include/linux/gpio.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * <linux/gpio.h>
0004  *
0005  * This is the LEGACY GPIO bulk include file, including legacy APIs. It is
0006  * used for GPIO drivers still referencing the global GPIO numberspace,
0007  * and should not be included in new code.
0008  *
0009  * If you're implementing a GPIO driver, only include <linux/gpio/driver.h>
0010  * If you're implementing a GPIO consumer, only include <linux/gpio/consumer.h>
0011  */
0012 #ifndef __LINUX_GPIO_H
0013 #define __LINUX_GPIO_H
0014
0015 #include <linux/errno.h>
0016
0017 /* see Documentation/driver-api/gpio/legacy.rst */
0018
0019 /* make these flag values available regardless of GPIO kconfig options */
0020 #define GPIOF_DIR_OUT   (0 << 0)
0021 #define GPIOF_DIR_IN    (1 << 0)
0022
0023 #define GPIOF_INIT_LOW  (0 << 1)
0024 #define GPIOF_INIT_HIGH (1 << 1)
0025
0026 #define GPIOF_IN        (GPIOF_DIR_IN)
0027 #define GPIOF_OUT_INIT_LOW  (GPIOF_DIR_OUT | GPIOF_INIT_LOW)
0028 #define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
0029
0030 /* Gpio pin is active-low */
0031 #define GPIOF_ACTIVE_LOW        (1 << 2)
0032
0033 /* Gpio pin is open drain */
0034 #define GPIOF_OPEN_DRAIN    (1 << 3)
0035
0036 /* Gpio pin is open source */
0037 #define GPIOF_OPEN_SOURCE   (1 << 4)
0038
0039 #define GPIOF_EXPORT        (1 << 5)
0040 #define GPIOF_EXPORT_CHANGEABLE (1 << 6)
0041 #define GPIOF_EXPORT_DIR_FIXED  (GPIOF_EXPORT)
0042 #define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE)
0043
0044 /**
0045  * struct gpio - a structure describing a GPIO with configuration
0046  * @gpio:   the GPIO number
0047  * @flags:  GPIO configuration as specified by GPIOF_*
0048  * @label:  a literal description string of this GPIO
0049  */
0050 struct gpio {
0051     unsigned    gpio;
0052     unsigned long   flags;
0053     const char  *label;
0054 };
0055
0056 #ifdef CONFIG_GPIOLIB
0057
0058 #ifdef CONFIG_ARCH_HAVE_CUSTOM_GPIO_H
0059 #include <asm/gpio.h>
0060 #else
0061
0062 #include <asm-generic/gpio.h>
0063
0064 static inline int gpio_get_value(unsigned int gpio)
0065 {
0066     return __gpio_get_value(gpio);
0067 }
0068
0069 static inline void gpio_set_value(unsigned int gpio, int value)
0070 {
0071     __gpio_set_value(gpio, value);
0072 }
0073
0074 static inline int gpio_cansleep(unsigned int gpio)
0075 {
0076     return __gpio_cansleep(gpio);
0077 }
0078
0079 static inline int gpio_to_irq(unsigned int gpio)
0080 {
0081     return __gpio_to_irq(gpio);
0082 }
0083
0084 static inline int irq_to_gpio(unsigned int irq)
0085 {
0086     return -EINVAL;
0087 }
0088
0089 #endif /* ! CONFIG_ARCH_HAVE_CUSTOM_GPIO_H */
0090
0091 /* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */
0092
0093 struct device;
0094
0095 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label);
0096 int devm_gpio_request_one(struct device *dev, unsigned gpio,
0097               unsigned long flags, const char *label);
0098
0099 #else /* ! CONFIG_GPIOLIB */
0100
0101 #include <linux/kernel.h>
0102 #include <linux/types.h>
0103 #include <linux/bug.h>
0104
0105 struct device;
0106 struct gpio_chip;
0107
0108 static inline bool gpio_is_valid(int number)
0109 {
0110     return false;
0111 }
0112
0113 static inline int gpio_request(unsigned gpio, const char *label)
0114 {
0115     return -ENOSYS;
0116 }
0117
0118 static inline int gpio_request_one(unsigned gpio,
0119                     unsigned long flags, const char *label)
0120 {
0121     return -ENOSYS;
0122 }
0123
0124 static inline int gpio_request_array(const struct gpio *array, size_t num)
0125 {
0126     return -ENOSYS;
0127 }
0128
0129 static inline void gpio_free(unsigned gpio)
0130 {
0131     might_sleep();
0132
0133     /* GPIO can never have been requested */
0134     WARN_ON(1);
0135 }
0136
0137 static inline void gpio_free_array(const struct gpio *array, size_t num)
0138 {
0139     might_sleep();
0140
0141     /* GPIO can never have been requested */
0142     WARN_ON(1);
0143 }
0144
0145 static inline int gpio_direction_input(unsigned gpio)
0146 {
0147     return -ENOSYS;
0148 }
0149
0150 static inline int gpio_direction_output(unsigned gpio, int value)
0151 {
0152     return -ENOSYS;
0153 }
0154
0155 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
0156 {
0157     return -ENOSYS;
0158 }
0159
0160 static inline int gpio_get_value(unsigned gpio)
0161 {
0162     /* GPIO can never have been requested or set as {in,out}put */
0163     WARN_ON(1);
0164     return 0;
0165 }
0166
0167 static inline void gpio_set_value(unsigned gpio, int value)
0168 {
0169     /* GPIO can never have been requested or set as output */
0170     WARN_ON(1);
0171 }
0172
0173 static inline int gpio_cansleep(unsigned gpio)
0174 {
0175     /* GPIO can never have been requested or set as {in,out}put */
0176     WARN_ON(1);
0177     return 0;
0178 }
0179
0180 static inline int gpio_get_value_cansleep(unsigned gpio)
0181 {
0182     /* GPIO can never have been requested or set as {in,out}put */
0183     WARN_ON(1);
0184     return 0;
0185 }
0186
0187 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
0188 {
0189     /* GPIO can never have been requested or set as output */
0190     WARN_ON(1);
0191 }
0192
0193 static inline int gpio_export(unsigned gpio, bool direction_may_change)
0194 {
0195     /* GPIO can never have been requested or set as {in,out}put */
0196     WARN_ON(1);
0197     return -EINVAL;
0198 }
0199
0200 static inline int gpio_export_link(struct device *dev, const char *name,
0201                 unsigned gpio)
0202 {
0203     /* GPIO can never have been exported */
0204     WARN_ON(1);
0205     return -EINVAL;
0206 }
0207
0208 static inline void gpio_unexport(unsigned gpio)
0209 {
0210     /* GPIO can never have been exported */
0211     WARN_ON(1);
0212 }
0213
0214 static inline int gpio_to_irq(unsigned gpio)
0215 {
0216     /* GPIO can never have been requested or set as input */
0217     WARN_ON(1);
0218     return -EINVAL;
0219 }
0220
0221 static inline int irq_to_gpio(unsigned irq)
0222 {
0223     /* irq can never have been returned from gpio_to_irq() */
0224     WARN_ON(1);
0225     return -EINVAL;
0226 }
0227
0228 static inline int devm_gpio_request(struct device *dev, unsigned gpio,
0229                     const char *label)
0230 {
0231     WARN_ON(1);
0232     return -EINVAL;
0233 }
0234
0235 static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
0236                     unsigned long flags, const char *label)
0237 {
0238     WARN_ON(1);
0239     return -EINVAL;
0240 }
0241
0242 #endif /* ! CONFIG_GPIOLIB */
0243
0244 #endif /* __LINUX_GPIO_H */