From 58f386560a68dd98bd6744a28fc853eef11faebe Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Mon, 27 Jun 2016 20:03:39 +0900 Subject: [PATCH] extcon: Add resource-managed functions to register extcon notifier This patch adds the resource-managed functions for register/unregister the extcon notifier with the id of each external connector. This function will make it easy to handle the extcon notifier. - int devm_extcon_register_notifier(struct device *dev, struct extcon_dev *edev, unsigned int id, struct notifier_block *nb); - void devm_extcon_unregister_notifier(struct device *dev, struct extcon_dev *edev, unsigned int id, struct notifier_block *nb); Signed-off-by: Chanwoo Choi --- drivers/extcon/devres.c | 73 +++++++++++++++++++++++++++++++++++++++++ include/linux/extcon.h | 17 ++++++++++ 2 files changed, 90 insertions(+) diff --git a/drivers/extcon/devres.c b/drivers/extcon/devres.c index 694ca85d5a70..e686acd1c459 100644 --- a/drivers/extcon/devres.c +++ b/drivers/extcon/devres.c @@ -37,6 +37,19 @@ 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); +} + /** * devm_extcon_dev_allocate - Allocate managed extcon device * @dev: device owning the extcon device being created @@ -141,3 +154,63 @@ void devm_extcon_dev_unregister(struct device *dev, struct extcon_dev *edev) devm_extcon_dev_match, edev)); } EXPORT_SYMBOL_GPL(devm_extcon_dev_unregister); + +/** + * devm_extcon_register_notifier() - Resource-managed extcon_register_notifier() + * @dev: device to allocate extcon device + * @edev: the extcon device that has the external connecotr. + * @id: the unique id of each external connector in 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: device to allocate extcon device + * @edev: the extcon device that has the external connecotr. + * @id: the unique id of each external connector in 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); diff --git a/include/linux/extcon.h b/include/linux/extcon.h index 1b2c8b6809cc..7bf530f3f4f5 100644 --- a/include/linux/extcon.h +++ b/include/linux/extcon.h @@ -182,6 +182,12 @@ extern int extcon_register_notifier(struct extcon_dev *edev, unsigned int id, struct notifier_block *nb); extern int extcon_unregister_notifier(struct extcon_dev *edev, unsigned int id, struct notifier_block *nb); +extern int devm_extcon_register_notifier(struct device *dev, + struct extcon_dev *edev, unsigned int id, + struct notifier_block *nb); +extern void devm_extcon_unregister_notifier(struct device *dev, + struct extcon_dev *edev, unsigned int id, + struct notifier_block *nb); /* * Following API get the extcon device from devicetree. @@ -273,6 +279,17 @@ static inline int extcon_unregister_notifier(struct extcon_dev *edev, return 0; } +static inline int devm_extcon_register_notifier(struct device *dev, + struct extcon_dev *edev, unsigned int id, + struct notifier_block *nb) +{ + return -ENOSYS; +} + +static inline void devm_extcon_unregister_notifier(struct device *dev, + struct extcon_dev *edev, unsigned int id, + struct notifier_block *nb) { } + static inline struct extcon_dev *extcon_get_edev_by_phandle(struct device *dev, int index) { -- 2.20.1