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#include "nx-842.h"
/* this is needed, separate from the main nx-842.c driver, because that main
* driver loads the platform drivers during its init(), and it expects one
* (or none) of the platform drivers to set this pointer to its driver.
* That means this pointer can't be in the main nx-842 driver, because it
* wouldn't be accessible until after the main driver loaded, which wouldn't
* be possible as it's waiting for the platform driver to load. So place it
* here.
*/
static struct nx842_driver *driver;
static DEFINE_SPINLOCK(driver_lock);
struct nx842_driver *nx842_platform_driver(void)
{
return driver;
}
EXPORT_SYMBOL_GPL(nx842_platform_driver);
bool nx842_platform_driver_set(struct nx842_driver *_driver)
{
bool ret = false;
spin_lock(&driver_lock);
if (!driver) {
driver = _driver;
ret = true;
} else
WARN(1, "can't set platform driver, already set to %s\n",
driver->name);
spin_unlock(&driver_lock);
return ret;
}
EXPORT_SYMBOL_GPL(nx842_platform_driver_set);
/* only call this from the platform driver exit function */
void nx842_platform_driver_unset(struct nx842_driver *_driver)
{
spin_lock(&driver_lock);
if (driver == _driver)
driver = NULL;
else if (driver)
WARN(1, "can't unset platform driver %s, currently set to %s\n",
_driver->name, driver->name);
else
WARN(1, "can't unset platform driver, already unset\n");
spin_unlock(&driver_lock);
}
EXPORT_SYMBOL_GPL(nx842_platform_driver_unset);
bool nx842_platform_driver_get(void)
{
bool ret = false;
spin_lock(&driver_lock);
if (driver)
ret = try_module_get(driver->owner);
spin_unlock(&driver_lock);
return ret;
}
EXPORT_SYMBOL_GPL(nx842_platform_driver_get);
void nx842_platform_driver_put(void)
{
spin_lock(&driver_lock);
if (driver)
module_put(driver->owner);
spin_unlock(&driver_lock);
}
EXPORT_SYMBOL_GPL(nx842_platform_driver_put);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
MODULE_DESCRIPTION("842 H/W Compression platform driver");
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