diff options
Diffstat (limited to 'drivers/gpio/devres.c')
| -rw-r--r-- | drivers/gpio/devres.c | 175 |
1 files changed, 166 insertions, 9 deletions
diff --git a/drivers/gpio/devres.c b/drivers/gpio/devres.c index 3dd29399cef..65978cf85f7 100644 --- a/drivers/gpio/devres.c +++ b/drivers/gpio/devres.c @@ -15,10 +15,138 @@ */ #include <linux/module.h> +#include <linux/err.h> #include <linux/gpio.h> +#include <linux/gpio/consumer.h> #include <linux/device.h> #include <linux/gfp.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; +} + +/** + * devm_gpiod_get - Resource-managed gpiod_get() + * @dev: GPIO consumer + * @con_id: function within the GPIO consumer + * + * 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) +{ + return devm_gpiod_get_index(dev, con_id, 0); +} +EXPORT_SYMBOL(devm_gpiod_get); + +/** + * devm_gpiod_get_optional - Resource-managed gpiod_get_optional() + * @dev: GPIO consumer + * @con_id: function within the GPIO consumer + * + * 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) +{ + return devm_gpiod_get_index_optional(dev, con_id, 0); +} +EXPORT_SYMBOL(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 + * + * 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) +{ + struct gpio_desc **dr; + struct gpio_desc *desc; + + dr = devres_alloc(devm_gpiod_release, sizeof(struct gpiod_desc *), + GFP_KERNEL); + if (!dr) + return ERR_PTR(-ENOMEM); + + desc = gpiod_get_index(dev, con_id, idx); + if (IS_ERR(desc)) { + devres_free(dr); + return desc; + } + + *dr = desc; + devres_add(dev, dr); + + return desc; +} +EXPORT_SYMBOL(devm_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 + * + * 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) +{ + struct gpio_desc *desc; + + desc = devm_gpiod_get_index(dev, con_id, index); + if (IS_ERR(desc)) { + if (PTR_ERR(desc) == -ENOENT) + return NULL; + } + + return desc; +} +EXPORT_SYMBOL(devm_gpiod_get_index_optional); + +/** + * devm_gpiod_put - Resource-managed gpiod_put() + * @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(devm_gpiod_put); + + + + static void devm_gpio_release(struct device *dev, void *res) { unsigned *gpio = res; @@ -34,10 +162,10 @@ static int devm_gpio_match(struct device *dev, void *res, void *data) } /** - * 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 + * 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 @@ -71,9 +199,39 @@ int devm_gpio_request(struct device *dev, unsigned gpio, const char *label) EXPORT_SYMBOL(devm_gpio_request); /** - * devm_gpio_free - free an interrupt - * @dev: device to free gpio for - * @gpio: gpio to free + * 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(devm_gpio_request_one); + +/** + * devm_gpio_free - free a GPIO + * @dev: device to free GPIO for + * @gpio: GPIO to free * * Except for the extra @dev argument, this function takes the * same arguments and performs the same function as gpio_free(). @@ -83,8 +241,7 @@ EXPORT_SYMBOL(devm_gpio_request); void devm_gpio_free(struct device *dev, unsigned int gpio) { - WARN_ON(devres_destroy(dev, devm_gpio_release, devm_gpio_match, + WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match, &gpio)); - gpio_free(gpio); } EXPORT_SYMBOL(devm_gpio_free); |