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 /* Gpio pin is open drain */ 36 #define GPIOF_OPEN_DRAIN (1 << 3) 37 38 /* Gpio pin is open source */ 39 #define GPIOF_OPEN_SOURCE (1 << 4) 40 41 /** 42 * struct gpio - a structure describing a GPIO with configuration 43 * @gpio: the GPIO number 44 * @flags: GPIO configuration as specified by GPIOF_* 45 * @label: a literal description string of this GPIO 46 */ 47 struct gpio { 48 unsigned gpio; 49 unsigned long flags; 50 const char *label; 51 }; 52 53 #ifdef CONFIG_GPIOLIB 54 55 #include <linux/gpio/consumer.h> 56 57 /* 58 * "valid" GPIO numbers are nonnegative and may be passed to 59 * setup routines like gpio_request(). Only some valid numbers 60 * can successfully be requested and used. 61 * 62 * Invalid GPIO numbers are useful for indicating no-such-GPIO in 63 * platform data and other tables. 64 */ 65 static inline bool gpio_is_valid(int number) 66 { 67 /* only non-negative numbers are valid */ 68 return number >= 0; 69 } 70 71 /* 72 * Platforms may implement their GPIO interface with library code, 73 * at a small performance cost for non-inlined operations and some 74 * extra memory (for code and for per-GPIO table entries). 75 */ 76 77 /* 78 * At the end we want all GPIOs to be dynamically allocated from 0. 79 * However, some legacy drivers still perform fixed allocation. 80 * Until they are all fixed, leave 0-512 space for them. 81 */ 82 #define GPIO_DYNAMIC_BASE 512 83 84 /* Always use the library code for GPIO management calls, 85 * or when sleeping may be involved. 86 */ 87 int gpio_request(unsigned gpio, const char *label); 88 void gpio_free(unsigned gpio); 89 90 static inline int gpio_direction_input(unsigned gpio) 91 { 92 return gpiod_direction_input(gpio_to_desc(gpio)); 93 } 94 static inline int gpio_direction_output(unsigned gpio, int value) 95 { 96 return gpiod_direction_output_raw(gpio_to_desc(gpio), value); 97 } 98 99 static inline int gpio_get_value_cansleep(unsigned gpio) 100 { 101 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio)); 102 } 103 static inline void gpio_set_value_cansleep(unsigned gpio, int value) 104 { 105 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value); 106 } 107 108 static inline int gpio_get_value(unsigned gpio) 109 { 110 return gpiod_get_raw_value(gpio_to_desc(gpio)); 111 } 112 static inline void gpio_set_value(unsigned gpio, int value) 113 { 114 return gpiod_set_raw_value(gpio_to_desc(gpio), value); 115 } 116 117 static inline int gpio_cansleep(unsigned gpio) 118 { 119 return gpiod_cansleep(gpio_to_desc(gpio)); 120 } 121 122 static inline int gpio_to_irq(unsigned gpio) 123 { 124 return gpiod_to_irq(gpio_to_desc(gpio)); 125 } 126 127 int gpio_request_one(unsigned gpio, unsigned long flags, const char *label); 128 int gpio_request_array(const struct gpio *array, size_t num); 129 void gpio_free_array(const struct gpio *array, size_t num); 130 131 /* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */ 132 133 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label); 134 int devm_gpio_request_one(struct device *dev, unsigned gpio, 135 unsigned long flags, const char *label); 136 137 #else /* ! CONFIG_GPIOLIB */ 138 139 #include <linux/kernel.h> 140 141 #include <asm/bug.h> 142 #include <asm/errno.h> 143 144 static inline bool gpio_is_valid(int number) 145 { 146 return false; 147 } 148 149 static inline int gpio_request(unsigned gpio, const char *label) 150 { 151 return -ENOSYS; 152 } 153 154 static inline int gpio_request_one(unsigned gpio, 155 unsigned long flags, const char *label) 156 { 157 return -ENOSYS; 158 } 159 160 static inline int gpio_request_array(const struct gpio *array, size_t num) 161 { 162 return -ENOSYS; 163 } 164 165 static inline void gpio_free(unsigned gpio) 166 { 167 might_sleep(); 168 169 /* GPIO can never have been requested */ 170 WARN_ON(1); 171 } 172 173 static inline void gpio_free_array(const struct gpio *array, size_t num) 174 { 175 might_sleep(); 176 177 /* GPIO can never have been requested */ 178 WARN_ON(1); 179 } 180 181 static inline int gpio_direction_input(unsigned gpio) 182 { 183 return -ENOSYS; 184 } 185 186 static inline int gpio_direction_output(unsigned gpio, int value) 187 { 188 return -ENOSYS; 189 } 190 191 static inline int gpio_get_value(unsigned gpio) 192 { 193 /* GPIO can never have been requested or set as {in,out}put */ 194 WARN_ON(1); 195 return 0; 196 } 197 198 static inline void gpio_set_value(unsigned gpio, int value) 199 { 200 /* GPIO can never have been requested or set as output */ 201 WARN_ON(1); 202 } 203 204 static inline int gpio_cansleep(unsigned gpio) 205 { 206 /* GPIO can never have been requested or set as {in,out}put */ 207 WARN_ON(1); 208 return 0; 209 } 210 211 static inline int gpio_get_value_cansleep(unsigned gpio) 212 { 213 /* GPIO can never have been requested or set as {in,out}put */ 214 WARN_ON(1); 215 return 0; 216 } 217 218 static inline void gpio_set_value_cansleep(unsigned gpio, int value) 219 { 220 /* GPIO can never have been requested or set as output */ 221 WARN_ON(1); 222 } 223 224 static inline int gpio_to_irq(unsigned gpio) 225 { 226 /* GPIO can never have been requested or set as input */ 227 WARN_ON(1); 228 return -EINVAL; 229 } 230 231 static inline int devm_gpio_request(struct device *dev, unsigned gpio, 232 const char *label) 233 { 234 WARN_ON(1); 235 return -EINVAL; 236 } 237 238 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio, 239 unsigned long flags, const char *label) 240 { 241 WARN_ON(1); 242 return -EINVAL; 243 } 244 245 #endif /* ! CONFIG_GPIOLIB */ 246 247 #endif /* __LINUX_GPIO_H */ 248