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