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>
17 static unsigned int sysfs_switch;
18 static int __init cpuidle_sysfs_setup(char *unused)
23 __setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);
25 static ssize_t show_available_governors(struct sysdev_class *class,
26 struct sysdev_class_attribute *attr,
30 struct cpuidle_governor *tmp;
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))
36 i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
40 i+= sprintf(&buf[i], "\n");
41 mutex_unlock(&cpuidle_lock);
45 static ssize_t show_current_driver(struct sysdev_class *class,
46 struct sysdev_class_attribute *attr,
50 struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
52 spin_lock(&cpuidle_driver_lock);
54 ret = sprintf(buf, "%s\n", cpuidle_driver->name);
56 ret = sprintf(buf, "none\n");
57 spin_unlock(&cpuidle_driver_lock);
62 static ssize_t show_current_governor(struct sysdev_class *class,
63 struct sysdev_class_attribute *attr,
68 mutex_lock(&cpuidle_lock);
69 if (cpuidle_curr_governor)
70 ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
72 ret = sprintf(buf, "none\n");
73 mutex_unlock(&cpuidle_lock);
78 static ssize_t store_current_governor(struct sysdev_class *class,
79 struct sysdev_class_attribute *attr,
80 const char *buf, size_t count)
82 char gov_name[CPUIDLE_NAME_LEN];
85 struct cpuidle_governor *gov;
87 if (!len || len >= sizeof(gov_name))
90 memcpy(gov_name, buf, len);
92 if (gov_name[len - 1] == '\n')
93 gov_name[--len] = '\0';
95 mutex_lock(&cpuidle_lock);
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);
104 mutex_unlock(&cpuidle_lock);
112 static SYSDEV_CLASS_ATTR(current_driver, 0444, show_current_driver, NULL);
113 static SYSDEV_CLASS_ATTR(current_governor_ro, 0444, show_current_governor,
116 static struct attribute *cpuclass_default_attrs[] = {
117 &attr_current_driver.attr,
118 &attr_current_governor_ro.attr,
122 static SYSDEV_CLASS_ATTR(available_governors, 0444, show_available_governors,
124 static SYSDEV_CLASS_ATTR(current_governor, 0644, show_current_governor,
125 store_current_governor);
127 static struct attribute *cpuclass_switch_attrs[] = {
128 &attr_available_governors.attr,
129 &attr_current_driver.attr,
130 &attr_current_governor.attr,
134 static struct attribute_group cpuclass_attr_group = {
135 .attrs = cpuclass_default_attrs,
140 * cpuidle_add_class_sysfs - add CPU global sysfs attributes
142 int cpuidle_add_class_sysfs(struct sysdev_class *cls)
145 cpuclass_attr_group.attrs = cpuclass_switch_attrs;
147 return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
151 * cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
153 void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
155 sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group);
158 struct 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);
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)
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)
171 static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
174 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
175 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
178 mutex_lock(&cpuidle_lock);
179 ret = cattr->show(dev, buf);
180 mutex_unlock(&cpuidle_lock);
185 static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
186 const char * buf, size_t count)
189 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
190 struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
193 mutex_lock(&cpuidle_lock);
194 ret = cattr->store(dev, buf, count);
195 mutex_unlock(&cpuidle_lock);
200 static const struct sysfs_ops cpuidle_sysfs_ops = {
201 .show = cpuidle_show,
202 .store = cpuidle_store,
205 static void cpuidle_sysfs_release(struct kobject *kobj)
207 struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
209 complete(&dev->kobj_unregister);
212 static struct kobj_type ktype_cpuidle = {
213 .sysfs_ops = &cpuidle_sysfs_ops,
214 .release = cpuidle_sysfs_release,
217 struct 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);
223 #define define_one_state_ro(_name, show) \
224 static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
226 #define define_show_state_function(_name) \
227 static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
229 return sprintf(buf, "%u\n", state->_name);\
232 #define define_show_state_ull_function(_name) \
233 static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
235 return sprintf(buf, "%llu\n", state->_name);\
238 #define define_show_state_str_function(_name) \
239 static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
241 if (state->_name[0] == '\0')\
242 return sprintf(buf, "<null>\n");\
243 return sprintf(buf, "%s\n", state->_name);\
246 define_show_state_function(exit_latency)
247 define_show_state_function(power_usage)
248 define_show_state_ull_function(usage)
249 define_show_state_ull_function(time)
250 define_show_state_str_function(name)
251 define_show_state_str_function(desc)
253 define_one_state_ro(name, show_state_name);
254 define_one_state_ro(desc, show_state_desc);
255 define_one_state_ro(latency, show_state_exit_latency);
256 define_one_state_ro(power, show_state_power_usage);
257 define_one_state_ro(usage, show_state_usage);
258 define_one_state_ro(time, show_state_time);
260 static struct attribute *cpuidle_state_default_attrs[] = {
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)
273 static ssize_t cpuidle_state_show(struct kobject * kobj,
274 struct attribute * attr ,char * buf)
277 struct cpuidle_state *state = kobj_to_state(kobj);
278 struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
281 ret = cattr->show(state, buf);
286 static const struct sysfs_ops cpuidle_state_sysfs_ops = {
287 .show = cpuidle_state_show,
290 static void cpuidle_state_sysfs_release(struct kobject *kobj)
292 struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
294 complete(&state_obj->kobj_unregister);
297 static 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,
303 static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
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;
312 * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
313 * @device: the target device
315 int cpuidle_add_state_sysfs(struct cpuidle_device *device)
317 int i, ret = -ENOMEM;
318 struct cpuidle_state_kobj *kobj;
320 /* state statistics */
321 for (i = 0; i < device->state_count; i++) {
322 kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
325 kobj->state = &device->states[i];
326 init_completion(&kobj->kobj_unregister);
328 ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj,
334 kobject_uevent(&kobj->kobj, KOBJ_ADD);
335 device->kobjs[i] = kobj;
341 for (i = i - 1; i >= 0; i--)
342 cpuidle_free_state_kobj(device, i);
347 * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
348 * @device: the target device
350 void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
354 for (i = 0; i < device->state_count; i++)
355 cpuidle_free_state_kobj(device, i);
359 * cpuidle_add_sysfs - creates a sysfs instance for the target device
360 * @sysdev: the target device
362 int cpuidle_add_sysfs(struct sys_device *sysdev)
364 int cpu = sysdev->id;
365 struct cpuidle_device *dev;
368 dev = per_cpu(cpuidle_devices, cpu);
369 error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj,
372 kobject_uevent(&dev->kobj, KOBJ_ADD);
377 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
378 * @sysdev: the target device
380 void cpuidle_remove_sysfs(struct sys_device *sysdev)
382 int cpu = sysdev->id;
383 struct cpuidle_device *dev;
385 dev = per_cpu(cpuidle_devices, cpu);
386 kobject_put(&dev->kobj);