From 331758eef83620eef3f21289f0f44aba094d0503 Mon Sep 17 00:00:00 2001 From: Rojhalat Ibrahim Date: Wed, 11 Feb 2015 17:28:02 +0100 Subject: [PATCH] gpiolib: add devm_gpiod_get_array and devm_gpiod_put_array functions Add device managed variants of gpiod_get_array() / gpiod_put_array() functions for conveniently obtaining and disposing of an entire array of GPIOs with one function call. Signed-off-by: Rojhalat Ibrahim Reviewed-by: Alexandre Courbot Signed-off-by: Linus Walleij --- Documentation/gpio/consumer.txt | 14 +++++- drivers/gpio/devres.c | 89 +++++++++++++++++++++++++++++++++ include/linux/gpio/consumer.h | 30 +++++++++++ 3 files changed, 131 insertions(+), 2 deletions(-) diff --git a/Documentation/gpio/consumer.txt b/Documentation/gpio/consumer.txt index 2924f2ffcd91..d29a9725c9e5 100644 --- a/Documentation/gpio/consumer.txt +++ b/Documentation/gpio/consumer.txt @@ -102,11 +102,19 @@ Device-managed variants of these functions are also defined: const char *con_id, enum gpiod_flags flags) - struct gpio_desc * devm_gpiod_get_index_optional(struct device *dev, + struct gpio_desc *devm_gpiod_get_index_optional(struct device *dev, const char *con_id, unsigned int index, enum gpiod_flags flags) + struct gpio_descs *devm_gpiod_get_array(struct device *dev, + const char *con_id, + enum gpiod_flags flags) + + struct gpio_descs *devm_gpiod_get_array_optional(struct device *dev, + const char *con_id, + enum gpiod_flags flags) + A GPIO descriptor can be disposed of using the gpiod_put() function: void gpiod_put(struct gpio_desc *desc) @@ -119,10 +127,12 @@ It is strictly forbidden to use a descriptor after calling these functions. It is also not allowed to individually release descriptors (using gpiod_put()) from an array acquired with gpiod_get_array(). -The device-managed variant is, unsurprisingly: +The device-managed variants are, unsurprisingly: void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) + void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs) + Using GPIOs =========== diff --git a/drivers/gpio/devres.c b/drivers/gpio/devres.c index 12c2082f968e..ec24da2418b3 100644 --- a/drivers/gpio/devres.c +++ b/drivers/gpio/devres.c @@ -35,6 +35,20 @@ static int devm_gpiod_match(struct device *dev, void *res, void *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 @@ -185,6 +199,66 @@ struct gpio_desc *__must_check __devm_gpiod_get_index_optional(struct device *de } EXPORT_SYMBOL(__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(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 (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) + return NULL; + + return descs; +} +EXPORT_SYMBOL(devm_gpiod_get_array_optional); + /** * devm_gpiod_put - Resource-managed gpiod_put() * @desc: GPIO descriptor to dispose of @@ -200,6 +274,21 @@ void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) } EXPORT_SYMBOL(devm_gpiod_put); +/** + * devm_gpiod_put_array - Resource-managed gpiod_put_array() + * @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(devm_gpiod_put_array); + diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h index 33eb52fd0932..3a7c9ffd5ab9 100644 --- a/include/linux/gpio/consumer.h +++ b/include/linux/gpio/consumer.h @@ -83,7 +83,14 @@ struct gpio_desc *__must_check __devm_gpiod_get_optional(struct device *dev, 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_descs *__must_check devm_gpiod_get_array(struct device *dev, + const char *con_id, + enum gpiod_flags flags); +struct gpio_descs *__must_check +devm_gpiod_get_array_optional(struct device *dev, const char *con_id, + enum gpiod_flags flags); void devm_gpiod_put(struct device *dev, struct gpio_desc *desc); +void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs); int gpiod_get_direction(struct gpio_desc *desc); int gpiod_direction_input(struct gpio_desc *desc); @@ -228,6 +235,20 @@ __devm_gpiod_get_index_optional(struct device *dev, const char *con_id, return ERR_PTR(-ENOSYS); } +static inline struct gpio_descs *__must_check +devm_gpiod_get_array(struct device *dev, const char *con_id, + enum gpiod_flags flags) +{ + return ERR_PTR(-ENOSYS); +} + +static inline struct gpio_descs *__must_check +devm_gpiod_get_array_optional(struct device *dev, const char *con_id, + enum gpiod_flags flags) +{ + return ERR_PTR(-ENOSYS); +} + static inline void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) { might_sleep(); @@ -236,6 +257,15 @@ static inline void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) WARN_ON(1); } +static inline void devm_gpiod_put_array(struct device *dev, + struct gpio_descs *descs) +{ + might_sleep(); + + /* GPIO can never have been requested */ + WARN_ON(1); +} + static inline int gpiod_get_direction(const struct gpio_desc *desc) { -- 2.34.1