/* * 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/slab.h> #include <linux/cpu.h> #include <linux/completion.h> #include <linux/capability.h> #include <linux/device.h> #include <linux/kobject.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 device *dev, struct device_attribute *attr, 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 device *dev, struct device_attribute *attr, char *buf) { ssize_t ret; struct cpuidle_driver *drv; spin_lock(&cpuidle_driver_lock); drv = cpuidle_get_driver(); if (drv) ret = sprintf(buf, "%s\n", drv->name); else ret = sprintf(buf, "none\n"); spin_unlock(&cpuidle_driver_lock); return ret; } static ssize_t show_current_governor(struct device *dev, struct device_attribute *attr, 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 device *dev, struct device_attribute *attr, 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 DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL); static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL); static struct attribute *cpuidle_default_attrs[] = { &dev_attr_current_driver.attr, &dev_attr_current_governor_ro.attr, NULL }; static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL); static DEVICE_ATTR(current_governor, 0644, show_current_governor, store_current_governor); static struct attribute *cpuidle_switch_attrs[] = { &dev_attr_available_governors.attr, &dev_attr_current_driver.attr, &dev_attr_current_governor.attr, NULL }; static struct attribute_group cpuidle_attr_group = { .attrs = cpuidle_default_attrs, .name = "cpuidle", }; /** * cpuidle_add_interface - add CPU global sysfs attributes */ int cpuidle_add_interface(struct device *dev) { if (sysfs_switch) cpuidle_attr_group.attrs = cpuidle_switch_attrs; return sysfs_create_group(&dev->kobj, &cpuidle_attr_group); } /** * cpuidle_remove_interface - remove CPU global sysfs attributes */ void cpuidle_remove_interface(struct device *dev) { sysfs_remove_group(&dev->kobj, &cpuidle_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 attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr) struct cpuidle_device_kobj { struct cpuidle_device *dev; struct completion kobj_unregister; struct kobject kobj; }; static inline struct cpuidle_device *to_cpuidle_device(struct kobject *kobj) { struct cpuidle_device_kobj *kdev = container_of(kobj, struct cpuidle_device_kobj, kobj); return kdev->dev; } static ssize_t cpuidle_show(struct kobject *kobj, struct attribute *attr, char *buf) { int ret = -EIO; struct cpuidle_device *dev = to_cpuidle_device(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 = to_cpuidle_device(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 const struct sysfs_ops cpuidle_sysfs_ops = { .show = cpuidle_show, .store = cpuidle_store, }; static void cpuidle_sysfs_release(struct kobject *kobj) { struct cpuidle_device_kobj *kdev = container_of(kobj, struct cpuidle_device_kobj, kobj); complete(&kdev->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 *, \ struct cpuidle_state_usage *, char *); ssize_t (*store)(struct cpuidle_state *, \ struct cpuidle_state_usage *, 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_one_state_rw(_name, show, store) \ static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0644, show, store) #define define_show_state_function(_name) \ static ssize_t show_state_##_name(struct cpuidle_state *state, \ struct cpuidle_state_usage *state_usage, char *buf) \ { \ return sprintf(buf, "%u\n", state->_name);\ } #define define_store_state_ull_function(_name) \ static ssize_t store_state_##_name(struct cpuidle_state *state, \ struct cpuidle_state_usage *state_usage, \ const char *buf, size_t size) \ { \ unsigned long long value; \ int err; \ if (!capable(CAP_SYS_ADMIN)) \ return -EPERM; \ err = kstrtoull(buf, 0, &value); \ if (err) \ return err; \ if (value) \ state_usage->_name = 1; \ else \ state_usage->_name = 0; \ return size; \ } #define define_show_state_ull_function(_name) \ static ssize_t show_state_##_name(struct cpuidle_state *state, \ struct cpuidle_state_usage *state_usage, \ char *buf) \ { \ return sprintf(buf, "%llu\n", state_usage->_name);\ } #define define_show_state_str_function(_name) \ static ssize_t show_state_##_name(struct cpuidle_state *state, \ struct cpuidle_state_usage *state_usage, \ char *buf) \ { \ if (state->_name[0] == '\0')\ return sprintf(buf, "<null>\n");\ return sprintf(buf, "%s\n", state->_name);\ } define_show_state_function(exit_latency) define_show_state_function(target_residency) define_show_state_function(power_usage) define_show_state_ull_function(usage) define_show_state_ull_function(time) define_show_state_str_function(name) define_show_state_str_function(desc) define_show_state_ull_function(disable) define_store_state_ull_function(disable) define_one_state_ro(name, show_state_name); define_one_state_ro(desc, show_state_desc); define_one_state_ro(latency, show_state_exit_latency); define_one_state_ro(residency, show_state_target_residency); 