rtc: add devm_rtc_device_{register,unregister}()

These functions allow the driver core to automatically clean up any
allocation made by rtc drivers.  Thus it simplifies the error paths.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jingoo Han 2013-04-29 16:18:27 -07:00 committed by Linus Torvalds
parent 51b38c62aa
commit 3e217b6602
2 changed files with 76 additions and 0 deletions

View File

@ -259,6 +259,76 @@ void rtc_device_unregister(struct rtc_device *rtc)
}
EXPORT_SYMBOL_GPL(rtc_device_unregister);
static void devm_rtc_device_release(struct device *dev, void *res)
{
struct rtc_device *rtc = *(struct rtc_device **)res;
rtc_device_unregister(rtc);
}
static int devm_rtc_device_match(struct device *dev, void *res, void *data)
{
struct rtc **r = res;
return *r == data;
}
/**
* devm_rtc_device_register - resource managed rtc_device_register()
* @name: the name of the device
* @dev: the device to register
* @ops: the rtc operations structure
* @owner: the module owner
*
* @return a struct rtc on success, or an ERR_PTR on error
*
* Managed rtc_device_register(). The rtc_device returned from this function
* are automatically freed on driver detach. See rtc_device_register()
* for more information.
*/
struct rtc_device *devm_rtc_device_register(const char *name,
struct device *dev,
const struct rtc_class_ops *ops,
struct module *owner)
{
struct rtc_device **ptr, *rtc;
ptr = devres_alloc(devm_rtc_device_release, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
rtc = rtc_device_register(name, dev, ops, owner);
if (!IS_ERR(rtc)) {
*ptr = rtc;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return rtc;
}
EXPORT_SYMBOL_GPL(devm_rtc_device_register);
/**
* devm_rtc_device_unregister - resource managed devm_rtc_device_unregister()
* @dev: the device to unregister
* @rtc: the RTC class device to unregister
*
* Deallocated a rtc allocated with devm_rtc_device_register(). Normally this
* function will not need to be called and the resource management code will
* ensure that the resource is freed.
*/
void devm_rtc_device_unregister(struct device *dev, struct rtc_device *rtc)
{
int rc;
rc = devres_release(dev, devm_rtc_device_release,
devm_rtc_device_match, rtc);
WARN_ON(rc);
}
EXPORT_SYMBOL_GPL(devm_rtc_device_unregister);
static int __init rtc_init(void)
{
rtc_class = class_create(THIS_MODULE, "rtc");

View File

@ -133,7 +133,13 @@ extern struct rtc_device *rtc_device_register(const char *name,
struct device *dev,
const struct rtc_class_ops *ops,
struct module *owner);
extern struct rtc_device *devm_rtc_device_register(const char *name,
struct device *dev,
const struct rtc_class_ops *ops,
struct module *owner);
extern void rtc_device_unregister(struct rtc_device *rtc);
extern void devm_rtc_device_unregister(struct device *dev,
struct rtc_device *rtc);
extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm);
extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm);