1 /* 2 * sysfs.c - sysfs support 3 * 4 * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com> 5 * 6 * This code is licenced under the GPL. 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/cpuidle.h> 11 #include <linux/sysfs.h> 12 #include <linux/slab.h> 13 #include <linux/cpu.h> 14 #include <linux/completion.h> 15 #include <linux/capability.h> 16 #include <linux/device.h> 17 #include <linux/kobject.h> 18 19 #include "cpuidle.h" 20 21 static ssize_t show_available_governors(struct device *dev, 22 struct device_attribute *attr, 23 char *buf) 24 { 25 ssize_t i = 0; 26 struct cpuidle_governor *tmp; 27 28 mutex_lock(&cpuidle_lock); 29 list_for_each_entry(tmp, &cpuidle_governors, governor_list) { 30 if (i >= (ssize_t) (PAGE_SIZE - (CPUIDLE_NAME_LEN + 2))) 31 goto out; 32 33 i += scnprintf(&buf[i], CPUIDLE_NAME_LEN + 1, "%s ", tmp->name); 34 } 35 36 out: 37 i+= sprintf(&buf[i], "\n"); 38 mutex_unlock(&cpuidle_lock); 39 return i; 40 } 41 42 static ssize_t show_current_driver(struct device *dev, 43 struct device_attribute *attr, 44 char *buf) 45 { 46 ssize_t ret; 47 struct cpuidle_driver *drv; 48 49 spin_lock(&cpuidle_driver_lock); 50 drv = cpuidle_get_driver(); 51 if (drv) 52 ret = sprintf(buf, "%s\n", drv->name); 53 else 54 ret = sprintf(buf, "none\n"); 55 spin_unlock(&cpuidle_driver_lock); 56 57 return ret; 58 } 59 60 static ssize_t show_current_governor(struct device *dev, 61 struct device_attribute *attr, 62 char *buf) 63 { 64 ssize_t ret; 65 66 mutex_lock(&cpuidle_lock); 67 if (cpuidle_curr_governor) 68 ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name); 69 else 70 ret = sprintf(buf, "none\n"); 71 mutex_unlock(&cpuidle_lock); 72 73 return ret; 74 } 75 76 static ssize_t store_current_governor(struct device *dev, 77 struct device_attribute *attr, 78 const char *buf, size_t count) 79 { 80 char gov_name[CPUIDLE_NAME_LEN + 1]; 81 int ret; 82 struct cpuidle_governor *gov; 83 84 ret = sscanf(buf, "%" __stringify(CPUIDLE_NAME_LEN) "s", gov_name); 85 if (ret != 1) 86 return -EINVAL; 87 88 mutex_lock(&cpuidle_lock); 89 ret = -EINVAL; 90 list_for_each_entry(gov, &cpuidle_governors, governor_list) { 91 if (!strncmp(gov->name, gov_name, CPUIDLE_NAME_LEN)) { 92 ret = cpuidle_switch_governor(gov); 93 break; 94 } 95 } 96 mutex_unlock(&cpuidle_lock); 97 98 return ret ? ret : count; 99 } 100 101 static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL); 102 static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL); 103 static DEVICE_ATTR(current_governor, 0644, show_current_governor, 104 store_current_governor); 105 static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL); 106 107 static struct attribute *cpuidle_attrs[] = { 108 &dev_attr_available_governors.attr, 109 &dev_attr_current_driver.attr, 110 &dev_attr_current_governor.attr, 111 &dev_attr_current_governor_ro.attr, 112 NULL 113 }; 114 115 static struct attribute_group cpuidle_attr_group = { 116 .attrs = cpuidle_attrs, 117 .name = "cpuidle", 118 }; 119 120 /** 121 * cpuidle_add_interface - add CPU global sysfs attributes 122 */ 123 int cpuidle_add_interface(void) 124 { 125 struct device *dev_root = bus_get_dev_root(&cpu_subsys); 126 int retval; 127 128 if (!dev_root) 129 return -EINVAL; 130 131 retval = sysfs_create_group(&dev_root->kobj, &cpuidle_attr_group); 132 put_device(dev_root); 133 return retval; 134 } 135 136 /** 137 * cpuidle_remove_interface - remove CPU global sysfs attributes 138 * @dev: the target device 139 */ 140 void cpuidle_remove_interface(struct device *dev) 141 { 142 sysfs_remove_group(&dev->kobj, &cpuidle_attr_group); 143 } 144 