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 */
gpio_is_valid(int number)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
gpio_direction_input(unsigned gpio)84 static inline int gpio_direction_input(unsigned gpio)
85 {
86 return gpiod_direction_input(gpio_to_desc(gpio));
87 }
gpio_direction_output(unsigned gpio,int value)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
gpio_get_value_cansleep(unsigned gpio)93 static inline int gpio_get_value_cansleep(unsigned gpio)
94 {
95 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
96 }
gpio_set_value_cansleep(unsigned gpio,int value)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
gpio_get_value(unsigned gpio)102 static inline int gpio_get_value(unsigned gpio)
103 {
104 return gpiod_get_raw_value(gpio_to_desc(gpio));
105 }
gpio_set_value(unsigned gpio,int value)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
gpio_to_irq(unsigned gpio)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
gpio_is_valid(int number)133 static inline bool gpio_is_valid(int number)
134 {
135 return false;
136 }
137
gpio_request(unsigned gpio,const char * label)138 static inline int gpio_request(unsigned gpio, const char *label)
139 {
140 return -ENOSYS;
141 }
142
gpio_request_one(unsigned gpio,unsigned long flags,const char * label)143 static inline int gpio_request_one(unsigned gpio,
144 unsigned long flags, const char *label)
145 {
146 return -ENOSYS;
147 }
148
gpio_request_array(const struct gpio * array,size_t num)149 static inline int gpio_request_array(const struct gpio *array, size_t num)
150 {
151 return -ENOSYS;
152 }
153
gpio_free(unsigned gpio)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
gpio_free_array(const struct gpio * array,size_t num)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
gpio_direction_input(unsigned gpio)170 static inline int gpio_direction_input(unsigned gpio)
171 {
172 return -ENOSYS;
173 }
174
gpio_direction_output(unsigned gpio,int value)175 static inline int gpio_direction_output(unsigned gpio, int value)
176 {
177 return -ENOSYS;
178 }
179
gpio_get_value(unsigned gpio)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
gpio_set_value(unsigned gpio,int value)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
gpio_get_value_cansleep(unsigned gpio)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
gpio_set_value_cansleep(unsigned gpio,int value)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
gpio_to_irq(unsigned gpio)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
devm_gpio_request(struct device * dev,unsigned gpio,const char * label)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
devm_gpio_request_one(struct device * dev,unsigned gpio,unsigned long flags,const char * label)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