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