145 struct cpuidle_attr { 146 struct attribute attr; 147 ssize_t (*show)(struct cpuidle_device *, char *); 148 ssize_t (*store)(struct cpuidle_device *, const char *, size_t count); 149 }; 150 151 #define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr) 152 153 struct cpuidle_device_kobj { 154 struct cpuidle_device *dev; 155 struct completion kobj_unregister; 156 struct kobject kobj; 157 }; 158 159 static inline struct cpuidle_device *to_cpuidle_device(struct kobject *kobj) 160 { 161 struct cpuidle_device_kobj *kdev = 162 container_of(kobj, struct cpuidle_device_kobj, kobj); 163 164 return kdev->dev; 165 } 166 167 static ssize_t cpuidle_show(struct kobject *kobj, struct attribute *attr, 168 char *buf) 169 { 170 int ret = -EIO; 171 struct cpuidle_device *dev = to_cpuidle_device(kobj); 172 struct cpuidle_attr *cattr = attr_to_cpuidleattr(attr); 173 174 if (cattr->show) { 175 mutex_lock(&cpuidle_lock); 176 ret = cattr->show(dev, buf); 177 mutex_unlock(&cpuidle_lock); 178 } 179 return ret; 180 } 181 182 static ssize_t cpuidle_store(struct kobject *kobj, struct attribute *attr, 183 const char *buf, size_t count) 184 { 185 int ret = -EIO; 186 struct cpuidle_device *dev = to_cpuidle_device(kobj); 187 struct cpuidle_attr *cattr = attr_to_cpuidleattr(attr); 188 189 if (cattr->store) { 190 mutex_lock(&cpuidle_lock); 191 ret = cattr->store(dev, buf, count); 192 mutex_unlock(&cpuidle_lock); 193 } 194 return ret; 195 } 196 197 static const struct sysfs_ops cpuidle_sysfs_ops = { 198 .show = cpuidle_show, 199 .store = cpuidle_store, 200 }; 201 202 static void cpuidle_sysfs_release(struct kobject *kobj) 203 { 204 struct cpuidle_device_kobj *kdev = 205 container_of(kobj, struct cpuidle_device_kobj, kobj); 206 207 complete(&kdev->kobj_unregister); 208 } 209 210 static const struct kobj_type ktype_cpuidle = { 211 .sysfs_ops = &cpuidle_sysfs_ops, 212 .release = cpuidle_sysfs_release, 213 }; 214 215 struct cpuidle_state_attr { 216 struct attribute attr; 217 ssize_t (*show)(struct cpuidle_state *, \ 218 struct cpuidle_state_usage *, char *); 219 ssize_t (*store)(struct cpuidle_state *, \ 220 struct cpuidle_state_usage *, const char *, size_t); 221 }; 222 223 #define define_one_state_ro(_name, show) \ 224 static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL) 225 226 #define define_one_state_rw(_name, show, store) \ 227 static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0644, show, store) 228 229 #define define_show_state_function(_name) \ 230 static ssize_t show_state_##_name(struct cpuidle_state *state, \ 231 struct cpuidle_state_usage *state_usage, char *buf) \ 232 { \ 233 return sprintf(buf, "%u\n", state->_name);\ 234 } 235 236 #define define_show_state_ull_function(_name) \ 237 static ssize_t show_state_##_name(struct cpuidle_state *state, \ 238 struct cpuidle_state_usage *state_usage, \ 239 char *buf) \ 240 { \ 241 return sprintf(buf, "%llu\n", state_usage->_name);\ 242 } 243 244 #define define_show_state_str_function(_name) \ 245 static ssize_t show_state_##_name(struct cpuidle_state *state, \ 246 struct cpuidle_state_usage *state_usage, \ 247 char *buf) \ 248 { \ 249 if (state->_name[0] == '\0')\ 250 return sprintf(buf, "<null>\n");\ 251 return sprintf(buf, "%s\n", state->_name);\ 252 } 253 254 #define define_show_state_time_function(_name) \ 255 static ssize_t show_state_##_name(struct cpuidle_state *state, \ 256 struct cpuidle_state_usage *state_usage, \ 257 char *buf) \ 258 { \ 259 return sprintf(buf, "%llu\n", ktime_to_us(state->_name##_ns)); \ 260 } 261 262 define_show_state_time_function(exit_latency) 