| /* |
| * sysfs.c - sysfs support |
| * |
| * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com> |
| * |
| * This code is licenced under the GPL. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/cpuidle.h> |
| #include <linux/sysfs.h> |
| #include <linux/cpu.h> |
| |
| #include "cpuidle.h" |
| |
| static unsigned int sysfs_switch; |
| static int __init cpuidle_sysfs_setup(char *unused) |
| { |
| sysfs_switch = 1; |
| return 1; |
| } |
| __setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup); |
| |
| static ssize_t show_available_governors(struct sys_device *dev, char *buf) |
| { |
| ssize_t i = 0; |
| struct cpuidle_governor *tmp; |
| |
| mutex_lock(&cpuidle_lock); |
| list_for_each_entry(tmp, &cpuidle_governors, governor_list) { |
| if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2)) |
| goto out; |
| i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name); |
| } |
| |
| out: |
| i+= sprintf(&buf[i], "\n"); |
| mutex_unlock(&cpuidle_lock); |
| return i; |
| } |
| |
| static ssize_t show_current_driver(struct sys_device *dev, char *buf) |
| { |
| ssize_t ret; |
| |
| spin_lock(&cpuidle_driver_lock); |
| if (cpuidle_curr_driver) |
| ret = sprintf(buf, "%s\n", cpuidle_curr_driver->name); |
| else |
| ret = sprintf(buf, "none\n"); |
| spin_unlock(&cpuidle_driver_lock); |
| |
| return ret; |
| } |
| |
| static ssize_t show_current_governor(struct sys_device *dev, char *buf) |
| { |
| ssize_t ret; |
| |
| mutex_lock(&cpuidle_lock); |
| if (cpuidle_curr_governor) |
| ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name); |
| else |
| ret = sprintf(buf, "none\n"); |
| mutex_unlock(&cpuidle_lock); |
| |
| return ret; |
| } |
| |
| static ssize_t store_current_governor(struct sys_device *dev, |
| const char *buf, size_t count) |
| { |
| char gov_name[CPUIDLE_NAME_LEN]; |
| int ret = -EINVAL; |
| size_t len = count; |
| struct cpuidle_governor *gov; |
| |
| if (!len || len >= sizeof(gov_name)) |
| return -EINVAL; |
| |
| memcpy(gov_name, buf, len); |
| gov_name[len] = '\0'; |
| if (gov_name[len - 1] == '\n') |
| gov_name[--len] = '\0'; |
| |
| mutex_lock(&cpuidle_lock); |
| |
| list_for_each_entry(gov, &cpuidle_governors, governor_list) { |
| if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) { |
| ret = cpuidle_switch_governor(gov); |
| break; |
| } |
| } |
| |
| mutex_unlock(&cpuidle_lock); |
| |
| if (ret) |
| return ret; |
| else |
| return count; |
| } |
| |
| static SYSDEV_ATTR(current_driver, 0444, show_current_driver, NULL); |
| static SYSDEV_ATTR(current_governor_ro, 0444, show_current_governor, NULL); |
| |
| static struct attribute *cpuclass_default_attrs[] = { |
| &attr_current_driver.attr, |
| &attr_current_governor_ro.attr, |
| NULL |
| }; |
| |
| static SYSDEV_ATTR(available_governors, 0444, show_available_governors, NULL); |
| static SYSDEV_ATTR(current_governor, 0644, show_current_governor, |
| store_current_governor); |
| |
| static struct attribute *cpuclass_switch_attrs[] = { |
| &attr_available_governors.attr, |
| &attr_current_driver.attr, |
| &attr_current_governor.attr, |
| NULL |
| }; |
| |
| static struct attribute_group cpuclass_attr_group = { |
| .attrs = cpuclass_default_attrs, |
| .name = "cpuidle", |
| }; |
| |
| /** |
| * cpuidle_add_class_sysfs - add CPU global sysfs attributes |
| */ |
| int cpuidle_add_class_sysfs(struct sysdev_class *cls) |
| { |
| if (sysfs_switch) |
| cpuclass_attr_group.attrs = cpuclass_switch_attrs; |
| |
| return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group); |
| } |
| |
| /** |
| * cpuidle_remove_class_sysfs - remove CPU global sysfs attributes |
| */ |
| void cpuidle_remove_class_sysfs(struct sysdev_class *cls) |
| { |
| sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group); |
| } |
| |
| struct cpuidle_attr { |
| struct attribute attr; |
| ssize_t (*show)(struct cpuidle_device *, char *); |
| ssize_t (*store)(struct cpuidle_device *, const char *, size_t count); |
| }; |
| |
| #define define_one_ro(_name, show) \ |
| static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL) |
| #define define_one_rw(_name, show, store) \ |
| static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store) |
| |
| #define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj) |
| #define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr) |
| static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf) |
| { |
| int ret = -EIO; |
| struct cpuidle_device *dev = kobj_to_cpuidledev(kobj); |
| struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr); |
| |
| if (cattr->show) { |
| mutex_lock(&cpuidle_lock); |
| ret = cattr->show(dev, buf); |
| mutex_unlock(&cpuidle_lock); |
| } |
| return ret; |
| } |
| |
| static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr, |
| const char * buf, size_t count) |
| { |
| int ret = -EIO; |
| struct cpuidle_device *dev = kobj_to_cpuidledev(kobj); |
| struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr); |
| |
| if (cattr->store) { |
| mutex_lock(&cpuidle_lock); |
