linux/drivers/extcon/devres.c
Chanwoo Choi 6ab6094f37 extcon: Correct description to improve the readability
The extcon files explains the detailed operation for functions and
what is meaning of extcon structure. There are different explanation
even if the same argument.

So, it modifies the description for both functions and structures
in order to improve the readability and guide the role of functions
more well.

Also, this patch fixes the mismatching license info as a GPL v2
and removes the inactive author information.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2017-08-16 09:27:55 +09:00

276 lines
7.7 KiB
C

/*
* drivers/extcon/devres.c - EXTCON device's resource management
*
* Copyright (C) 2016 Samsung Electronics
* Author: Chanwoo Choi <cw00.choi@samsung.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include "extcon.h"
static int devm_extcon_dev_match(struct device *dev, void *res, void *data)
{
struct extcon_dev **r = res;
if (WARN_ON(!r || !*r))
return 0;
return *r == data;
}
static void devm_extcon_dev_release(struct device *dev, void *res)
{
extcon_dev_free(*(struct extcon_dev **)res);
}
static void devm_extcon_dev_unreg(struct device *dev, void *res)
{
extcon_dev_unregister(*(struct extcon_dev **)res);
}
struct extcon_dev_notifier_devres {
struct extcon_dev *edev;
unsigned int id;
struct notifier_block *nb;
};
static void devm_extcon_dev_notifier_unreg(struct device *dev, void *res)
{
struct extcon_dev_notifier_devres *this = res;
extcon_unregister_notifier(this->edev, this->id, this->nb);
}
static void devm_extcon_dev_notifier_all_unreg(struct device *dev, void *res)
{
struct extcon_dev_notifier_devres *this = res;
extcon_unregister_notifier_all(this->edev, this->nb);
}
/**
* devm_extcon_dev_allocate - Allocate managed extcon device
* @dev: the device owning the extcon device being created
* @supported_cable: the array of the supported external connectors
* ending with EXTCON_NONE.
*
* This function manages automatically the memory of extcon device using device
* resource management and simplify the control of freeing the memory of extcon
* device.
*
* Returns the pointer memory of allocated extcon_dev if success
* or ERR_PTR(err) if fail
*/
struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
const unsigned int *supported_cable)
{
struct extcon_dev **ptr, *edev;
ptr = devres_alloc(devm_extcon_dev_release, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
edev = extcon_dev_allocate(supported_cable);
if (IS_ERR(edev)) {
devres_free(ptr);
return edev;
}
edev->dev.parent = dev;
*ptr = edev;
devres_add(dev, ptr);
return edev;
}
EXPORT_SYMBOL_GPL(devm_extcon_dev_allocate);
/**
* devm_extcon_dev_free() - Resource-managed extcon_dev_unregister()
* @dev: the device owning the extcon device being created
* @edev: the extcon device to be freed
*
* Free the memory that is allocated with devm_extcon_dev_allocate()
* function.
*/
void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev)
{
WARN_ON(devres_release(dev, devm_extcon_dev_release,
devm_extcon_dev_match, edev));
}
EXPORT_SYMBOL_GPL(devm_extcon_dev_free);
/**
* devm_extcon_dev_register() - Resource-managed extcon_dev_register()
* @dev: the device owning the extcon device being created
* @edev: the extcon device to be registered
*
* this function, that extcon device is automatically unregistered on driver
* detach. Internally this function calls extcon_dev_register() function.
* To get more information, refer that function.
*
* If extcon device is registered with this function and the device needs to be
* unregistered separately, devm_extcon_dev_unregister() should be used.
*
* Returns 0 if success or negaive error number if failure.
*/
int devm_extcon_dev_register(struct device *dev, struct extcon_dev *edev)
{
struct extcon_dev **ptr;
int ret;
ptr = devres_alloc(devm_extcon_dev_unreg, sizeof(*ptr), GFP_KERNEL);
if (!ptr)
return -ENOMEM;
