Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_GENERIC_GPIO_H
3#define _ASM_GENERIC_GPIO_H
4
5#include <linux/types.h>
6#include <linux/errno.h>
7
8#ifdef CONFIG_GPIOLIB
9
10#include <linux/compiler.h>
11#include <linux/gpio/driver.h>
12#include <linux/gpio/consumer.h>
13
14/*
15 * Platforms may implement their GPIO interface with library code,
16 * at a small performance cost for non-inlined operations and some
17 * extra memory (for code and for per-GPIO table entries).
18 */
19
20/*
21 * At the end we want all GPIOs to be dynamically allocated from 0.
22 * However, some legacy drivers still perform fixed allocation.
23 * Until they are all fixed, leave 0-512 space for them.
24 */
25#define GPIO_DYNAMIC_BASE 512
26
27struct device;
28struct gpio;
29struct seq_file;
30struct module;
31struct device_node;
32struct gpio_desc;
33
34/* caller holds gpio_lock *OR* gpio is marked as requested */
35static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
36{
37 return gpiod_to_chip(gpio_to_desc(gpio));
38}
39
40/* Always use the library code for GPIO management calls,
41 * or when sleeping may be involved.
42 */
43extern int gpio_request(unsigned gpio, const char *label);
44extern void gpio_free(unsigned gpio);
45
46static inline int gpio_direction_input(unsigned gpio)
47{
48 return gpiod_direction_input(gpio_to_desc(gpio));
49}
50static inline int gpio_direction_output(unsigned gpio, int value)
51{
52 return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
53}
54
55static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
56{
57 return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
58}
59
60static inline int gpio_get_value_cansleep(unsigned gpio)
61{
62 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
63}
64static inline void gpio_set_value_cansleep(unsigned gpio, int value)
65{
66 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
67}
68
69
70/* A platform's <asm/gpio.h> code may want to inline the I/O calls when
71 * the GPIO is constant and refers to some always-present controller,
72 * giving direct access to chip registers and tight bitbanging loops.
73 */
74static inline int __gpio_get_value(unsigned gpio)
75{
76 return gpiod_get_raw_value(gpio_to_desc(gpio));
77}
78static inline void __gpio_set_value(unsigned gpio, int value)
79{
80 return gpiod_set_raw_value(gpio_to_desc(gpio), value);
81}
82
83static inline int __gpio_cansleep(unsigned gpio)
84{
85 return gpiod_cansleep(gpio_to_desc(gpio));
86}
87
88static inline int __gpio_to_irq(unsigned gpio)
89{
90 return gpiod_to_irq(gpio_to_desc(gpio));
91}
92
93extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
94extern int gpio_request_array(const struct gpio *array, size_t num);
95extern void gpio_free_array(const struct gpio *array, size_t num);
96
97/*
98 * A sysfs interface can be exported by individual drivers if they want,
99 * but more typically is configured entirely from userspace.
100 */
101static inline int gpio_export(unsigned gpio, bool direction_may_change)
102{
103 return gpiod_export(gpio_to_desc(gpio), direction_may_change);
104}
105
106static inline int gpio_export_link(struct device *dev, const char *name,
107 unsigned gpio)
108{
109 return gpiod_export_link(dev, name, gpio_to_desc(gpio));
110}
111
112static inline void gpio_unexport(unsigned gpio)
113{
114 gpiod_unexport(gpio_to_desc(gpio));
115}
116
117#else /* !CONFIG_GPIOLIB */
118
119#include <linux/kernel.h>
120
121/* platforms that don't directly support access to GPIOs through I2C, SPI,
122 * or other blocking infrastructure can use these wrappers.
123 */
124
125static inline int gpio_cansleep(unsigned gpio)
126{
127 return 0;
128}
129
130static inline int gpio_get_value_cansleep(unsigned gpio)
131{
132 might_sleep();
133 return __gpio_get_value(gpio);
134}
135
136static inline void gpio_set_value_cansleep(unsigned gpio, int value)
137{
138 might_sleep();
139 __gpio_set_value(gpio, value);
140}
141
142#endif /* !CONFIG_GPIOLIB */
143
144/*
145 * "valid" GPIO numbers are nonnegative and may be passed to
146 * setup routines like gpio_request(). only some valid numbers
147 * can successfully be requested and used.
148 *
149 * Invalid GPIO numbers are useful for indicating no-such-GPIO in
150 * platform data and other tables.
151 */
152
153static inline bool gpio_is_valid(int number)
154{
155 /* only non-negative numbers are valid */
156 return number >= 0;
157}
158
159#endif /* _ASM_GENERIC_GPIO_H */