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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 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)
304
305define_one_state_ro(name, show_state_name);
306define_one_state_ro(desc, show_state_desc);
307define_one_state_ro(latency, show_state_exit_latency);
308define_one_state_ro(residency, show_state_target_residency);
309define_one_state_ro(power, show_state_power_usage);
310define_one_state_ro(usage, show_state_usage);
311define_one_state_ro(time, show_state_time);
312define_one_state_rw(disable, show_state_disable, store_state_disable);
313
314static struct attribute *cpuidle_state_default_attrs[] = {
315 &attr_name.attr,
316 &attr_desc.attr,
317 &attr_latency.attr,
318 &attr_residency.attr,
319 &attr_power.attr,
320 &attr_usage.attr,
321 &attr_time.attr,
322 &attr_disable.attr,
323 NULL
324};
325
326struct cpuidle_state_kobj {
327 struct cpuidle_state *state;
328 struct cpuidle_state_usage *state_usage;
329 struct completion kobj_unregister;
330 struct kobject kobj;
331};
332
333#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
334#define kobj_to_state(k) (kobj_to_state_obj(k)->state)
335#define kobj_to_state_usage(k) (kobj_to_state_obj(k)->state_usage)
336#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
337
338static ssize_t cpuidle_state_show(struct kobject *kobj, struct attribute *attr,
339 char * buf)
340{
341 int ret = -EIO;
342 struct cpuidle_state *state = kobj_to_state(kobj);
343 struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj);
344 struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
345
346 if (cattr->show)
347 ret = cattr->show(state, state_usage, buf);
348
349 return ret;
350}
351
352static ssize_t cpuidle_state_store(struct kobject *kobj, struct attribute *attr,
353 const char *buf, size_t size)
354{
355 int ret = -EIO;
356 struct cpuidle_state *state = kobj_to_state(kobj);
357 struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj);
358 struct cpuidle_state_attr *cattr = attr_to_stateattr(attr);
359
360 if (cattr->store)
361 ret = cattr->store(state, state_usage, buf, size);
362
363 return ret;
364}
365
366static const struct sysfs_ops cpuidle_state_sysfs_ops = {
367 .show = cpuidle_state_show,
368 .store = cpuidle_state_store,
369};
370
371static void cpuidle_state_sysfs_release(struct kobject *kobj)
372{
373 struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
374
375 complete(&state_obj->kobj_unregister);
376}
377
378static struct kobj_type ktype_state_cpuidle = {
379 .sysfs_ops = &cpuidle_state_sysfs_ops,
380 .default_attrs = cpuidle_state_default_attrs,
381 .release = cpuidle_state_sysfs_release,
382};
383
384static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
385{
386 kobject_put(&device->kobjs[i]->kobj);
387 wait_for_completion(&device->kobjs[i]->kobj_unregister);
388 kfree(device->kobjs[i]);
389 device->kobjs[i] = NULL;
390}
391
392/**
393 * cpuidle_add_state_sysfs - adds cpuidle states sysfs attributes
394 * @device: the target device
395 */
396static int cpuidle_add_state_sysfs(struct cpuidle_device *device)
397{
398 int i, ret = -ENOMEM;
399 struct cpuidle_state_kobj *kobj;
400 struct cpuidle_device_kobj *kdev = device->kobj_dev;
401 struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device);
402
403 /* state statistics */
404 for (i = 0; i < drv->state_count; i++) {
405 kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
406 if (!kobj)
407 goto error_state;
408 kobj->state = &drv->states[i];
409 kobj->state_usage = &device->states_usage[i];
410 init_completion(&kobj->kobj_unregister);
411
412 ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle,
413 &kdev->kobj, "state%d", i);
414 if (ret) {
415 kfree(kobj);
416 goto error_state;
417 }
418 kobject_uevent(&kobj->kobj, KOBJ_ADD);
419 device->kobjs[i] = kobj;
420 }
421
422 return 0;
423
424error_state:
425 for (i = i - 1; i >= 0; i--)
426 cpuidle_free_state_kobj(device, i);
427 return ret;
428}
429
430/**
431 * cpuidle_remove_driver_sysfs - removes the cpuidle states sysfs attributes
432 * @device: the target device
433 */
434static void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
435{
436 struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device);
437 int i;
438
439 for (i = 0; i < drv->state_count; i++)
440 cpuidle_free_state_kobj(device, i);
441}
442
443#ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS
444#define kobj_to_driver_kobj(k) container_of(k, struct cpuidle_driver_kobj, kobj)
445#define attr_to_driver_attr(a) container_of(a, struct cpuidle_driver_attr, attr)
446
447#define define_one_driver_ro(_name, show) \
448 static struct cpuidle_driver_attr attr_driver_##_name = \
449 __ATTR(_name, 0444, show, NULL)
450
451struct cpuidle_driver_kobj {
452 struct cpuidle_driver *drv;
453 struct completion kobj_unregister;
454 struct kobject kobj;
455};
456
457struct cpuidle_driver_attr {
458 struct attribute attr;
459 ssize_t (*show)(struct cpuidle_driver *, char *);
460 ssize_t (*store)(struct cpuidle_driver *, const char *, size_t);
461};
462
463static ssize_t show_driver_name(struct cpuidle_driver *drv, char *buf)
464{
465 ssize_t ret;
466
467 spin_lock(&cpuidle_driver_lock);
468 ret = sprintf(buf, "%s\n", drv ? drv->name : "none");
469 spin_unlock(&cpuidle_driver_lock);
470
471 return ret;
472}
473
474static void cpuidle_driver_sysfs_release(struct kobject *kobj)
475{
476 struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj);
477 complete(&driver_kobj->kobj_unregister);
478}
479
480static ssize_t cpuidle_driver_show(struct kobject *kobj, struct attribute *attr,
481 char *buf)
482{
483 int ret = -EIO;
484 struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj);
485 struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr);
486
487 if (dattr->show)
488 ret = dattr->show(driver_kobj->drv, buf);
489
490 return ret;
491}
492
493static ssize_t cpuidle_driver_store(struct kobject *kobj, struct attribute *attr,
494 const char *buf, size_t size)
495{
496 int ret = -EIO;
497 struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj);
498 struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr);
499
500 if (dattr->store)
501 ret = dattr->store(driver_kobj->drv, buf, size);
502
503 return ret;
504}
505
506define_one_driver_ro(name, show_driver_name);
507
508static const struct sysfs_ops cpuidle_driver_sysfs_ops = {
509 .show = cpuidle_driver_show,
510 .store = cpuidle_driver_store,
511};
512
513static struct attribute *cpuidle_driver_default_attrs[] = {
514 &attr_driver_name.attr,
515 NULL
516};
517
518static struct kobj_type ktype_driver_cpuidle = {
519 .sysfs_ops = &cpuidle_driver_sysfs_ops,
520 .default_attrs = cpuidle_driver_default_attrs,
521 .release = cpuidle_driver_sysfs_release,
522};
523
524/**
525 * cpuidle_add_driver_sysfs - adds the driver name sysfs attribute
526 * @device: the target device
527 */
528static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev)
529{
530 struct cpuidle_driver_kobj *kdrv;
531 struct cpuidle_device_kobj *kdev = dev->kobj_dev;
532 struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
533 int ret;
534
535 kdrv = kzalloc(sizeof(*kdrv), GFP_KERNEL);
536 if (!kdrv)
537 return -ENOMEM;
538
539 kdrv->drv = drv;
540 init_completion(&kdrv->kobj_unregister);
541
542 ret = kobject_init_and_add(&kdrv->kobj, &ktype_driver_cpuidle,
543 &kdev->kobj, "driver");
544 if (ret) {
545 kfree(kdrv);
546 return ret;
547 }
548
549 kobject_uevent(&kdrv->kobj, KOBJ_ADD);
550 dev->kobj_driver = kdrv;
551
552 return ret;
553}
554
555/**
556 * cpuidle_remove_driver_sysfs - removes the driver name sysfs attribute
557 * @device: the target device
558 */
559static void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev)
560{
561 struct cpuidle_driver_kobj *kdrv = dev->kobj_driver;
562 kobject_put(&kdrv->kobj);
563 wait_for_completion(&kdrv->kobj_unregister);
564 kfree(kdrv);
565}
566#else
567static inline int cpuidle_add_driver_sysfs(struct cpuidle_device *dev)