ret = extcon_dev_register(edev);
if (ret) {
devres_free(ptr);
return ret;
}
*ptr = edev;
devres_add(dev, ptr);
return 0;
}
EXPORT_SYMBOL_GPL(devm_extcon_dev_register);
/**
* devm_extcon_dev_unregister() - Resource-managed extcon_dev_unregister()
* @dev: the device owning the extcon device being created
* @edev: the extcon device to unregistered
*
* Unregister extcon device that is registered with devm_extcon_dev_register()
* function.
*/
void devm_extcon_dev_unregister(struct device *dev, struct extcon_dev *edev)
{
WARN_ON(devres_release(dev, devm_extcon_dev_unreg,
devm_extcon_dev_match, edev));
}
EXPORT_SYMBOL_GPL(devm_extcon_dev_unregister);
/**
* devm_extcon_register_notifier() - Resource-managed extcon_register_notifier()
* @dev: the device owning the extcon device being created
* @edev: the extcon device
* @id: the unique id among the extcon enumeration
* @nb: a notifier block to be registered
*
* This function manages automatically the notifier of extcon device using
* device resource management and simplify the control of unregistering
* the notifier of extcon device.
*
* Note that the second parameter given to the callback of nb (val) is
* "old_state", not the current state. The current state can be retrieved
* by looking at the third pameter (edev pointer)'s state value.
*
* Returns 0 if success or negaive error number if failure.
*/
int devm_extcon_register_notifier(struct device *dev, struct extcon_dev *edev,
unsigned int id, struct notifier_block *nb)
{
struct extcon_dev_notifier_devres *ptr;
int ret;
ptr = devres_alloc(devm_extcon_dev_notifier_unreg, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return -ENOMEM;
ret = extcon_register_notifier(edev, id, nb);
if (ret) {
devres_free(ptr);
return ret;
}
ptr->edev = edev;
ptr->id = id;
ptr->nb = nb;
devres_add(dev, ptr);
return 0;
}
EXPORT_SYMBOL(devm_extcon_register_notifier);
/**
* devm_extcon_unregister_notifier()
- Resource-managed extcon_unregister_notifier()
* @dev: the device owning the extcon device being created
* @edev: the extcon device
* @id: the unique id among the extcon enumeration
* @nb: a notifier block to be registered
*/
void devm_extcon_unregister_notifier(struct device *dev,
struct extcon_dev *edev, unsigned int id,
struct notifier_block *nb)
{
WARN_ON(devres_release(dev, devm_extcon_dev_notifier_unreg,
devm_extcon_dev_match, edev));
}
EXPORT_SYMBOL(devm_extcon_unregister_notifier);
/**
* devm_extcon_register_notifier_all()
* - Resource-managed extcon_register_notifier_all()
* @dev: the device owning the extcon device being created
* @edev: the extcon device
* @nb: a notifier block to be registered
*
* This function manages automatically the notifier of extcon device using
* device resource management and simplify the control of unregistering
* the notifier of extcon device. To get more information, refer that function.
*
* Returns 0 if success or negaive error number if failure.
*/
int devm_extcon_register_notifier_all(struct device *dev, struct extcon_dev *edev,
struct notifier_block *nb)
{
struct extcon_dev_notifier_devres *ptr;
int ret;
ptr = devres_alloc(devm_extcon_dev_notifier_all_unreg, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return -ENOMEM;
ret = extcon_register_notifier_all(edev, nb);
if (ret) {
devres_free(ptr);
return ret;
}
ptr->edev = edev;
ptr->nb = nb;
devres_add(dev, ptr);
return 0;
}
EXPORT_SYMBOL(devm_extcon_register_notifier_all);
/**
* devm_extcon_unregister_notifier_all()
* - Resource-managed extcon_unregister_notifier_all()
* @dev: the device owning the extcon device being created
* @edev: the extcon device
* @nb: a notifier block to be registered
*/
void devm_extcon_unregister_notifier_all(struct device *dev,
struct extcon_dev *edev,
struct notifier_block *nb)
{
WARN_ON(devres_release(dev, devm_extcon_dev_notifier_all_unreg,
devm_extcon_dev_match, edev));
}
EXPORT_SYMBOL(devm_extcon_unregister_notifier_all);