include/linux/gpio.h

   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/errno.h>
  16
  17 /* see Documentation/driver-api/gpio/legacy.rst */
  18
  19 /* make these flag values available regardless of GPIO kconfig options */
  20 #define GPIOF_DIR_OUT   (0 << 0)
  21 #define GPIOF_DIR_IN    (1 << 0)
  22
  23 #define GPIOF_INIT_LOW  (0 << 1)
  24 #define GPIOF_INIT_HIGH (1 << 1)
  25
  26 #define GPIOF_IN                (GPIOF_DIR_IN)
  27 #define GPIOF_OUT_INIT_LOW      (GPIOF_DIR_OUT | GPIOF_INIT_LOW)
  28 #define GPIOF_OUT_INIT_HIGH     (GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
  29
  30 /* Gpio pin is active-low */
  31 #define GPIOF_ACTIVE_LOW        (1 << 2)
  32
  33 /* Gpio pin is open drain */
  34 #define GPIOF_OPEN_DRAIN        (1 << 3)
  35
  36 /* Gpio pin is open source */
  37 #define GPIOF_OPEN_SOURCE       (1 << 4)
  38
  39 #define GPIOF_EXPORT            (1 << 5)
  40 #define GPIOF_EXPORT_CHANGEABLE (1 << 6)
  41 #define GPIOF_EXPORT_DIR_FIXED  (GPIOF_EXPORT)
  42 #define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE)
  43
  44 /**
  45  * struct gpio - a structure describing a GPIO with configuration
  46  * @gpio:       the GPIO number
  47  * @flags:      GPIO configuration as specified by GPIOF_*
  48  * @label:      a literal description string of this GPIO
  49  */
  50 struct gpio {
  51         unsigned        gpio;
  52         unsigned long   flags;
  53         const char      *label;
  54 };
  55
  56 #ifdef CONFIG_GPIOLIB
  57
  58 #ifdef CONFIG_ARCH_HAVE_CUSTOM_GPIO_H
  59 #include <asm/gpio.h>
  60 #else
  61
  62 #include <asm-generic/gpio.h>
  63
  64 static inline int gpio_get_value(unsigned int gpio)
  65 {
  66         return __gpio_get_value(gpio);
  67 }
  68
  69 static inline void gpio_set_value(unsigned int gpio, int value)
  70 {
  71         __gpio_set_value(gpio, value);
  72 }
  73
  74 static inline int gpio_cansleep(unsigned int gpio)
  75 {
  76         return __gpio_cansleep(gpio);
  77 }
  78
  79 static inline int gpio_to_irq(unsigned int gpio)
  80 {
  81         return __gpio_to_irq(gpio);
  82 }
  83
  84 static inline int irq_to_gpio(unsigned int irq)
  85 {
  86         return -EINVAL;
  87 }
  88
  89 #endif /* ! CONFIG_ARCH_HAVE_CUSTOM_GPIO_H */
  90
  91 /* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */
  92
  93 struct device;
  94
  95 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label);
  96 int devm_gpio_request_one(struct device *dev, unsigned gpio,
  97                           unsigned long flags, const char *label);
  98 void devm_gpio_free(struct device *dev, unsigned int gpio);
  99
 100 #else /* ! CONFIG_GPIOLIB */
 101
 102 #include <linux/kernel.h>
 103 #include <linux/types.h>
 104 #include <linux/bug.h>
 105
 106 struct device;
 107 struct gpio_chip;
 108
 109 static inline bool gpio_is_valid(int number)
 110 {
 111         return false;
 112 }
 113
 114 static inline int gpio_request(unsigned gpio, const char *label)
 115 {
 116         return -ENOSYS;
 117 }
 118
 119 static inline int gpio_request_one(unsigned gpio,
 120                                         unsigned long flags, const char *label)
 121 {
 122         return -ENOSYS;
 123 }
 124
 125 static inline int gpio_request_array(const struct gpio *array, size_t num)
 126 {
 127         return -ENOSYS;
 128 }
 129
 130 static inline void gpio_free(unsigned gpio)
 131 {
 132         might_sleep();
 133
 134         /* GPIO can never have been requested */
 135         WARN_ON(1);
 136 }
 137
 138 static inline void gpio_free_array(const struct gpio *array, size_t num)
 139 {
 140         might_sleep();
 141
 142         /* GPIO can never have been requested */
 143         WARN_ON(1);
 144 }
 145
 146 static inline int gpio_direction_input(unsigned gpio)
 147 {
 148         return -ENOSYS;
 149 }
 150
 151 static inline int gpio_direction_output(unsigned gpio, int value)
 152 {
 153         return -ENOSYS;
 154 }
 155
 156 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
 157 {
 158         return -ENOSYS;
 159 }
 160
 161 static inline int gpio_get_value(unsigned gpio)
 162 {
 163         /* GPIO can never have been requested or set as {in,out}put */
 164         WARN_ON(1);
 165         return 0;
 166 }
 167
 168 static inline void gpio_set_value(unsigned gpio, int value)
 169 {
 170         /* GPIO can never have been requested or set as output */
 171         WARN_ON(1);
 172 }
 173
 174 static inline int gpio_cansleep(unsigned gpio)
 175 {
 176         /* GPIO can never have been requested or set as {in,out}put */
 177         WARN_ON(1);
 178         return 0;
 179 }
 180
 181 static inline int gpio_get_value_cansleep(unsigned gpio)
 182 {
 183         /* GPIO can never have been requested or set as {in,out}put */
 184         WARN_ON(1);
 185         return 0;
 186 }
 187
 188 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
 189 {
 190         /* GPIO can never have been requested or set as output */
 191         WARN_ON(1);
 192 }
 193
 194 static inline int gpio_export(unsigned gpio, bool direction_may_change)
 195 {
 196         /* GPIO can never have been requested or set as {in,out}put */
 197         WARN_ON(1);
 198         return -EINVAL;
 199 }
 200
 201 static inline int gpio_export_link(struct device *dev, const char *name,
 202                                 unsigned gpio)
 203 {
 204         /* GPIO can never have been exported */
 205         WARN_ON(1);
 206         return -EINVAL;
 207 }
 208
 209 static inline void gpio_unexport(unsigned gpio)
 210 {
 211         /* GPIO can never have been exported */
 212         WARN_ON(1);
 213 }
 214
 215 static inline int gpio_to_irq(unsigned gpio)
 216 {
 217         /* GPIO can never have been requested or set as input */
 218         WARN_ON(1);
 219         return -EINVAL;
 220 }
 221
 222 static inline int irq_to_gpio(unsigned irq)
 223 {
 224         /* irq can never have been returned from gpio_to_irq() */
 225         WARN_ON(1);
 226         return -EINVAL;
 227 }
 228
 229 static inline int devm_gpio_request(struct device *dev, unsigned gpio,
 230                                     const char *label)
 231 {
 232         WARN_ON(1);
 233         return -EINVAL;
 234 }
 235
 236 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
 237                                         unsigned long flags, const char *label)
 238 {
 239         WARN_ON(1);
 240         return -EINVAL;
 241 }
 242
 243 static inline void devm_gpio_free(struct device *dev, unsigned int gpio)
 244 {
 245         WARN_ON(1);
 246 }
 247
 248 #endif /* ! CONFIG_GPIOLIB */
 249
 250 #endif /* __LINUX_GPIO_H */