568{
569 return 0;
570}
571
572static inline void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev)
573{
574 ;
575}
576#endif
577
578/**
579 * cpuidle_add_device_sysfs - adds device specific sysfs attributes
580 * @device: the target device
581 */
582int cpuidle_add_device_sysfs(struct cpuidle_device *device)
583{
584 int ret;
585
586 ret = cpuidle_add_state_sysfs(device);
587 if (ret)
588 return ret;
589
590 ret = cpuidle_add_driver_sysfs(device);
591 if (ret)
592 cpuidle_remove_state_sysfs(device);
593 return ret;
594}
595
596/**
597 * cpuidle_remove_device_sysfs : removes device specific sysfs attributes
598 * @device : the target device
599 */
600void cpuidle_remove_device_sysfs(struct cpuidle_device *device)
601{
602 cpuidle_remove_driver_sysfs(device);
603 cpuidle_remove_state_sysfs(device);
604}
605
606/**
607 * cpuidle_add_sysfs - creates a sysfs instance for the target device
608 * @dev: the target device
609 */
610int cpuidle_add_sysfs(struct cpuidle_device *dev)
611{
612 struct cpuidle_device_kobj *kdev;
613 struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu);
614 int error;
615
616 kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
617 if (!kdev)
618 return -ENOMEM;
619 kdev->dev = dev;
620 dev->kobj_dev = kdev;
621
622 init_completion(&kdev->kobj_unregister);
623
624 error = kobject_init_and_add(&kdev->kobj, &ktype_cpuidle, &cpu_dev->kobj,
625 "cpuidle");
626 if (error) {
627 kfree(kdev);
628 return error;
629 }
630
631 kobject_uevent(&kdev->kobj, KOBJ_ADD);
632
633 return 0;
634}
635
636/**
637 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
638 * @dev: the target device
639 */
640void cpuidle_remove_sysfs(struct cpuidle_device *dev)
641{
642 struct cpuidle_device_kobj *kdev = dev->kobj_dev;
643
644 kobject_put(&kdev->kobj);
645 wait_for_completion(&kdev->kobj_unregister);
646 kfree(kdev);
647}
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
15#include "cpuidle.h"
16
17static unsigned int sysfs_switch;
18static int __init cpuidle_sysfs_setup(char *unused)
19{
20 sysfs_switch = 1;
21 return 1;
22}
23__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);
24
25static ssize_t show_available_governors(struct sysdev_class *class,
26 struct sysdev_class_attribute *attr,
27 char *buf)
28{
29 ssize_t i = 0;
30 struct cpuidle_governor *tmp;
31
32 mutex_lock(&cpuidle_lock);
33 list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
34 if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
35 goto out;
36 i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
37 }
38
39out:
40 i+= sprintf(&buf[i], "\n");
41 mutex_unlock(&cpuidle_lock);
42 return i;
43}
44
45static ssize_t show_current_driver(struct sysdev_class *class,
46 struct sysdev_class_attribute *attr,
47 char *buf)
48{
49 ssize_t ret;
50 struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
51
52 spin_lock(&cpuidle_driver_lock);
53 if (cpuidle_driver)
54 ret = sprintf(buf, "%s\n", cpuidle_driver->name);
55 else
56 ret = sprintf(buf, "none\n");
57 spin_unlock(&cpuidle_driver_lock);
58
59 return ret;
60}
61
62static ssize_t show_current_governor(struct sysdev_class *class,
63 struct sysdev_class_attribute *attr,
64 char *buf)
65{
66 ssize_t ret;
67
68 mutex_lock(&cpuidle_lock);
69 if (cpuidle_curr_governor)
70 ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
71 else
72 ret = sprintf(buf, "none\n");
73 mutex_unlock(&cpuidle_lock);
74
75 return ret;
76}
77
78static ssize_t store_current_governor(struct sysdev_class *class,
79 struct sysdev_class_attribute *attr,
80 const char *buf, size_t count)
81{
82 char gov_name[CPUIDLE_NAME_LEN];
83 int ret = -EINVAL;
84 size_t len = count;
85 struct cpuidle_governor *gov;
86
87 if (!len || len >= sizeof(gov_name))
88 return -EINVAL;
89
90 memcpy(gov_name, buf, len);
91 gov_name[len] = '\0';
92 if (gov_name[len - 1] == '\n')
93 gov_name[--len] = '\0';
94
95 mutex_lock(&cpuidle_lock);
96
97 list_for_each_entry(gov, &cpuidle_governors, governor_list) {