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); define_one_state_rw(disable, show_state_disable, store_state_disable); static struct attribute *cpuidle_state_default_attrs[] = { &attr_name.attr, &attr_desc.attr, &attr_latency.attr, &attr_residency.attr, &attr_power.attr, &attr_usage.attr, &attr_time.attr, &attr_disable.attr, NULL }; struct cpuidle_state_kobj { struct cpuidle_state *state; struct cpuidle_state_usage *state_usage; struct completion kobj_unregister; struct kobject kobj; }; #ifdef CONFIG_SUSPEND #define define_show_state_s2idle_ull_function(_name) \ static ssize_t show_state_s2idle_##_name(struct cpuidle_state *state, \ struct cpuidle_state_usage *state_usage, \ char *buf) \ { \ return sprintf(buf, "%llu\n", state_usage->s2idle_##_name);\ } define_show_state_s2idle_ull_function(usage); define_show_state_s2idle_ull_function(time); #define define_one_state_s2idle_ro(_name, show) \ static struct cpuidle_state_attr attr_s2idle_##_name = \ __ATTR(_name, 0444, show, NULL) define_one_state_s2idle_ro(usage, show_state_s2idle_usage); define_one_state_s2idle_ro(time, show_state_s2idle_time); static struct attribute *cpuidle_state_s2idle_attrs[] = { &attr_s2idle_usage.attr, &attr_s2idle_time.attr, NULL }; static const struct attribute_group cpuidle_state_s2idle_group = { .name = "s2idle", .attrs = cpuidle_state_s2idle_attrs, }; static void cpuidle_add_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { int ret; if (!kobj->state->enter_s2idle) return; ret = sysfs_create_group(&kobj->kobj, &cpuidle_state_s2idle_group); if (ret) pr_debug("%s: sysfs attribute group not created\n", __func__); } static void cpuidle_remove_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { if (kobj->state->enter_s2idle) sysfs_remove_group(&kobj->kobj, &cpuidle_state_s2idle_group); } #else static inline void cpuidle_add_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { } static inline void cpuidle_remove_s2idle_attr_group(struct cpuidle_state_kobj *kobj) { } #endif /* CONFIG_SUSPEND */ #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 kobj_to_state_usage(k) (kobj_to_state_obj(k)->state_usage) #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_usage *state_usage = kobj_to_state_usage(kobj); struct cpuidle_state_attr * cattr = attr_to_stateattr(attr); if (cattr->show) ret = cattr->show(state, state_usage, buf); return ret; } static ssize_t cpuidle_state_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t size) { int ret = -EIO; struct cpuidle_state *state = kobj_to_state(kobj); struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj); struct cpuidle_state_attr *cattr = attr_to_stateattr(attr); if (cattr->store) ret = cattr->store(state, state_usage, buf, size); return ret; } static const struct sysfs_ops cpuidle_state_sysfs_ops = { .show = cpuidle_state_show, .store = cpuidle_state_store, }; 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 inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i) { cpuidle_remove_s2idle_attr_group(device->kobjs[i]); kobject_put(&device->kobjs[i]->kobj); wait_for_completion(&device->kobjs[i]->kobj_unregister); kfree(device->kobjs[i]); device->kobjs[i] = NULL; } /** * cpuidle_add_state_sysfs - adds cpuidle states sysfs attributes * @device: the target device */ static int cpuidle_add_state_sysfs(struct cpuidle_device *device) { int i, ret = -ENOMEM; struct cpuidle_state_kobj *kobj; struct cpuidle_device_kobj *kdev = device->kobj_dev; struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device); /* state statistics */ for (i = 0; i < drv->state_count; i++) { kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL); if (!kobj) { ret = -ENOMEM; goto error_state; } kobj->state = &drv->states[i]; kobj->state_usage = &device->states_usage[i]; init_completion(&kobj->kobj_unregister); ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &kdev->kobj, "state%d", i); if (ret) { kfree(kobj); goto error_state; } cpuidle_add_s2idle_attr_group(kobj); 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 the cpuidle states sysfs attributes * @device: the target device */ static void cpuidle_remove_state_sysfs(struct cpuidle_device *device) { struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device); int i; for (i = 0; i < drv->state_count; i++) cpuidle_free_state_kobj(device, i); } #ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS #define kobj_to_driver_kobj(k) container_of(k, struct cpuidle_driver_kobj, kobj) #define attr_to_driver_attr(a) container_of(a, struct