263 define_show_state_time_function(target_residency) 264 define_show_state_function(power_usage) 265 define_show_state_ull_function(usage) 266 define_show_state_ull_function(rejected) 267 define_show_state_str_function(name) 268 define_show_state_str_function(desc) 269 define_show_state_ull_function(above) 270 define_show_state_ull_function(below) 271 272 static ssize_t show_state_time(struct cpuidle_state *state, 273 struct cpuidle_state_usage *state_usage, 274 char *buf) 275 { 276 return sprintf(buf, "%llu\n", ktime_to_us(state_usage->time_ns)); 277 } 278 279 static ssize_t show_state_disable(struct cpuidle_state *state, 280 struct cpuidle_state_usage *state_usage, 281 char *buf) 282 { 283 return sprintf(buf, "%llu\n", 284 state_usage->disable & CPUIDLE_STATE_DISABLED_BY_USER); 285 } 286 287 static ssize_t store_state_disable(struct cpuidle_state *state, 288 struct cpuidle_state_usage *state_usage, 289 const char *buf, size_t size) 290 { 291 unsigned int value; 292 int err; 293 294 if (!capable(CAP_SYS_ADMIN)) 295 return -EPERM; 296 297 err = kstrtouint(buf, 0, &value); 298 if (err) 299 return err; 300 301 if (value) 302 state_usage->disable |= CPUIDLE_STATE_DISABLED_BY_USER; 303 else 304 state_usage->disable &= ~CPUIDLE_STATE_DISABLED_BY_USER; 305 306 return size; 307 } 308 309 static ssize_t show_state_default_status(struct cpuidle_state *state, 310 struct cpuidle_state_usage *state_usage, 311 char *buf) 312 { 313 return sprintf(buf, "%s\n", 314 state->flags & CPUIDLE_FLAG_OFF ? "disabled" : "enabled"); 315 } 316 317 define_one_state_ro(name, show_state_name); 318 define_one_state_ro(desc, show_state_desc); 319 define_one_state_ro(latency, show_state_exit_latency); 320 define_one_state_ro(residency, show_state_target_residency); 321 define_one_state_ro(power, show_state_power_usage); 322 define_one_state_ro(usage, show_state_usage); 323 define_one_state_ro(rejected, show_state_rejected); 324 define_one_state_ro(time, show_state_time); 325 define_one_state_rw(disable, show_state_disable, store_state_disable); 326 define_one_state_ro(above, show_state_above); 327 define_one_state_ro(below, show_state_below); 328 define_one_state_ro(default_status, show_state_default_status); 329 330 static struct attribute *cpuidle_state_default_attrs[] = { 331 &attr_name.attr, 332 &attr_desc.attr, 333 &attr_latency.attr, 334 &attr_residency.attr, 335 &attr_power.attr, 336 &attr_usage.attr, 337 &attr_rejected.attr, 338 &attr_time.attr, 339 &attr_disable.attr, 340 &attr_above.attr, 341 &attr_below.attr, 342 &attr_default_status.attr, 343 NULL 344 }; 345 ATTRIBUTE_GROUPS(cpuidle_state_default); 346 347 struct cpuidle_state_kobj { 348 struct cpuidle_state *state; 349 struct cpuidle_state_usage *state_usage; 350 struct completion kobj_unregister; 351 struct kobject kobj; 352 struct cpuidle_device *device; 353 }; 354 355 #ifdef CONFIG_SUSPEND 356 #define define_show_state_s2idle_ull_function(_name) \ 357 static ssize_t show_state_s2idle_##_name(struct cpuidle_state *state, \ 358 struct cpuidle_state_usage *state_usage, \ 359 char *buf) \ 360 { \ 361 return sprintf(buf, "%llu\n", state_usage->s2idle_##_name);\ 362 } 363 364 define_show_state_s2idle_ull_function(usage); 365 define_show_state_s2idle_ull_function(time); 366 367 #define define_one_state_s2idle_ro(_name, show) \ 368 static struct cpuidle_state_attr attr_s2idle_##_name = \ 369 __ATTR(_name, 0444, show, NULL) 370 371 define_one_state_s2idle_ro(usage, show_state_s2idle_usage); 372 define_one_state_s2idle_ro(time, show_state_s2idle_time); 373 374 static struct attribute *cpuidle_state_s2idle_attrs[] = { 375 &attr_s2idle_usage.attr, 376 &attr_s2idle_time.attr, 377 NULL 378 }; 379 380 static const struct attribute_group cpuidle_state_s2idle_group = { 381 .name = "s2idle", 382 .attrs = cpuidle_state_s2idle_attrs, 383 }; 384 385 static void cpuidle_add_s2idle_attr_group(struct cpuidle_state_kobj *kobj) 386 { 387 int ret; 388 389 if (!kobj->state->enter_s2idle) 390 return; 391 392 ret = sysfs_create_group(&kobj->kobj, &cpuidle_state_s2idle_group); 393 if (ret) 394 pr_debug("%s: sysfs attribute group not created\n", __func__); 395 } 396 397 static void cpuidle_remove_s2idle_attr_group(struct cpuidle_state_kobj *kobj) 398 { 399 if (kobj->state->enter_s2idle) 400 sysfs_remove_group(&kobj->kobj, &cpuidle_state_s2idle_group); 401 } 402 #else 403 static inline void cpuidle_add_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { } 404 static inline void cpuidle_remove_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { } 405 #endif /* CONFIG_SUSPEND */ 406 407 #define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj) 408 #define kobj_to_state(k) (kobj_to_state_obj(k)->state) 409 #define kobj_to_state_usage(k) (kobj_to_state_obj(k)->state_usage) 410 #define kobj_to_device(k) (kobj_to_state_obj(k)->device) 411 #define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr) 412 413 static ssize_t cpuidle_state_show(struct kobject *kobj, struct attribute *attr, 414 char *buf) 415 { 416 int ret = -EIO; 417 struct cpuidle_state *state = kobj_to_state(kobj); 418 struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj); 419 struct cpuidle_state_attr *cattr = attr_to_stateattr(attr); 420 421 if (cattr->show) 422 ret = cattr->show(state, state_usage, buf); 423 424 return ret; 425 } 426 427 static ssize_t cpuidle_state_store(struct kobject *kobj, struct attribute *attr, 428 const char *buf, size_t size) 429 { 430 int ret = -EIO; 431 struct cpuidle_state *state = kobj_to_state(kobj); 432 struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj); 433 struct cpuidle_state_attr *cattr = attr_to_stateattr(attr); 434 struct cpuidle_device *dev = kobj_to_device(kobj); 435 436 if (cattr->store) 437 ret = cattr->store(state, state_usage, buf, size); 438 439 /* reset poll time cache */ 440 dev->poll_limit_ns = 0; 441 442 return ret; 443 } 444 445 static const struct sysfs_ops cpuidle_state_sysfs_ops = { 446 .show = cpuidle_state_show, 447 .store = cpuidle_state_store, 448 }; 449 450 static void cpuidle_state_sysfs_release(struct kobject *kobj) 451 { 452 struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj); 453 454 complete(&state_obj->kobj_unregister); 455 } 456 457 static const struct kobj_type ktype_state_cpuidle = { 458 .sysfs_ops = &cpuidle_state_sysfs_ops, 459 .default_groups = cpuidle_state_default_groups, 460 .release = cpuidle_state_sysfs_release, 461 }; 462 463 static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i) 464 { 465 cpuidle_remove_s2idle_attr_group(device->kobjs[i]); 466 kobject_put(&device->kobjs[i]->kobj); 467 wait_for_completion(&device->kobjs[i]->kobj_unregister); 468 kfree(device->kobjs[i]); 469 device->kobjs[i] = NULL; 470 } 471 472 /** 473 * cpuidle_add_state_sysfs - adds cpuidle states sysfs attributes 474 * @device: the target device 475 */ 476 static int cpuidle_add_state_sysfs(struct cpuidle_device *device) 477 { 478 int i, ret = -ENOMEM; 479 struct cpuidle_state_kobj *kobj; 480 struct cpuidle_device_kobj *kdev = device->kobj_dev; 481 struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device); 482 483 /* state statistics */ 484 for (i = 0; i < drv->state_count; i++) { 