| ret = cattr->store(dev, buf, count); |
| mutex_unlock(&cpuidle_lock); |
| } |
| return ret; |
| } |
| |
| static struct sysfs_ops cpuidle_sysfs_ops = { |
| .show = cpuidle_show, |
| .store = cpuidle_store, |
| }; |
| |
| static void cpuidle_sysfs_release(struct kobject *kobj) |
| { |
| struct cpuidle_device *dev = kobj_to_cpuidledev(kobj); |
| |
| complete(&dev->kobj_unregister); |
| } |
| |
| static struct kobj_type ktype_cpuidle = { |
| .sysfs_ops = &cpuidle_sysfs_ops, |
| .release = cpuidle_sysfs_release, |
| }; |
| |
| struct cpuidle_state_attr { |
| struct attribute attr; |
| ssize_t (*show)(struct cpuidle_state *, char *); |
| ssize_t (*store)(struct cpuidle_state *, const char *, size_t); |
| }; |
| |
| #define define_one_state_ro(_name, show) \ |
| static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL) |
| |
| #define define_show_state_function(_name) \ |
| static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \ |
| { \ |
| return sprintf(buf, "%u\n", state->_name);\ |
| } |
| |
| static ssize_t show_state_name(struct cpuidle_state *state, char *buf) |
| { |
| return sprintf(buf, "%s\n", state->name); |
| } |
| |
| define_show_state_function(exit_latency) |
| define_show_state_function(power_usage) |
| define_show_state_function(usage) |
| define_show_state_function(time) |
| define_one_state_ro(name, show_state_name); |
| define_one_state_ro(latency, show_state_exit_latency); |
| define_one_state_ro(power, show_state_power_usage); |
| define_one_state_ro(usage, show_state_usage); |
| define_one_state_ro(time, show_state_time); |
| |
| static struct attribute *cpuidle_state_default_attrs[] = { |
| &attr_name.attr, |
| &attr_latency.attr, |
| &attr_power.attr, |
| &attr_usage.attr, |
| &attr_time.attr, |
| NULL |
| }; |
| |
| #define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj) |
| #define kobj_to_state(k) (kobj_to_state_obj(k)->state) |
| #define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr) |
| static ssize_t cpuidle_state_show(struct kobject * kobj, |
| struct attribute * attr ,char * buf) |
| { |
| int ret = -EIO; |
| struct cpuidle_state *state = kobj_to_state(kobj); |
| struct cpuidle_state_attr * cattr = attr_to_stateattr(attr); |
| |
| if (cattr->show) |
| ret = cattr->show(state, buf); |
| |
| return ret; |
| } |
| |
| static struct sysfs_ops cpuidle_state_sysfs_ops = { |
| .show = cpuidle_state_show, |
| }; |
| |
| static void cpuidle_state_sysfs_release(struct kobject *kobj) |
| { |
| struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj); |
| |
| complete(&state_obj->kobj_unregister); |
| } |
| |
| static struct kobj_type ktype_state_cpuidle = { |
| .sysfs_ops = &cpuidle_state_sysfs_ops, |
| .default_attrs = cpuidle_state_default_attrs, |
| .release = cpuidle_state_sysfs_release, |
| }; |
| |
| static void inline cpuidle_free_state_kobj(struct cpuidle_device *device, int i) |
| { |
| kobject_unregister(&device->kobjs[i]->kobj); |
| wait_for_completion(&device->kobjs[i]->kobj_unregister); |
| kfree(device->kobjs[i]); |
| device->kobjs[i] = NULL; |
| } |
| |
| /** |
| * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes |
| * @device: the target device |
| */ |
| int cpuidle_add_state_sysfs(struct cpuidle_device *device) |
| { |
| int i, ret = -ENOMEM; |
| struct cpuidle_state_kobj *kobj; |
| |
| /* state statistics */ |
| for (i = 0; i < device->state_count; i++) { |
| kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL); |
| if (!kobj) |
| goto error_state; |
| kobj->state = &device->states[i]; |
| init_completion(&kobj->kobj_unregister); |
| |
| ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj, |
| "state%d", i); |
| if (ret) { |
| kfree(kobj); |
| goto error_state; |
| } |
| kobject_uevent(&kobj->kobj, KOBJ_ADD); |
| device->kobjs[i] = kobj; |
| } |
| |
| return 0; |
| |
| error_state: |
| for (i = i - 1; i >= 0; i--) |
| cpuidle_free_state_kobj(device, i); |
| return ret; |
| } |
| |
| /** |
| * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes |
| * @device: the target device |
| */ |
| void cpuidle_remove_state_sysfs(struct cpuidle_device *device) |
| { |
| int i; |
| |
| for (i = 0; i < device->state_count; i++) |
| cpuidle_free_state_kobj(device, i); |
| } |
| |
| /** |
| * cpuidle_add_sysfs - creates a sysfs instance for the target device |
| * @sysdev: the target device |
| */ |
| int cpuidle_add_sysfs(struct sys_device *sysdev) |
| { |
| int cpu = sysdev->id; |
| struct cpuidle_device *dev; |
| int error; |
| |
| dev = per_cpu(cpuidle_devices, cpu); |
| error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj, |
| "cpuidle"); |
| if (!error) |
| kobject_uevent(&dev->kobj, KOBJ_ADD); |
| return error; |
| } |
| |
| /** |
| * cpuidle_remove_sysfs - deletes a sysfs instance on the target device |
| * @sysdev: the target device |
| */ |
| void cpuidle_remove_sysfs(struct sys_device *sysdev) |
| { |
| int cpu = sysdev->id; |
| struct cpuidle_device *dev; |
| |
| dev = per_cpu(cpuidle_devices, cpu); |
| kobject_unregister(&dev->kobj); |
| } |