lcd: add devm_lcd_device_{register,unregister}()

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

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: 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 2013-07-03 15:05:14 -07:00 committed by Linus Torvalds
parent 8318fde4ac
commit 1d0c48e66b
2 changed files with 75 additions and 0 deletions

View File

@ -260,6 +260,76 @@ void lcd_device_unregister(struct lcd_device *ld)
}
EXPORT_SYMBOL(lcd_device_unregister);
static void devm_lcd_device_release(struct device *dev, void *res)
{
struct lcd_device *lcd = *(struct lcd_device **)res;
lcd_device_unregister(lcd);
}
static int devm_lcd_device_match(struct device *dev, void *res, void *data)
{
struct lcd_device **r = res;
return *r == data;
}
/**
* devm_lcd_device_register - resource managed lcd_device_register()
* @dev: the device to register
* @name: the name of the device
* @parent: a pointer to the parent device
* @devdata: an optional pointer to be stored for private driver use
* @ops: the lcd operations structure
*
* @return a struct lcd on success, or an ERR_PTR on error
*
* Managed lcd_device_register(). The lcd_device returned from this function
* are automatically freed on driver detach. See lcd_device_register()
* for more information.
*/
struct lcd_device *devm_lcd_device_register(struct device *dev,
const char *name, struct device *parent,
void *devdata, struct lcd_ops *ops)
{
struct lcd_device **ptr, *lcd;
ptr = devres_alloc(devm_lcd_device_release, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
lcd = lcd_device_register(name, parent, devdata, ops);
if (!IS_ERR(lcd)) {
*ptr = lcd;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return lcd;
}
EXPORT_SYMBOL(devm_lcd_device_register);
/**
* devm_lcd_device_unregister - resource managed lcd_device_unregister()
* @dev: the device to unregister
* @ld: the lcd device to unregister
*
* Deallocated a lcd allocated with devm_lcd_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_lcd_device_unregister(struct device *dev, struct lcd_device *ld)
{
int rc;
rc = devres_release(dev, devm_lcd_device_release,
devm_lcd_device_match, ld);
WARN_ON(rc);
}
EXPORT_SYMBOL(devm_lcd_device_unregister);
static void __exit lcd_class_exit(void)
{
class_destroy(lcd_class);

View File

@ -112,7 +112,12 @@ static inline void lcd_set_power(struct lcd_device *ld, int power)
extern struct lcd_device *lcd_device_register(const char *name,
struct device *parent, void *devdata, struct lcd_ops *ops);
extern struct lcd_device *devm_lcd_device_register(struct device *dev,
const char *name, struct device *parent,
void *devdata, struct lcd_ops *ops);
extern void lcd_device_unregister(struct lcd_device *ld);
extern void devm_lcd_device_unregister(struct device *dev,
struct lcd_device *ld);
#define to_lcd_device(obj) container_of(obj, struct lcd_device, dev)