2 * sysfs.c - sysfs support
4 * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com>
6 * This code is licenced under the GPL.
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/capability.h>
18 static unsigned int sysfs_switch;
19 static int __init cpuidle_sysfs_setup(char *unused)
24 __setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);
26 static ssize_t show_available_governors(struct device *dev,
27 struct device_attribute *attr,
31 struct cpuidle_governor *tmp;
33 mutex_lock(&cpuidle_lock);
34 list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
35 if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
37 i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
41 i+= sprintf(&buf[i], "\n");
42 mutex_unlock(&cpuidle_lock);
46 static ssize_t show_current_driver(struct device *dev,
47 struct device_attribute *attr,
51 struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
53 spin_lock(&cpuidle_driver_lock);
55 ret = sprintf(buf, "%s\n", cpuidle_driver->name);
57 ret = sprintf(buf, "none\n");
58 spin_unlock(&cpuidle_driver_lock);
63 static ssize_t show_current_governor(struct device *dev,
64 struct device_attribute *attr,
69 mutex_lock(&cpuidle_lock);
70 if (cpuidle_curr_governor)
71 ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
73 ret = sprintf(buf, "none\n");
74 mutex_unlock(&cpuidle_lock);
79 static ssize_t store_current_governor(struct device *dev,
80 struct device_attribute *attr,
81 const char *buf, size_t count)
83 char gov_name[CPUIDLE_NAME_LEN];
86 struct cpuidle_governor *gov;
88 if (!len || len >= sizeof(gov_name))
91 memcpy(gov_name, buf, len);
93 if (gov_name[len - 1] == '\n')
94 gov_name[--len] = '\0';
96 mutex_lock(&cpuidle_lock);
98 list_for_each_entry(gov, &cpuidle_governors, governor_list) {
99 if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
100 ret = cpuidle_switch_governor(gov);
105 mutex_unlock(&cpuidle_lock);
113 static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL);
114 static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL);
116 static struct attribute *cpuidle_default_attrs[] = {
117 &dev_attr_current_driver.attr,
118 &dev_attr_current_governor_ro.attr,
122 static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL);
123 static DEVICE_ATTR(current_governor, 0644, show_current_governor,
124 store_current_governor);
126 static struct attribute *cpuidle_switch_attrs[] = {
127 &dev_attr_available_governors.attr,
128 &dev_attr_current_driver.attr,
129 &dev_attr_current_governor.attr,
133 static struct attribute_group cpuidle_attr_group = {
134 .attrs = cpuidle_default_attrs,
139 * cpuidle_add_interface - add CPU global sysfs attributes
141 int cpuidle_add_interface(struct device *dev)
144 cpuidle_attr_group.attrs = cpuidle_switch_attrs;
146 return sysfs_create_group(&dev->kobj, &cpuidle_attr_group);
150 * cpuidle_remove_interface - remove CPU global sysfs attributes
152 void cpuidle_remove_interface(struct device *dev)
154 sysfs_remove_group(&dev->kobj, &cpuidle_attr_group);
157 struct cpuidle_attr {
158 struct attribute attr;
159 ssize_t (*show)(struct cpuidle_device *, char *);
160 ssize_t (*store)(struct cpuidle_device *, const char *, size_t count);
163 #define define_one_ro(_name, show) \
164 static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
165 #define define_one_rw(_name, show, store) \
166 static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)
168 #define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
169 #define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
170 static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
173 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
174 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
177 mutex_lock(&cpuidle_lock);
178 ret = cattr->show(dev, buf);
179 mutex_unlock(&cpuidle_lock);
184 static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
185 const char * buf, size_t count)
188 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
189 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
192 mutex_lock(&cpuidle_lock);
193 ret = cattr->store(dev, buf, count);
194 mutex_unlock(&cpuidle_lock);
199 static const struct sysfs_ops cpuidle_sysfs_ops = {
200 .show = cpuidle_show,
201 .store = cpuidle_store,
204 static void cpuidle_sysfs_release(struct kobject *kobj)
206 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
208 complete(&dev->kobj_unregister);
211 static struct kobj_type ktype_cpuidle = {
212 .sysfs_ops = &cpuidle_sysfs_ops,
213 .release = cpuidle_sysfs_release,
216 struct cpuidle_state_attr {
217 struct attribute attr;
218 ssize_t (*show)(struct cpuidle_state *, \
219 struct cpuidle_state_usage *, char *);
220 ssize_t (*store)(struct cpuidle_state *, const char *, size_t);
223 #define define_one_state_ro(_name, show) \
224 static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
226 #define define_one_state_rw(_name, show, store) \
227 static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0644, show, store)
229 #define define_show_state_function(_name) \
230 static ssize_t show_state_##_name(struct cpuidle_state *state, \
231 struct cpuidle_state_usage *state_usage, char *buf) \
233 return sprintf(buf, "%u\n", state->_name);\
236 #define define_store_state_function(_name) \
237 static ssize_t store_state_##_name(struct cpuidle_state *state, \
238 const char *buf, size_t size) \
242 if (!capable(CAP_SYS_ADMIN)) \
244 err = kstrtol(buf, 0, &value); \
248 state->disable = 1; \
250 state->disable = 0; \
254 #define define_show_state_ull_function(_name) \
255 static ssize_t show_state_##_name(struct cpuidle_state *state, \
256 struct cpuidle_state_usage *state_usage, char *buf) \
258 return sprintf(buf, "%llu\n", state_usage->_name);\
261 #define define_show_state_str_function(_name) \
262 static ssize_t show_state_##_name(struct cpuidle_state *state, \
263 struct cpuidle_state_usage *state_usage, char *buf) \
265 if (state->_name[0] == '\0')\
266 return sprintf(buf, "<null>\n");\
267 return sprintf(buf, "%s\n", state->_name);\
270 define_show_state_function(exit_latency)
271 define_show_state_function(power_usage)
272 define_show_state_ull_function(usage)
273 define_show_state_ull_function(time)
274 define_show_state_str_function(name)
275 define_show_state_str_function(desc)
276 define_show_state_function(disable)
277 define_store_state_function(disable)
279 define_one_state_ro(name, show_state_name);
280 define_one_state_ro(desc, show_state_desc);
281 define_one_state_ro(latency, show_state_exit_latency);
282 define_one_state_ro(power, show_state_power_usage);
283 define_one_state_ro(usage, show_state_usage);
284 define_one_state_ro(time, show_state_time);
285 define_one_state_rw(disable, show_state_disable, store_state_disable);
287 static struct attribute *cpuidle_state_default_attrs[] = {
298 #define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
299 #define kobj_to_state(k) (kobj_to_state_obj(k)->state)
300 #define kobj_to_state_usage(k) (kobj_to_state_obj(k)->state_usage)
301 #define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
302 static ssize_t cpuidle_state_show(struct kobject * kobj,
303 struct attribute * attr ,char * buf)
306 struct cpuidle_state *state = kobj_to_state(kobj);
307 struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj);
308 struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
311 ret = cattr->show(state, state_usage, buf);
316 static ssize_t cpuidle_state_store(struct kobject *kobj,
317 struct attribute *attr, const char *buf, size_t size)
320 struct cpuidle_state *state = kobj_to_state(kobj);
321 struct cpuidle_state_attr *cattr = attr_to_stateattr(attr);
324 ret = cattr->store(state, buf, size);
329 static const struct sysfs_ops cpuidle_state_sysfs_ops = {
330 .show = cpuidle_state_show,
331 .store = cpuidle_state_store,
334 static void cpuidle_state_sysfs_release(struct kobject *kobj)
336 struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
338 complete(&state_obj->kobj_unregister);
341 static struct kobj_type ktype_state_cpuidle = {
342 .sysfs_ops = &cpuidle_state_sysfs_ops,
343 .default_attrs = cpuidle_state_default_attrs,
344 .release = cpuidle_state_sysfs_release,
347 static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
349 kobject_put(&device->kobjs[i]->kobj);
350 wait_for_completion(&device->kobjs[i]->kobj_unregister);
351 kfree(device->kobjs[i]);
352 device->kobjs[i] = NULL;
356 * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
357 * @device: the target device
359 int cpuidle_add_state_sysfs(struct cpuidle_device *device)
361 int i, ret = -ENOMEM;
362 struct cpuidle_state_kobj *kobj;
363 struct cpuidle_driver *drv = cpuidle_get_driver();
365 /* state statistics */
366 for (i = 0; i < device->state_count; i++) {
367 kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
370 kobj->state = &drv->states[i];
371 kobj->state_usage = &device->states_usage[i];
372 init_completion(&kobj->kobj_unregister);
374 ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj,
380 kobject_uevent(&kobj->kobj, KOBJ_ADD);
381 device->kobjs[i] = kobj;
387 for (i = i - 1; i >= 0; i--)
388 cpuidle_free_state_kobj(device, i);
393 * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
394 * @device: the target device
396 void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
400 for (i = 0; i < device->state_count; i++)
401 cpuidle_free_state_kobj(device, i);
405 * cpuidle_add_sysfs - creates a sysfs instance for the target device
406 * @dev: the target device
408 int cpuidle_add_sysfs(struct device *cpu_dev)
410 int cpu = cpu_dev->id;
411 struct cpuidle_device *dev;
414 dev = per_cpu(cpuidle_devices, cpu);
415 error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &cpu_dev->kobj,
418 kobject_uevent(&dev->kobj, KOBJ_ADD);
423 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
424 * @dev: the target device
426 void cpuidle_remove_sysfs(struct device *cpu_dev)
428 int cpu = cpu_dev->id;
429 struct cpuidle_device *dev;
431 dev = per_cpu(cpuidle_devices, cpu);
432 kobject_put(&dev->kobj);