/*
 * 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);