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 #define GPIOF_EXPORT (1 << 5) 42 #define GPIOF_EXPORT_CHANGEABLE (1 << 6) 43 #define GPIOF_EXPORT_DIR_FIXED (GPIOF_EXPORT) 44 #define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE) 45 46 /** 47 * struct gpio - a structure describing a GPIO with configuration 48 * @gpio: the GPIO number 49 * @flags: GPIO configuration as specified by GPIOF_* 50 * @label: a literal description string of this GPIO 51 */ 52 struct gpio { 53 unsigned gpio; 54 unsigned long flags; 55 const char *label; 56 }; 57 58 #ifdef CONFIG_GPIOLIB 59 60 #include <linux/gpio/consumer.h> 61 62 /* 63 * "valid" GPIO numbers are nonnegative and may be passed to 64 * setup routines like gpio_request(). Only some valid numbers 65 * can successfully be requested and used. 66 * 67 * Invalid GPIO numbers are useful for indicating no-such-GPIO in 68 * platform data and other tables. 69 */ 70 static inline bool gpio_is_valid(int number) 71 { 72 /* only non-negative numbers are valid */ 73 return number >= 0; 74 } 75 76 /* 77 * Platforms may implement their GPIO interface with library code, 78 * at a small performance cost for non-inlined operations and some 79 * extra memory (for code and for per-GPIO table entries). 80 */ 81 82 /* 83 * At the end we want all GPIOs to be dynamically allocated from 0. 84 * However, some legacy drivers still perform fixed allocation. 85 * Until they are all fixed, leave 0-512 space for them. 86 */ 87 #define GPIO_DYNAMIC_BASE 512 88 89 /* Always use the library code for GPIO management calls, 90 * or when sleeping may be involved. 91 */ 92 int gpio_request(unsigned gpio, const char *label); 93 void gpio_free(unsigned gpio); 94 95 static inline int gpio_direction_input(unsigned gpio) 96 { 97 return gpiod_direction_input(gpio_to_desc(gpio)); 98 } 99 static inline int gpio_direction_output(unsigned gpio, int value) 100 { 101 return gpiod_direction_output_raw(gpio_to_desc(gpio), value); 102 } 103 104 static inline int gpio_get_value_cansleep(unsigned gpio) 105 { 106 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio)); 107 } 108 static inline void gpio_set_value_cansleep(unsigned gpio, int value) 109 { 110 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value); 111 } 112 113 static inline int gpio_get_value(unsigned gpio) 114 { 115 return gpiod_get_raw_value(gpio_to_desc(gpio)); 116 } 117 static inline void gpio_set_value(unsigned gpio, int value) 118 { 119 return gpiod_set_raw_value(gpio_to_desc(gpio), value); 120 } 121 122 static inline int gpio_cansleep(unsigned gpio) 123 { 124 return gpiod_cansleep(gpio_to_desc(gpio)); 125 } 126 127 static inline int gpio_to_irq(unsigned gpio) 128 { 129 return gpiod_to_irq(gpio_to_desc(gpio)); 130 } 131 132 int gpio_request_one(unsigned gpio, unsigned long flags, const char *label); 133 int gpio_request_array(const struct gpio *array, size_t num); 134 void gpio_free_array(const struct gpio *array, size_t num); 135 136 /* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */ 137 138 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label); 139 int devm_gpio_request_one(struct device *dev, unsigned gpio, 140 unsigned long flags, const char *label); 141 142 #else /* ! CONFIG_GPIOLIB */ 143 144 #include <linux/kernel.h> 145 146 #include <asm/bug.h> 147 #include <asm/errno.h> 148 149 static inline bool gpio_is_valid(int number) 150 { 151 return false; 152 } 153 154 static inline int gpio_request(unsigned gpio, const char *label) 155 { 156 return -ENOSYS; 157 } 158 159 static inline int gpio_request_one(unsigned gpio, 160 unsigned long flags, const char *label) 161 { 162 return -ENOSYS; 163 } 164 165 static inline int gpio_request_array(const struct gpio *array, size_t num) 166 { 167 return -ENOSYS; 168 } 169 170 static inline void gpio_free(unsigned gpio) 171 { 172 might_sleep(); 173 174 /* GPIO can never have been requested */ 175 WARN_ON(1); 176 } 177 178 static inline void gpio_free_array(const struct gpio *array, size_t num) 179 { 180 might_sleep(); 181 182 /* GPIO can never have been requested */ 183 WARN_ON(1); 184 } 185 186 static inline int gpio_direction_input(unsigned gpio) 187 { 188 return -ENOSYS; 189 } 190 191 static inline int gpio_direction_output(unsigned gpio, int value) 192 { 193 return -ENOSYS; 194 } 195 196 static inline int gpio_get_value(unsigned gpio) 197 { 198 /* GPIO can never have been requested or set as {in,out}put */ 199 WARN_ON(1); 200 return 0; 201 } 202 203 static inline void gpio_set_value(unsigned gpio, int value) 204 { 205 /* GPIO can never have been requested or set as output */ 206 WARN_ON(1); 207 } 208 209 static inline int gpio_cansleep(unsigned gpio) 210 { 211 /* GPIO can never have been requested or set as {in,out}put */ 212 WARN_ON(1); 213 return 0; 214 } 215 216 static inline int gpio_get_value_cansleep(unsigned gpio) 217 { 218 /* GPIO can never have been requested or set as {in,out}put */ 219 WARN_ON(1); 220 return 0; 221 } 222 223 static inline void gpio_set_value_cansleep(unsigned gpio, int value) 224 { 225 /* GPIO can never have been requested or set as output */ 226 WARN_ON(1); 227 } 228 229 static inline int gpio_to_irq(unsigned gpio) 230 { 231 /* GPIO can never have been requested or set as input */ 232 WARN_ON(1); 233 return -EINVAL; 234 } 235 236 static inline int devm_gpio_request(struct device *dev, unsigned gpio, 237 const char *label) 238 { 239 WARN_ON(1); 240 return -EINVAL; 241 } 242 243 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio, 244 unsigned long flags, const char *label) 245 { 246 WARN_ON(1); 247 return -EINVAL; 248 } 249 250 #endif /* ! CONFIG_GPIOLIB */ 251 252 #endif /* __LINUX_GPIO_H */ 253