98 if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
99 ret = cpuidle_switch_governor(gov);
100 break;
101 }
102 }
103
104 mutex_unlock(&cpuidle_lock);
105
106 if (ret)
107 return ret;
108 else
109 return count;
110}
111
112static SYSDEV_CLASS_ATTR(current_driver, 0444, show_current_driver, NULL);
113static SYSDEV_CLASS_ATTR(current_governor_ro, 0444, show_current_governor,
114 NULL);
115
116static struct attribute *cpuclass_default_attrs[] = {
117 &attr_current_driver.attr,
118 &attr_current_governor_ro.attr,
119 NULL
120};
121
122static SYSDEV_CLASS_ATTR(available_governors, 0444, show_available_governors,
123 NULL);
124static SYSDEV_CLASS_ATTR(current_governor, 0644, show_current_governor,
125 store_current_governor);
126
127static struct attribute *cpuclass_switch_attrs[] = {
128 &attr_available_governors.attr,
129 &attr_current_driver.attr,
130 &attr_current_governor.attr,
131 NULL
132};
133
134static struct attribute_group cpuclass_attr_group = {
135 .attrs = cpuclass_default_attrs,
136 .name = "cpuidle",
137};
138
139/**
140 * cpuidle_add_class_sysfs - add CPU global sysfs attributes
141 */
142int cpuidle_add_class_sysfs(struct sysdev_class *cls)
143{
144 if (sysfs_switch)
145 cpuclass_attr_group.attrs = cpuclass_switch_attrs;
146
147 return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
148}
149
150/**
151 * cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
152 */
153void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
154{
155 sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group);
156}
157
158struct cpuidle_attr {
159 struct attribute attr;
160 ssize_t (*show)(struct cpuidle_device *, char *);
161 ssize_t (*store)(struct cpuidle_device *, const char *, size_t count);
162};
163
164#define define_one_ro(_name, show) \
165 static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
166#define define_one_rw(_name, show, store) \
167 static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)
168
169#define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
170#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
171static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
172{
173 int ret = -EIO;
174 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
175 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
176
177 if (cattr->show) {
178 mutex_lock(&cpuidle_lock);
179 ret = cattr->show(dev, buf);
180 mutex_unlock(&cpuidle_lock);
181 }
182 return ret;
183}
184
185static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
186 const char * buf, size_t count)
187{
188 int ret = -EIO;
189 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
190 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
191
192 if (cattr->store) {
193 mutex_lock(&cpuidle_lock);
194 ret = cattr->store(dev, buf, count);
195 mutex_unlock(&cpuidle_lock);
196 }
197 return ret;
198}
199
200static const struct sysfs_ops cpuidle_sysfs_ops = {
201 .show = cpuidle_show,
202 .store = cpuidle_store,
203};
204
205static void cpuidle_sysfs_release(struct kobject *kobj)
206{
207 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
208
209 complete(&dev->kobj_unregister);
210}
211
212static struct kobj_type ktype_cpuidle = {
213 .sysfs_ops = &cpuidle_sysfs_ops,
214 .release = cpuidle_sysfs_release,
215};
216
217struct cpuidle_state_attr {
218 struct attribute attr;
219 ssize_t (*show)(struct cpuidle_state *, char *);
220 ssize_t (*store)(struct cpuidle_state *, 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_show_state_function(_name) \
227static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
228{ \
229 return sprintf(buf, "%u\n", state->_name);\
230}
231
232#define define_show_state_ull_function(_name) \
233static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
234{ \
235 return sprintf(buf, "%llu\n", state->_name);\
236}
237
238#define define_show_state_str_function(_name) \
239static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
240{ \
241 if (state->_name[0] == '\0')\
