diff options
Diffstat (limited to 'drivers/cpuidle/driver.c')
-rw-r--r-- | drivers/cpuidle/driver.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c new file mode 100644 index 000000000000..2257004fe33d --- /dev/null +++ b/drivers/cpuidle/driver.c @@ -0,0 +1,56 @@ +/* + * driver.c - driver support + * + * (C) 2006-2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> + * Shaohua Li <shaohua.li@intel.com> + * Adam Belay <abelay@novell.com> + * + * This code is licenced under the GPL. + */ + +#include <linux/mutex.h> +#include <linux/module.h> +#include <linux/cpuidle.h> + +#include "cpuidle.h" + +struct cpuidle_driver *cpuidle_curr_driver; +DEFINE_SPINLOCK(cpuidle_driver_lock); + +/** + * cpuidle_register_driver - registers a driver + * @drv: the driver + */ +int cpuidle_register_driver(struct cpuidle_driver *drv) +{ + if (!drv) + return -EINVAL; + + spin_lock(&cpuidle_driver_lock); + if (cpuidle_curr_driver) { + spin_unlock(&cpuidle_driver_lock); + return -EBUSY; + } + cpuidle_curr_driver = drv; + spin_unlock(&cpuidle_driver_lock); + + return 0; +} + +EXPORT_SYMBOL_GPL(cpuidle_register_driver); + +/** + * cpuidle_unregister_driver - unregisters a driver + * @drv: the driver + */ +void cpuidle_unregister_driver(struct cpuidle_driver *drv) +{ + if (!drv) + return; + + spin_lock(&cpuidle_driver_lock); + cpuidle_curr_driver = NULL; + spin_unlock(&cpuidle_driver_lock); +} + +EXPORT_SYMBOL_GPL(cpuidle_unregister_driver); |