485 kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL); 486 if (!kobj) { 487 ret = -ENOMEM; 488 goto error_state; 489 } 490 kobj->state = &drv->states[i]; 491 kobj->state_usage = &device->states_usage[i]; 492 kobj->device = device; 493 init_completion(&kobj->kobj_unregister); 494 495 ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, 496 &kdev->kobj, "state%d", i); 497 if (ret) { 498 kobject_put(&kobj->kobj); 499 kfree(kobj); 500 goto error_state; 501 } 502 cpuidle_add_s2idle_attr_group(kobj); 503 kobject_uevent(&kobj->kobj, KOBJ_ADD); 504 device->kobjs[i] = kobj; 505 } 506 507 return 0; 508 509 error_state: 510 for (i = i - 1; i >= 0; i--) 511 cpuidle_free_state_kobj(device, i); 512 return ret; 513 } 514 515 /** 516 * cpuidle_remove_state_sysfs - removes the cpuidle states sysfs attributes 517 * @device: the target device 518 */ 519 static void cpuidle_remove_state_sysfs(struct cpuidle_device *device) 520 { 521 struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device); 522 int i; 523 524 for (i = 0; i < drv->state_count; i++) 525 cpuidle_free_state_kobj(device, i); 526 } 527 528 #ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS 529 #define kobj_to_driver_kobj(k) container_of(k, struct cpuidle_driver_kobj, kobj) 530 #define attr_to_driver_attr(a) container_of(a, struct cpuidle_driver_attr, attr) 531 532 #define define_one_driver_ro(_name, show) \ 533 static struct cpuidle_driver_attr attr_driver_##_name = \ 534 __ATTR(_name, 0444, show, NULL) 535 536 struct cpuidle_driver_kobj { 537 struct cpuidle_driver *drv; 538 struct completion kobj_unregister; 539 struct kobject kobj; 540 }; 541 542 struct cpuidle_driver_attr { 543 struct attribute attr; 544 ssize_t (*show)(struct cpuidle_driver *, char *); 545 ssize_t (*store)(struct cpuidle_driver *, const char *, size_t); 546 }; 547 548 static ssize_t show_driver_name(struct cpuidle_driver *drv, char *buf) 549 { 550 ssize_t ret; 551 552 spin_lock(&cpuidle_driver_lock); 553 ret = sprintf(buf, "%s\n", drv ? drv->name : "none"); 554 spin_unlock(&cpuidle_driver_lock); 555 556 return ret; 557 } 558 559 static void cpuidle_driver_sysfs_release(struct kobject *kobj) 560 { 561 struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); 562 complete(&driver_kobj->kobj_unregister); 563 } 564 565 static ssize_t cpuidle_driver_show(struct kobject *kobj, struct attribute *attr, 566 char *buf) 567 { 568 int ret = -EIO; 569 struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); 570 struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); 571 572 if (dattr->show) 573 ret = dattr->show(driver_kobj->drv, buf); 574 575 return ret; 576 } 577 578 static ssize_t cpuidle_driver_store(struct kobject *kobj, struct attribute *attr, 579 const char *buf, size_t size) 580 { 581 int ret = -EIO; 582 struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); 583 struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); 584 585 if (dattr->store) 586 ret = dattr->store(driver_kobj->drv, buf, size); 587 588 return ret; 589 } 590 591 define_one_driver_ro(name, show_driver_name); 592 593 static const struct sysfs_ops cpuidle_driver_sysfs_ops = { 594 .show = cpuidle_driver_show, 595 .store = cpuidle_driver_store, 596 }; 597 598 static struct attribute *cpuidle_driver_default_attrs[] = { 599 &attr_driver_name.attr, 600 NULL 601 }; 602 ATTRIBUTE_GROUPS(cpuidle_driver_default); 603 604 static const struct kobj_type ktype_driver_cpuidle = { 605 .sysfs_ops = &cpuidle_driver_sysfs_ops, 606 .default_groups = cpuidle_driver_default_groups, 607 .release = cpuidle_driver_sysfs_release, 