1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * <linux/gpio.h> 4 * 5 * This is the LEGACY GPIO bulk include file, including legacy APIs. It is 6 * used for GPIO drivers still referencing the global GPIO numberspace, 7 * and should not be included in new code. 8 * 9 * If you're implementing a GPIO driver, only include <linux/gpio/driver.h> 10 * If you're implementing a GPIO consumer, only include <linux/gpio/consumer.h> 11 */ 12#ifndef __LINUX_GPIO_H 13#define __LINUX_GPIO_H 14 15#include <linux/types.h> 16 17struct device; 18 19/* see Documentation/driver-api/gpio/legacy.rst */ 20 21/* make these flag values available regardless of GPIO kconfig options */ 22#define GPIOF_DIR_OUT (0 << 0) 23#define GPIOF_DIR_IN (1 << 0) 24 25#define GPIOF_INIT_LOW (0 << 1) 26#define GPIOF_INIT_HIGH (1 << 1) 27 28#define GPIOF_IN (GPIOF_DIR_IN) 29#define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW) 30#define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH) 31 32/* Gpio pin is active-low */ 33#define GPIOF_ACTIVE_LOW (1 << 2) 34 35/** 36 * struct gpio - a structure describing a GPIO with configuration 37 * @gpio: the GPIO number 38 * @flags: GPIO configuration as specified by GPIOF_* 39 * @label: a literal description string of this GPIO 40 */ 41struct gpio { 42 unsigned gpio; 43 unsigned long flags; 44 const char *label; 45}; 46 47#ifdef CONFIG_GPIOLIB 48 49#include <linux/gpio/consumer.h> 50 51/* 52 * "valid" GPIO numbers are nonnegative and may be passed to 53 * setup routines like gpio_request(). Only some valid numbers 54 * can successfully be requested and used. 55 * 56 * Invalid GPIO numbers are useful for indicating no-such-GPIO in 57 * platform data and other tables. 58 */ 59static inline bool gpio_is_valid(int number) 60{ 61 /* only non-negative numbers are valid */ 62 return number >= 0; 63} 64 65/* 66 * Platforms may implement their GPIO interface with library code, 67 * at a small performance cost for non-inlined operations and some 68 * extra memory (for code and for per-GPIO table entries). 69 */ 70 71/* 72 * At the end we want all GPIOs to be dynamically allocated from 0. 73 * However, some legacy drivers still perform fixed allocation. 74 * Until they are all fixed, leave 0-512 space for them. 75 */ 76#define GPIO_DYNAMIC_BASE 512 77 78/* Always use the library code for GPIO management calls, 79 * or when sleeping may be involved. 80 */ 81int gpio_request(unsigned gpio, const char *label); 82void gpio_free(unsigned gpio); 83 84static inline int gpio_direction_input(unsigned gpio) 85{ 86 return gpiod_direction_input(gpio_to_desc(gpio)); 87} 88static inline int gpio_direction_output(unsigned gpio, int value) 89{ 90 return gpiod_direction_output_raw(gpio_to_desc(gpio), value); 91} 92 93static inline int gpio_get_value_cansleep(unsigned gpio) 94{ 95 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio)); 96} 97static inline void gpio_set_value_cansleep(unsigned gpio, int value) 98{ 99 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value); 100} 101 102static inline int gpio_get_value(unsigned gpio) 103{ 104 return gpiod_get_raw_value(gpio_to_desc(gpio)); 105} 106static inline void gpio_set_value(unsigned gpio, int value) 107{ 108 return gpiod_set_raw_value(gpio_to_desc(gpio), value); 109} 110 111static inline int gpio_to_irq(unsigned gpio) 112{ 113 return gpiod_to_irq(gpio_to_desc(gpio)); 114} 115 116int gpio_request_one(unsigned gpio, unsigned long flags, const char *label); 117int gpio_request_array(const struct gpio *array, size_t num); 118void gpio_free_array(const struct gpio *array, size_t num); 119 120/* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */ 121 122int devm_gpio_request(struct device *dev, unsigned gpio, const char *label); 123int devm_gpio_request_one(struct device *dev, unsigned gpio, 124 unsigned long flags, const char *label); 125 126#else /* ! CONFIG_GPIOLIB */ 127 128#include <linux/kernel.h> 129 130#include <asm/bug.h> 131#include <asm/errno.h> 132 133static inline bool gpio_is_valid(int number) 134{ 135 return false; 136} 137 138static inline int gpio_request(unsigned gpio, const char *label) 139{ 140 return -ENOSYS; 141} 142 143static inline int gpio_request_one(unsigned gpio, 144 unsigned long flags, const char *label) 145{ 146 return -ENOSYS; 147} 148 149static inline int gpio_request_array(const struct gpio *array, size_t num) 150{ 151 return -ENOSYS; 152} 153 154static inline void gpio_free(unsigned gpio) 155{ 156 might_sleep(); 157 158 /* GPIO can never have been requested */ 159 WARN_ON(1); 160} 161 162static inline void gpio_free_array(const struct gpio *array, size_t num) 163{ 164 might_sleep(); 165 166 /* GPIO can never have been requested */ 167 WARN_ON(1); 168} 169 170static inline int gpio_direction_input(unsigned gpio) 171{ 172 return -ENOSYS; 173} 174 175static inline int gpio_direction_output(unsigned gpio, int value) 176{ 177 return -ENOSYS; 178} 179 180static inline int gpio_get_value(unsigned gpio) 181{ 182 /* GPIO can never have been requested or set as {in,out}put */ 183 WARN_ON(1); 184 return 0; 185} 186 187static inline void gpio_set_value(unsigned gpio, int value) 188{ 189 /* GPIO can never have been requested or set as output */ 190 WARN_ON(1); 191} 192 193static inline int gpio_get_value_cansleep(unsigned gpio) 194{ 195 /* GPIO can never have been requested or set as {in,out}put */ 196 WARN_ON(1); 197 return 0; 198} 199 200static inline void gpio_set_value_cansleep(unsigned gpio, int value) 201{ 202 /* GPIO can never have been requested or set as output */ 203 WARN_ON(1); 204} 205 206static inline int gpio_to_irq(unsigned gpio) 207{ 208 /* GPIO can never have been requested or set as input */ 209 WARN_ON(1); 210 return -EINVAL; 211} 212 213static inline int devm_gpio_request(struct device *dev, unsigned gpio, 214 const char *label) 215{ 216 WARN_ON(1); 217 return -EINVAL; 218} 219 220static inline int devm_gpio_request_one(struct device *dev, unsigned gpio, 221 unsigned long flags, const char *label) 222{ 223 WARN_ON(1); 224 return -EINVAL; 225} 226 227#endif /* ! CONFIG_GPIOLIB */ 228 229#endif /* __LINUX_GPIO_H */ 230