/* SPDX-License-Identifier: GPL-2.0 */ /* * devres.c - managed gpio resources * This file is based on kernel/irq/devres.c * * Copyright (c) 2011 John Crispin */ #include #include #include #include #include #include #include "gpiolib.h" static void devm_gpiod_release(struct device *dev, void *res) { struct gpio_desc **desc = res; gpiod_put(*desc); } static int devm_gpiod_match(struct device *dev, void *res, void *data) { struct gpio_desc **this = res, **gpio = data; return *this == *gpio; } static void devm_gpiod_release_array(struct device *dev, void *res) { struct gpio_descs **descs = res; gpiod_put_array(*descs); } static int devm_gpiod_match_array(struct device *dev, void *res, void *data) { struct gpio_descs **this = res, **gpios = data; return *this == *gpios; } /** * devm_gpiod_get - Resource-managed gpiod_get() * @dev: GPIO consumer * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * Managed gpiod_get(). GPIO descriptors returned from this function are * automatically disposed on driver detach. See gpiod_get() for detailed * information about behavior and return values. */ struct gpio_desc *__must_check devm_gpiod_get(struct device *dev, const char *con_id, enum gpiod_flags flags) { return devm_gpiod_get_index(dev, con_id, 0, flags); } EXPORT_SYMBOL_GPL(devm_gpiod_get); /** * devm_gpiod_get_optional - Resource-managed gpiod_get_optional() * @dev: GPIO consumer * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * Managed gpiod_get_optional(). GPIO descriptors returned from this function * are automatically disposed on driver detach. See gpiod_get_optional() for * detailed information about behavior and return values. */ struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev, const char *con_id, enum gpiod_flags flags) { return devm_gpiod_get_index_optional(dev, con_id, 0, flags); } EXPORT_SYMBOL_GPL(devm_gpiod_get_optional); /** * devm_gpiod_get_index - Resource-managed gpiod_get_index() * @dev: GPIO consumer * @con_id: function within the GPIO consumer * @idx: index of the GPIO to obtain in the consumer * @flags: optional GPIO initialization flags * * Managed gpiod_get_index(). GPIO descriptors returned from this function are * automatically disposed on driver detach. See gpiod_get_index() for detailed * information about behavior and return values. */ struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev, const char *con_id, unsigned int idx, enum gpiod_flags flags) { struct gpio_desc **dr; struct gpio_desc *desc; desc = gpiod_get_index(dev, con_id, idx, flags); if (IS_ERR(desc)) return desc; /* * For non-exclusive GPIO descriptors, check if this descriptor is * already under resource management by this device. */ if (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) { struct devres *dres; dres = devres_find(dev, devm_gpiod_release, devm_gpiod_match, &desc); if (dres) return desc; } dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *), GFP_KERNEL); if (!dr) { gpiod_put(desc); return ERR_PTR(-ENOMEM); } *dr = desc; devres_add(dev, dr); return desc; } EXPORT_SYMBOL_GPL(devm_gpiod_get_index); /** * devm_fwnode_gpiod_get_index - get a GPIO descriptor from a given node * @dev: GPIO consumer * @fwnode: firmware node containing GPIO reference * @con_id: function within the GPIO consumer * @index: index of the GPIO to obtain in the consumer * @flags: GPIO initialization flags * @label: label to attach to the requested GPIO * * GPIO descriptors returned from this function are automatically disposed on * driver detach. * * On successful request the GPIO pin is configured in accordance with * provided @flags. */ struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev, struct fwnode_handle *fwnode, const char *con_id, int index, enum gpiod_flags flags, const char *label) { struct gpio_desc **dr; struct gpio_desc *desc; dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *), GFP_KERNEL); if (!dr) return ERR_PTR(-ENOMEM); desc = gpiod_find_and_request(dev, fwnode, con_id, index, flags, label, false); if (IS_ERR(desc)) { devres_free(dr); return desc; } *dr = desc; devres_add(dev, dr); return desc; } EXPORT_SYMBOL_GPL(devm_fwnode_gpiod_get_index); /** * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional() * @dev: GPIO consumer * @con_id: function within the GPIO consumer * @index: index of the GPIO to obtain in the consumer * @flags: optional GPIO initialization flags * * Managed gpiod_get_index_optional(). GPIO descriptors returned from this * function are automatically disposed on driver detach. See * gpiod_get_index_optional() for detailed information about behavior and * return values. */ struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev, const char *con_id, unsigned int index, enum gpiod_flags flags) { struct gpio_desc *desc; desc = devm_gpiod_get_index(dev, con_id, index, flags); if (gpiod_not_found(desc)) return NULL; return desc; } EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional); /** * devm_gpiod_get_array - Resource-managed gpiod_get_array() * @dev: GPIO consumer * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * Managed gpiod_get_array(). GPIO descriptors returned from this function are * automatically disposed on driver detach. See gpiod_get_array() for detailed * information about behavior and return values. */ struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev, const char *con_id, enum