Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * NOTE: This header *must not* be included.
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
17struct device;
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/**
34 * struct gpio - a structure describing a GPIO with configuration
35 * @gpio: the GPIO number
36 * @flags: GPIO configuration as specified by GPIOF_*
37 * @label: a literal description string of this GPIO
38 */
39struct gpio {
40 unsigned gpio;
41 unsigned long flags;
42 const char *label;
43};
44
45#ifdef CONFIG_GPIOLIB
46
47#include <linux/gpio/consumer.h>
48
49/*
50 * "valid" GPIO numbers are nonnegative and may be passed to
51 * setup routines like gpio_request(). Only some valid numbers
52 * can successfully be requested and used.
53 *
54 * Invalid GPIO numbers are useful for indicating no-such-GPIO in
55 * platform data and other tables.
56 */
57static inline bool gpio_is_valid(int number)
58{
59 /* only non-negative numbers are valid */
60 return number >= 0;
61}
62
63/*
64 * Platforms may implement their GPIO interface with library code,
65 * at a small performance cost for non-inlined operations and some
66 * extra memory (for code and for per-GPIO table entries).
67 */
68
69/*
70 * At the end we want all GPIOs to be dynamically allocated from 0.
71 * However, some legacy drivers still perform fixed allocation.
72 * Until they are all fixed, leave 0-512 space for them.
73 */
74#define GPIO_DYNAMIC_BASE 512
75/*
76 * Define the maximum of the possible GPIO in the global numberspace.
77 * While the GPIO base and numbers are positive, we limit it with signed
78 * maximum as a lot of code is using negative values for special cases.
79 */
80#define GPIO_DYNAMIC_MAX INT_MAX
81
82/* Always use the library code for GPIO management calls,
83 * or when sleeping may be involved.
84 */
85int gpio_request(unsigned gpio, const char *label);
86void gpio_free(unsigned gpio);
87
88static inline int gpio_direction_input(unsigned gpio)
89{
90 return gpiod_direction_input(gpio_to_desc(gpio));
91}
92static inline int gpio_direction_output(unsigned gpio, int value)
93{
94 return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
95}
96
97static inline int gpio_get_value_cansleep(unsigned gpio)
98{
99 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
100}
101static inline void gpio_set_value_cansleep(unsigned gpio, int value)
102{
103 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
104}
105
106static inline int gpio_get_value(unsigned gpio)
107{
108 return gpiod_get_raw_value(gpio_to_desc(gpio));
109}
110static inline void gpio_set_value(unsigned gpio, int value)
111{
112 return gpiod_set_raw_value(gpio_to_desc(gpio), value);
113}
114
115static inline int gpio_to_irq(unsigned gpio)
116{
117 return gpiod_to_irq(gpio_to_desc(gpio));
118}
119
120int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
121
122int devm_gpio_request(struct device *dev, unsigned gpio, const char *label);
123int 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
133static inline bool gpio_is_valid(int number)
134{
135 return false;
136}
137
138static inline int gpio_request(unsigned gpio, const char *label)
139{
140 return -ENOSYS;
141}
142
143static inline int gpio_request_one(unsigned gpio,
144 unsigned long flags, const char *label)
145{
146 return -ENOSYS;
147}
148
149static inline void gpio_free(unsigned gpio)
150{
151 might_sleep();
152
153 /* GPIO can never have been requested */
154 WARN_ON(1);
155}
156
157static inline int gpio_direction_input(unsigned gpio)
158{
159 return -ENOSYS;
160}
161
162static inline int gpio_direction_output(unsigned gpio, int value)
163{
164 return -ENOSYS;
165}
166
167static inline int gpio_get_value(unsigned gpio)
168{
169 /* GPIO can never have been requested or set as {in,out}put */
170 WARN_ON(1);
171 return 0;
172}
173
174static inline void gpio_set_value(unsigned gpio, int value)
175{
176 /* GPIO can never have been requested or set as output */
177 WARN_ON(1);
178}
179
180static inline int gpio_get_value_cansleep(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
187static inline void gpio_set_value_cansleep(unsigned gpio, int value)
188{
189 /* GPIO can never have been requested or set as output */
190 WARN_ON(1);
191}
192
193static inline int gpio_to_irq(unsigned gpio)
194{
195 /* GPIO can never have been requested or set as input */
196 WARN_ON(1);
197 return -EINVAL;
198}
199
200static inline int devm_gpio_request(struct device *dev, unsigned gpio,
201 const char *label)
202{
203 WARN_ON(1);
204 return -EINVAL;
205}
206
207static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
208 unsigned long flags, const char *label)
209{
210 WARN_ON(1);
211 return -EINVAL;
212}
213
214#endif /* ! CONFIG_GPIOLIB */
215
216#endif /* __LINUX_GPIO_H */