * @dev: ACPI device object. 485 */ 486 void acpi_device_remove_files(struct acpi_device *dev) 487 { 488 if (dev->flags.power_manageable) { 489 device_remove_file(&dev->dev, &dev_attr_power_state); 490 if (dev->power.flags.power_resources) 491 device_remove_file(&dev->dev, 492 &dev_attr_real_power_state); 493 } 494 495 /* 496 * If device has _STR, remove 'description' file 497 */ 498 if (acpi_has_method(dev->handle, "_STR")) { 499 kfree(dev->pnp.str_obj); 500 device_remove_file(&dev->dev, &dev_attr_description); 501 } 502 /* 503 * If device has _EJ0, remove 'eject' file. 504 */ 505 if (acpi_has_method(dev->handle, "_EJ0")) 506 device_remove_file(&dev->dev, &dev_attr_eject); 507 508 if (acpi_has_method(dev->handle, "_SUN")) 509 device_remove_file(&dev->dev, &dev_attr_sun); 510 511 if (dev->pnp.unique_id) 512 device_remove_file(&dev->dev, &dev_attr_uid); 513 if (dev->pnp.type.bus_address) 514 device_remove_file(&dev->dev, &dev_attr_adr); 515 device_remove_file(&dev->dev, &dev_attr_modalias); 516 device_remove_file(&dev->dev, &dev_attr_hid); 517 if (acpi_has_method(dev->handle, "_STA")) 518 device_remove_file(&dev->dev, &dev_attr_status); 519 if (dev->handle) 520 device_remove_file(&dev->dev, &dev_attr_path); 521 } 522