608 }; 609 610 /** 611 * cpuidle_add_driver_sysfs - adds the driver name sysfs attribute 612 * @dev: the target device 613 */ 614 static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) 615 { 616 struct cpuidle_driver_kobj *kdrv; 617 struct cpuidle_device_kobj *kdev = dev->kobj_dev; 618 struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); 619 int ret; 620 621 kdrv = kzalloc(sizeof(*kdrv), GFP_KERNEL); 622 if (!kdrv) 623 return -ENOMEM; 624 625 kdrv->drv = drv; 626 init_completion(&kdrv->kobj_unregister); 627 628 ret = kobject_init_and_add(&kdrv->kobj, &ktype_driver_cpuidle, 629 &kdev->kobj, "driver"); 630 if (ret) { 631 kobject_put(&kdrv->kobj); 632 kfree(kdrv); 633 return ret; 634 } 635 636 kobject_uevent(&kdrv->kobj, KOBJ_ADD); 637 dev->kobj_driver = kdrv; 638 639 return ret; 640 } 641 642 /** 643 * cpuidle_remove_driver_sysfs - removes the driver name sysfs attribute 644 * @dev: the target device 645 */ 646 static void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) 647 { 648 struct cpuidle_driver_kobj *kdrv = dev->kobj_driver; 649 kobject_put(&kdrv->kobj); 650 wait_for_completion(&kdrv->kobj_unregister); 651 kfree(kdrv); 652 } 653 #else 654 static inline int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) 655 { 656 return 0; 657 } 658 659 static inline void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) 660 { 661 ; 662 } 663 #endif 664 665 /** 666 * cpuidle_add_device_sysfs - adds device specific sysfs attributes 667 * @device: the target device 668 */ 669 int cpuidle_add_device_sysfs(struct cpuidle_device *device) 670 { 671 int ret; 672 673 ret = cpuidle_add_state_sysfs(device); 674 if (ret) 675 return ret; 676 677 ret = cpuidle_add_driver_sysfs(device); 678 if (ret) 679 cpuidle_remove_state_sysfs(device); 680 return ret; 681 } 682 683 /** 684 * cpuidle_remove_device_sysfs : removes device specific sysfs attributes 685 * @device : the target device 686 */ 687 void cpuidle_remove_device_sysfs(struct cpuidle_device *device) 688 { 689 cpuidle_remove_driver_sysfs(device); 690 cpuidle_remove_state_sysfs(device); 691 } 692 693 /** 694 * cpuidle_add_sysfs - creates a sysfs instance for the target device 695 * @dev: the target device 696 */ 697 int cpuidle_add_sysfs(struct cpuidle_device *dev) 698 { 699 struct cpuidle_device_kobj *kdev; 700 struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu); 701 int error; 702 703 /* 704 * Return if cpu_device is not setup for this CPU. 705 * 706 * This could happen if the arch did not set up cpu_device 707 * since this CPU is not in cpu_present mask and the 708 * driver did not send a correct CPU mask during registration. 709 * Without this check we would end up passing bogus 710 * value for &cpu_dev->kobj in kobject_init_and_add() 711 */ 712 if (!cpu_dev) 713 return -ENODEV; 714 715 kdev = kzalloc(sizeof(*kdev), GFP_KERNEL); 716 if (!kdev) 717 return -ENOMEM; 718 kdev->dev = dev; 719 720 init_completion(&kdev->kobj_unregister); 721 722 error = kobject_init_and_add(&kdev->kobj, &ktype_cpuidle, &cpu_dev->kobj, 723 "cpuidle"); 724 if (error) { 725 kobject_put(&kdev->kobj); 726 kfree(kdev); 727 return error; 728 } 729 730 dev->kobj_dev = kdev; 731 kobject_uevent(&kdev->kobj, KOBJ_ADD); 732 733 return 0; 734 } 735 736 /** 737 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device 738 * @dev: the target device 739 */ 740 void cpuidle_remove_sysfs(struct cpuidle_device *dev) 741 { 742 struct cpuidle_device_kobj *kdev = dev->kobj_dev; 743 744 kobject_put(&kdev->kobj); 745 wait_for_completion(&kdev->kobj_unregister); 746 kfree(kdev); 747 } 748