242 return sprintf(buf, "<null>\n");\
243 return sprintf(buf, "%s\n", state->_name);\
244}
245
246define_show_state_function(exit_latency)
247define_show_state_function(power_usage)
248define_show_state_ull_function(usage)
249define_show_state_ull_function(time)
250define_show_state_str_function(name)
251define_show_state_str_function(desc)
252
253define_one_state_ro(name, show_state_name);
254define_one_state_ro(desc, show_state_desc);
255define_one_state_ro(latency, show_state_exit_latency);
256define_one_state_ro(power, show_state_power_usage);
257define_one_state_ro(usage, show_state_usage);
258define_one_state_ro(time, show_state_time);
259
260static struct attribute *cpuidle_state_default_attrs[] = {
261 &attr_name.attr,
262 &attr_desc.attr,
263 &attr_latency.attr,
264 &attr_power.attr,
265 &attr_usage.attr,
266 &attr_time.attr,
267 NULL
268};
269
270#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
271#define kobj_to_state(k) (kobj_to_state_obj(k)->state)
272#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
273static ssize_t cpuidle_state_show(struct kobject * kobj,
274 struct attribute * attr ,char * buf)
275{
276 int ret = -EIO;
277 struct cpuidle_state *state = kobj_to_state(kobj);
278 struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
279
280 if (cattr->show)
281 ret = cattr->show(state, buf);
282
283 return ret;
284}
285
286static const struct sysfs_ops cpuidle_state_sysfs_ops = {
287 .show = cpuidle_state_show,
288};
289
290static void cpuidle_state_sysfs_release(struct kobject *kobj)
291{
292 struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
293
294 complete(&state_obj->kobj_unregister);
295}
296
297static struct kobj_type ktype_state_cpuidle = {
298 .sysfs_ops = &cpuidle_state_sysfs_ops,
299 .default_attrs = cpuidle_state_default_attrs,
300 .release = cpuidle_state_sysfs_release,
301};
302
303static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
304{
305 kobject_put(&device->kobjs[i]->kobj);
306 wait_for_completion(&device->kobjs[i]->kobj_unregister);
307 kfree(device->kobjs[i]);
308 device->kobjs[i] = NULL;
309}
310
311/**
312 * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
313 * @device: the target device
314 */
315int cpuidle_add_state_sysfs(struct cpuidle_device *device)
316{
317 int i, ret = -ENOMEM;
318 struct cpuidle_state_kobj *kobj;
319
320 /* state statistics */
321 for (i = 0; i < device->state_count; i++) {
322 kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
323 if (!kobj)
324 goto error_state;
325 kobj->state = &device->states[i];
326 init_completion(&kobj->kobj_unregister);
327
328 ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj,
329 "state%d", i);
330 if (ret) {
331 kfree(kobj);
332 goto error_state;
333 }
334 kobject_uevent(&kobj->kobj, KOBJ_ADD);
335 device->kobjs[i] = kobj;
336 }
337
338 return 0;
339
340error_state:
341 for (i = i - 1; i >= 0; i--)
342 cpuidle_free_state_kobj(device, i);
343 return ret;
344}
345
346/**
347 * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
348 * @device: the target device
349 */
350void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
351{
352 int i;
353
354 for (i = 0; i < device->state_count; i++)
355 cpuidle_free_state_kobj(device, i);
356}
357
358/**
359 * cpuidle_add_sysfs - creates a sysfs instance for the target device
360 * @sysdev: the target device
361 */
362int cpuidle_add_sysfs(struct sys_device *sysdev)
363{
364 int cpu = sysdev->id;
365 struct cpuidle_device *dev;
366 int error;
367
368 dev = per_cpu(cpuidle_devices, cpu);
369 error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj,
370 "cpuidle");
371 if (!error)
372 kobject_uevent(&dev->kobj, KOBJ_ADD);
373 return error;
374}
375
376/**
377 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
378 * @sysdev: the target device
379 */
380void cpuidle_remove_sysfs(struct sys_device *sysdev)
381{
382 int cpu = sysdev->id;
383 struct cpuidle_device *dev;
384
385 dev = per_cpu(cpuidle_devices, cpu);
386 kobject_put(&dev->kobj);
387}