mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-22 12:14:01 +08:00
752138df0d
cpuidle_register_driver() sets cpuidle_curr_driver cpuidle_unregister_driver() clears cpuidle_curr_driver We should't expose cpuidle_curr_driver to potential modification except via these interfaces. So make it static and create cpuidle_get_driver() to observe it. Signed-off-by: Len Brown <len.brown@intel.com>
69 lines
1.4 KiB
C
69 lines
1.4 KiB
C
/*
|
|
* 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"
|
|
|
|
static 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_get_driver - return the current driver
|
|
*/
|
|
struct cpuidle_driver *cpuidle_get_driver(void)
|
|
{
|
|
return cpuidle_curr_driver;
|
|
}
|
|
EXPORT_SYMBOL_GPL(cpuidle_get_driver);
|
|
|
|
/**
|
|
* cpuidle_unregister_driver - unregisters a driver
|
|
* @drv: the driver
|
|
*/
|
|
void cpuidle_unregister_driver(struct cpuidle_driver *drv)
|
|
{
|
|
if (drv != cpuidle_curr_driver) {
|
|
WARN(1, "invalid cpuidle_unregister_driver(%s)\n",
|
|
drv->name);
|
|
return;
|
|
}
|
|
|
|
spin_lock(&cpuidle_driver_lock);
|
|
cpuidle_curr_driver = NULL;
|
|
spin_unlock(&cpuidle_driver_lock);
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(cpuidle_unregister_driver);
|