/**
* cpuidle_switch_governor - changes the governor
* @gov: the new target governor
*
* NOTE: "gov" can be NULL to specify disabled
* Must be called with cpuidle_lock acquired.
*/
int cpuidle_switch_governor(struct cpuidle_governor *gov)
{
struct cpuidle_device *dev;
if (gov == cpuidle_curr_governor)
return 0;
cpuidle_uninstall_idle_handler();
if (cpuidle_curr_governor) {
list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
cpuidle_disable_device(dev);
module_put(cpuidle_curr_governor->owner);
}
cpuidle_curr_governor = gov;
if (gov) {
if (!try_module_get(cpuidle_curr_governor->owner))
return -EINVAL;
list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
cpuidle_enable_device(dev);
cpuidle_install_idle_handler();
printk(KERN_INFO "cpuidle: using governor %s\n", gov->name);
}
return 0;
}
/**
* cpuidle_register_device - registers a CPU's idle PM feature
* @dev: the cpu
*/
int cpuidle_register_device(struct cpuidle_device *dev)
{
int ret;
struct sys_device *sys_dev = get_cpu_sysdev((unsigned long)dev->cpu);
if (!sys_dev)
return -EINVAL;
if (!try_module_get(cpuidle_curr_driver->owner))
return -EINVAL;
init_completion(&dev->kobj_unregister);
mutex_lock(&cpuidle_lock);
poll_idle_init(dev);
per_cpu(cpuidle_devices, dev->cpu) = dev;
list_add(&dev->device_list, &cpuidle_detected_devices);
if ((ret = cpuidle_add_sysfs(sys_dev))) {
mutex_unlock(&cpuidle_lock);
module_put(cpuidle_curr_driver->owner);
return ret;
}
cpuidle_enable_device(dev);
cpuidle_install_idle_handler();
mutex_unlock(&cpuidle_lock);
return 0;
}
int cpuidle_register_device(struct cpuidle_device *dev)
{
int ret;
mutex_lock(&cpuidle_lock);
if ((ret = __cpuidle_register_device(dev))) {
mutex_unlock(&cpuidle_lock);
return ret;
}
cpuidle_enable_device(dev);
cpuidle_install_idle_handler();
mutex_unlock(&cpuidle_lock);
return 0;
}
void cpuidle_resume_and_unlock(void)
{
cpuidle_install_idle_handler();
mutex_unlock(&cpuidle_lock);
}
/* Currently used in suspend/resume path to resume cpuidle */
void cpuidle_resume(void)
{
mutex_lock(&cpuidle_lock);
cpuidle_install_idle_handler();
mutex_unlock(&cpuidle_lock);
}
