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 int gpio_request_array(const struct gpio *array, size_t num); 118 void gpio_free_array(const struct gpio *array, size_t num); 119 120 /* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */ 121 122 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label); 123 int 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> 132 133 static inline bool gpio_is_valid(int number) 134 { 135 return false; 136 } 137 138 static inline int gpio_request(unsigned gpio, const char *label) 139 { 140 return -ENOSYS; 141 } 142 143 static inline int gpio_request_one(unsigned gpio, 144 unsigned long flags, const char *label) 145 { 146 return -ENOSYS; 147 } 148 149 static inline int gpio_request_array(const struct gpio *array, size_t num) 150 { 151 return -ENOSYS; 152 } 153 154 static inline void gpio_free(unsigned gpio) 155 { 156 might_sleep(); 157 158 /* GPIO can never have been requested */ 159 WARN_ON(1); 160 } 161 162 static 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 } 169 170 static inline int gpio_direction_input(unsigned gpio) 171 { 172 return -ENOSYS; 173 } 174 175 static inline int gpio_direction_output(unsigned gpio, int value) 176 { 177 return -ENOSYS; 178 } 179 180 static 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 } 186 187 static 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 } 192 193 static 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 } 199 200 static 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 } 205 206 static 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 } 212 213 static inline int devm_gpio_request(struct device *dev, unsigned gpio, 214 const char *label) 215 { 216 WARN_ON(1); 217 return -EINVAL; 218 } 219 220 static 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