gpiod_flags flags) { struct gpio_descs **dr; struct gpio_descs *descs; dr = devres_alloc(devm_gpiod_release_array, sizeof(struct gpio_descs *), GFP_KERNEL); if (!dr) return ERR_PTR(-ENOMEM); descs = gpiod_get_array(dev, con_id, flags); if (IS_ERR(descs)) { devres_free(dr); return descs; } *dr = descs; devres_add(dev, dr); return descs; } EXPORT_SYMBOL_GPL(devm_gpiod_get_array); /** * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional() * @dev: GPIO consumer * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * * Managed gpiod_get_array_optional(). GPIO descriptors returned from this * function are automatically disposed on driver detach. * See gpiod_get_array_optional() for detailed information about behavior and * return values. */ struct gpio_descs *__must_check devm_gpiod_get_array_optional(struct device *dev, const char *con_id, enum gpiod_flags flags) { struct gpio_descs *descs; descs = devm_gpiod_get_array(dev, con_id, flags); if (gpiod_not_found(descs)) return NULL; return descs; } EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional); /** * devm_gpiod_put - Resource-managed gpiod_put() * @dev: GPIO consumer * @desc: GPIO descriptor to dispose of * * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or * devm_gpiod_get_index(). Normally this function will not be called as the GPIO * will be disposed of by the resource management code. */ void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) { WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match, &desc)); } EXPORT_SYMBOL_GPL(devm_gpiod_put); /** * devm_gpiod_unhinge - Remove resource management from a gpio descriptor * @dev: GPIO consumer * @desc: GPIO descriptor to remove resource management from * * Remove resource management from a GPIO descriptor. This is needed when * you want to hand over lifecycle management of a descriptor to another * mechanism. */ void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc) { int ret; if (IS_ERR_OR_NULL(desc)) return; ret = devres_destroy(dev, devm_gpiod_release, devm_gpiod_match, &desc); /* * If the GPIO descriptor is requested as nonexclusive, we * may call this function several times on the same descriptor * so it is OK if devres_destroy() returns -ENOENT. */ if (ret == -ENOENT) return; /* Anything else we should warn about */ WARN_ON(ret); } EXPORT_SYMBOL_GPL(devm_gpiod_unhinge); /** * devm_gpiod_put_array - Resource-managed gpiod_put_array() * @dev: GPIO consumer * @descs: GPIO descriptor array to dispose of * * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array(). * Normally this function will not be called as the GPIOs will be disposed of * by the resource management code. */ void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs) { WARN_ON(devres_release(dev, devm_gpiod_release_array, devm_gpiod_match_array, &descs)); } EXPORT_SYMBOL_GPL(devm_gpiod_put_array); static void devm_gpio_release(struct device *dev, void *res) { unsigned *gpio = res; gpio_free(*gpio); } /** * devm_gpio_request - request a GPIO for a managed device * @dev: device to request the GPIO for * @gpio: GPIO to allocate * @label: the name of the requested GPIO * * Except for the extra @dev argument, this function takes the * same arguments and performs the same function as * gpio_request(). GPIOs requested with this function will be * automatically freed on driver detach. */ int devm_gpio_request(struct device *dev, unsigned gpio, const char *label) { unsigned *dr; int rc; dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL); if (!dr) return -ENOMEM; rc = gpio_request(gpio, label); if (rc) { devres_free(dr); return rc; } *dr = gpio; devres_add(dev, dr); return 0; } EXPORT_SYMBOL_GPL(devm_gpio_request); /** * devm_gpio_request_one - request a single GPIO with initial setup * @dev: device to request for * @gpio: the GPIO number * @flags: GPIO configuration as specified by GPIOF_* * @label: a literal description string of this GPIO */ int devm_gpio_request_one(struct device *dev, unsigned gpio, unsigned long flags, const char *label) { unsigned *dr; int rc; dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL); if (!dr) return -ENOMEM; rc = gpio_request_one(gpio, flags, label); if (rc) { devres_free(dr); return rc; } *dr = gpio; devres_add(dev, dr); return 0; } EXPORT_SYMBOL_GPL(devm_gpio_request_one); static void devm_gpio_chip_release(void *data) { struct gpio_chip *gc = data; gpiochip_remove(gc); } /** * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key() * @dev: pointer to the device that gpio_chip belongs to. * @gc: the GPIO chip to register * @data: driver-private data associated with this chip * @lock_key: lockdep class for IRQ lock * @request_key: lockdep class for IRQ request * * Context: potentially before irqs will work * * The gpio chip automatically be released when the device is unbound. * * Returns: * A negative errno if the chip can't be registered, such as because the * gc->base is invalid or already associated with a different chip. * Otherwise it returns zero as a success code. */ int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc, void *data, struct lock_class_key *lock_key, struct lock_class_key *request_key) { int ret; ret = gpiochip_add_data_with_key(gc, data, lock_key, request_key); if (ret < 0) return ret; return devm_add_action_or_reset(dev, devm_gpio_chip_release, gc); } EXPORT_SYMBOL_GPL(devm_gpiochip_add_data_with_key);