diff options
Diffstat (limited to 'include/linux/gpio.h')
| -rw-r--r-- | include/linux/gpio.h | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/include/linux/gpio.h b/include/linux/gpio.h new file mode 100644 index 000000000..7ecc25c54 --- /dev/null +++ b/include/linux/gpio.h @@ -0,0 +1,229 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * <linux/gpio.h> + * + * This is the LEGACY GPIO bulk include file, including legacy APIs. It is + * used for GPIO drivers still referencing the global GPIO numberspace, + * and should not be included in new code. + * + * If you're implementing a GPIO driver, only include <linux/gpio/driver.h> + * If you're implementing a GPIO consumer, only include <linux/gpio/consumer.h> + */ +#ifndef __LINUX_GPIO_H +#define __LINUX_GPIO_H + +#include <linux/types.h> + +struct device; + +/* see Documentation/driver-api/gpio/legacy.rst */ + +/* make these flag values available regardless of GPIO kconfig options */ +#define GPIOF_DIR_OUT (0 << 0) +#define GPIOF_DIR_IN (1 << 0) + +#define GPIOF_INIT_LOW (0 << 1) +#define GPIOF_INIT_HIGH (1 << 1) + +#define GPIOF_IN (GPIOF_DIR_IN) +#define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW) +#define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH) + +/* Gpio pin is active-low */ +#define GPIOF_ACTIVE_LOW (1 << 2) + +/** + * struct gpio - a structure describing a GPIO with configuration + * @gpio: the GPIO number + * @flags: GPIO configuration as specified by GPIOF_* + * @label: a literal description string of this GPIO + */ +struct gpio { + unsigned gpio; + unsigned long flags; + const char *label; +}; + +#ifdef CONFIG_GPIOLIB + +#include <linux/gpio/consumer.h> + +/* + * "valid" GPIO numbers are nonnegative and may be passed to + * setup routines like gpio_request(). Only some valid numbers + * can successfully be requested and used. + * + * Invalid GPIO numbers are useful for indicating no-such-GPIO in + * platform data and other tables. + */ +static inline bool gpio_is_valid(int number) +{ + /* only non-negative numbers are valid */ + return number >= 0; +} + +/* + * Platforms may implement their GPIO interface with library code, + * at a small performance cost for non-inlined operations and some + * extra memory (for code and for per-GPIO table entries). + */ + +/* + * At the end we want all GPIOs to be dynamically allocated from 0. + * However, some legacy drivers still perform fixed allocation. + * Until they are all fixed, leave 0-512 space for them. + */ +#define GPIO_DYNAMIC_BASE 512 + +/* Always use the library code for GPIO management calls, + * or when sleeping may be involved. + */ +int gpio_request(unsigned gpio, const char *label); +void gpio_free(unsigned gpio); + +static inline int gpio_direction_input(unsigned gpio) +{ + return gpiod_direction_input(gpio_to_desc(gpio)); +} +static inline int gpio_direction_output(unsigned gpio, int value) +{ + return gpiod_direction_output_raw(gpio_to_desc(gpio), value); +} + +static inline int gpio_get_value_cansleep(unsigned gpio) +{ + return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio)); +} +static inline void gpio_set_value_cansleep(unsigned gpio, int value) +{ + return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value); +} + +static inline int gpio_get_value(unsigned gpio) +{ + return gpiod_get_raw_value(gpio_to_desc(gpio)); +} +static inline void gpio_set_value(unsigned gpio, int value) +{ + return gpiod_set_raw_value(gpio_to_desc(gpio), value); +} + +static inline int gpio_to_irq(unsigned gpio) +{ + return gpiod_to_irq(gpio_to_desc(gpio)); +} + +int gpio_request_one(unsigned gpio, unsigned long flags, const char *label); +int gpio_request_array(const struct gpio *array, size_t num); +void gpio_free_array(const struct gpio *array, size_t num); + +/* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */ + +int devm_gpio_request(struct device *dev, unsigned gpio, const char *label); +int devm_gpio_request_one(struct device *dev, unsigned gpio, + unsigned long flags, const char *label); + +#else /* ! CONFIG_GPIOLIB */ + +#include <linux/kernel.h> + +#include <asm/bug.h> +#include <asm/errno.h> + +static inline bool gpio_is_valid(int number) +{ + return false; +} + +static inline int gpio_request(unsigned gpio, const char *label) +{ + return -ENOSYS; +} + +static inline int gpio_request_one(unsigned gpio, + unsigned long flags, const char *label) +{ + return -ENOSYS; +} + +static inline int gpio_request_array(const struct gpio *array, size_t num) +{ + return -ENOSYS; +} + +static inline void gpio_free(unsigned gpio) +{ + might_sleep(); + + /* GPIO can never have been requested */ + WARN_ON(1); +} + +static inline void gpio_free_array(const struct gpio *array, size_t num) +{ + might_sleep(); + + /* GPIO can never have been requested */ + WARN_ON(1); +} + +static inline int gpio_direction_input(unsigned gpio) +{ + return -ENOSYS; +} + +static inline int gpio_direction_output(unsigned gpio, int value) +{ + return -ENOSYS; +} + +static inline int gpio_get_value(unsigned gpio) +{ + /* GPIO can never have been requested or set as {in,out}put */ + WARN_ON(1); + return 0; +} + +static inline void gpio_set_value(unsigned gpio, int value) +{ + /* GPIO can never have been requested or set as output */ + WARN_ON(1); +} + +static inline int gpio_get_value_cansleep(unsigned gpio) +{ + /* GPIO can never have been requested or set as {in,out}put */ + WARN_ON(1); + return 0; +} + +static inline void gpio_set_value_cansleep(unsigned gpio, int value) +{ + /* GPIO can never have been requested or set as output */ + WARN_ON(1); +} + +static inline int gpio_to_irq(unsigned gpio) +{ + /* GPIO can never have been requested or set as input */ + WARN_ON(1); + return -EINVAL; +} + +static inline int devm_gpio_request(struct device *dev, unsigned gpio, + const char *label) +{ + WARN_ON(1); + return -EINVAL; +} + +static inline int devm_gpio_request_one(struct device *dev, unsigned gpio, + unsigned long flags, const char *label) +{ + WARN_ON(1); + return -EINVAL; +} + +#endif /* ! CONFIG_GPIOLIB */ + +#endif /* __LINUX_GPIO_H */ |