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 17 struct 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 */ 41 struct 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 */ 59 static 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 */ 81 int gpio_request(unsigned gpio, const char *label); 82 void gpio_free(unsigned gpio); 83 84 static inline int gpio_direction_input(unsigned gpio) 85 { 86 return gpiod_direction_input(gpio_to_desc(gpio)); 87 } 88 static inline int gpio_direction_output(unsigned gpio, int value) 89 { 90 return gpiod_direction_output_raw(gpio_to_desc(gpio), value); 91 } 92 93 static inline int gpio_get_value_cansleep(unsigned gpio) 94 { 95 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio)); 96 } 97 static inline void gpio_set_value_cansleep(unsigned gpio, int value) 98 { 99 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value); 100 } 101 102 static inline int gpio_get_value(unsigned gpio) 103 { 104 return gpiod_get_raw_value(gpio_to_desc(gpio)); 105 } 106 static inline void gpio_set_value(unsigned gpio, int value) 107 { 108 return gpiod_set_raw_value(gpio_to_desc(gpio), value); 109 } 110 111 static inline int gpio_to_irq(unsigned gpio) 112 { 113 return gpiod_to_irq(gpio_to_desc(gpio)); 114 } 115 116 int gpio_request_one(unsigned gpio, unsigned long flags, const char *label); 117 118 /* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */ 119 120 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label); 121 int devm_gpio_request_one(struct device *dev, unsigned gpio, 122 unsigned long flags, const char *label); 123 124 #else /* ! CONFIG_GPIOLIB */ 125 126 #include <linux/kernel.h> 127 128 #include <asm/bug.h> 129 #include <asm/errno.h> 130 131 static inline bool gpio_is_valid(int number) 132 { 133 return false; 134 } 135 136 static inline int gpio_request(unsigned gpio, const char *label) 137 { 138 return -ENOSYS; 139 } 140 141 static inline int gpio_request_one(unsigned gpio, 142 unsigned long flags, const char *label) 143 { 144 return -ENOSYS; 145 } 146 147 static inline void gpio_free(unsigned gpio) 148 { 149 might_sleep(); 150 151 /* GPIO can never have been requested */ 152 WARN_ON(1); 153 } 154 155 static inline int gpio_direction_input(unsigned gpio) 156 { 157 return -ENOSYS; 158 } 159 160 static inline int gpio_direction_output(unsigned gpio, int value) 161 { 162 return -ENOSYS; 163 } 164 165 static inline int gpio_get_value(unsigned gpio) 166 { 167 /* GPIO can never have been requested or set as {in,out}put */ 168 WARN_ON(1); 169 return 0; 170 } 171 172 static inline void gpio_set_value(unsigned gpio, int value) 173 { 174 /* GPIO can never have been requested or set as output */ 175 WARN_ON(1); 176 } 177 178 static inline int gpio_get_value_cansleep(unsigned gpio) 179 { 180 /* GPIO can never have been requested or set as {in,out}put */ 181 WARN_ON(1); 182 return 0; 183 } 184 185 static inline void gpio_set_value_cansleep(unsigned gpio, int value) 186 { 187 /* GPIO can never have been requested or set as output */ 188 WARN_ON(1); 189 } 190 191 static inline int gpio_to_irq(unsigned gpio) 192 { 193 /* GPIO can never have been requested or set as input */ 194 WARN_ON(1); 195 return -EINVAL; 196 } 197 198 static inline int devm_gpio_request(struct device *dev, unsigned gpio, 199 const char *label) 200 { 201 WARN_ON(1); 202 return -EINVAL; 203 } 204 205 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio, 206 unsigned long flags, const char *label) 207 { 208 WARN_ON(1); 209 return -EINVAL; 210 } 211 212 #endif /* ! CONFIG_GPIOLIB */ 213 214 #endif /* __LINUX_GPIO_H */ 215