cpuidle_driver_attr, attr) #define define_one_driver_ro(_name, show) \ static struct cpuidle_driver_attr attr_driver_##_name = \ __ATTR(_name, 0444, show, NULL) struct cpuidle_driver_kobj { struct cpuidle_driver *drv; struct completion kobj_unregister; struct kobject kobj; }; struct cpuidle_driver_attr { struct attribute attr; ssize_t (*show)(struct cpuidle_driver *, char *); ssize_t (*store)(struct cpuidle_driver *, const char *, size_t); }; static ssize_t show_driver_name(struct cpuidle_driver *drv, char *buf) { ssize_t ret; spin_lock(&cpuidle_driver_lock); ret = sprintf(buf, "%s\n", drv ? drv->name : "none"); spin_unlock(&cpuidle_driver_lock); return ret; } static void cpuidle_driver_sysfs_release(struct kobject *kobj) { struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); complete(&driver_kobj->kobj_unregister); } static ssize_t cpuidle_driver_show(struct kobject *kobj, struct attribute *attr, char *buf) { int ret = -EIO; struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); if (dattr->show) ret = dattr->show(driver_kobj->drv, buf); return ret; } static ssize_t cpuidle_driver_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t size) { int ret = -EIO; struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); if (dattr->store) ret = dattr->store(driver_kobj->drv, buf, size); return ret; } define_one_driver_ro(name, show_driver_name); static const struct sysfs_ops cpuidle_driver_sysfs_ops = { .show = cpuidle_driver_show, .store = cpuidle_driver_store, }; static struct attribute *cpuidle_driver_default_attrs[] = { &attr_driver_name.attr, NULL }; static struct kobj_type ktype_driver_cpuidle = { .sysfs_ops = &cpuidle_driver_sysfs_ops, .default_attrs = cpuidle_driver_default_attrs, .release = cpuidle_driver_sysfs_release, }; /** * cpuidle_add_driver_sysfs - adds the driver name sysfs attribute * @device: the target device */ static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) { struct cpuidle_driver_kobj *kdrv; struct cpuidle_device_kobj *kdev = dev->kobj_dev; struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); int ret; kdrv = kzalloc(sizeof(*kdrv), GFP_KERNEL); if (!kdrv) return -ENOMEM; kdrv->drv = drv; init_completion(&kdrv->kobj_unregister); ret = kobject_init_and_add(&kdrv->kobj, &ktype_driver_cpuidle, &kdev->kobj, "driver"); if (ret) { kfree(kdrv); return ret; } kobject_uevent(&kdrv->kobj, KOBJ_ADD); dev->kobj_driver = kdrv; return ret; } /** * cpuidle_remove_driver_sysfs - removes the driver name sysfs attribute * @device: the target device */ static void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) { struct cpuidle_driver_kobj *kdrv = dev->kobj_driver; kobject_put(&kdrv->kobj); wait_for_completion(&kdrv->kobj_unregister); kfree(kdrv); } #else static inline int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) { return 0; } static inline void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) { ; } #endif /** * cpuidle_add_device_sysfs - adds device specific sysfs attributes * @device: the target device */ int cpuidle_add_device_sysfs(struct cpuidle_device *device) { int ret; ret = cpuidle_add_state_sysfs(device); if (ret) return ret; ret = cpuidle_add_driver_sysfs(device); if (ret) cpuidle_remove_state_sysfs(device); return ret; } /** * cpuidle_remove_device_sysfs : removes device specific sysfs attributes * @device : the target device */ void cpuidle_remove_device_sysfs(struct cpuidle_device *device) { cpuidle_remove_driver_sysfs(device); cpuidle_remove_state_sysfs(device); } /** * cpuidle_add_sysfs - creates a sysfs instance for the target device * @dev: the target device */ int cpuidle_add_sysfs(struct cpuidle_device *dev) { struct cpuidle_device_kobj *kdev; struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu); int error; /* * Return if cpu_device is not setup for this CPU. * * This could happen if the arch did not set up cpu_device * since this CPU is not in cpu_present mask and the * driver did not send a correct CPU mask during registration. * Without this check we would end up passing bogus * value for &cpu_dev->kobj in kobject_init_and_add() */ if (!cpu_dev) return -ENODEV; kdev = kzalloc(sizeof(*kdev), GFP_KERNEL); if (!kdev) return -ENOMEM; kdev->dev = dev; dev->kobj_dev = kdev; init_completion(&kdev->kobj_unregister); error = kobject_init_and_add(&kdev->kobj, &ktype_cpuidle, &cpu_dev->kobj, "cpuidle"); if (error) { kfree(kdev); return error; } kobject_uevent(&kdev->kobj, KOBJ_ADD); return 0; } /** * cpuidle_remove_sysfs - deletes a sysfs instance on the target device * @dev: the target device */ void cpuidle_remove_sysfs(struct cpuidle_device *dev) { struct cpuidle_device_kobj *kdev = dev->kobj_dev; kobject_put(&kdev->kobj); wait_for_completion(&kdev->kobj_unregister); kfree(kdev); }