1#ifndef _ASM_GENERIC_GPIO_H
2#define _ASM_GENERIC_GPIO_H
3
4#include <linux/kernel.h>
5#include <linux/types.h>
6#include <linux/errno.h>
7#include <linux/of.h>
8
9#ifdef CONFIG_GPIOLIB
10
11#include <linux/compiler.h>
12#include <linux/gpio/driver.h>
13#include <linux/gpio/consumer.h>
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 * While the GPIO programming interface defines valid GPIO numbers
20 * to be in the range 0..MAX_INT, this library restricts them to the
21 * smaller range 0..ARCH_NR_GPIOS-1.
22 *
23 * ARCH_NR_GPIOS is somewhat arbitrary; it usually reflects the sum of
24 * builtin/SoC GPIOs plus a number of GPIOs on expanders; the latter is
25 * actually an estimate of a board-specific value.
26 */
27
28#ifndef ARCH_NR_GPIOS
29#define ARCH_NR_GPIOS		512
30#endif
31
32/*
33 * "valid" GPIO numbers are nonnegative and may be passed to
34 * setup routines like gpio_request().  only some valid numbers
35 * can successfully be requested and used.
36 *
37 * Invalid GPIO numbers are useful for indicating no-such-GPIO in
38 * platform data and other tables.
39 */
40
41static inline bool gpio_is_valid(int number)
42{
43	return number >= 0 && number < ARCH_NR_GPIOS;
44}
45
46struct device;
47struct gpio;
48struct seq_file;
49struct module;
50struct device_node;
51struct gpio_desc;
52
53/* caller holds gpio_lock *OR* gpio is marked as requested */
54static inline struct gpio_chip *gpio_to_chip(unsigned gpio)
55{
56	return gpiod_to_chip(gpio_to_desc(gpio));
57}
58
59/* Always use the library code for GPIO management calls,
60 * or when sleeping may be involved.
61 */
62extern int gpio_request(unsigned gpio, const char *label);
63extern void gpio_free(unsigned gpio);
64
65static inline int gpio_direction_input(unsigned gpio)
66{
67	return gpiod_direction_input(gpio_to_desc(gpio));
68}
69static inline int gpio_direction_output(unsigned gpio, int value)
70{
71	return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
72}
73
74static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
75{
76	return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
77}
78
79static inline int gpio_get_value_cansleep(unsigned gpio)
80{
81	return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
82}
83static inline void gpio_set_value_cansleep(unsigned gpio, int value)
84{
85	return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
86}
87
88
89/* A platform's <asm/gpio.h> code may want to inline the I/O calls when
90 * the GPIO is constant and refers to some always-present controller,
91 * giving direct access to chip registers and tight bitbanging loops.
92 */
93static inline int __gpio_get_value(unsigned gpio)
94{
95	return gpiod_get_raw_value(gpio_to_desc(gpio));
96}
97static inline void __gpio_set_value(unsigned gpio, int value)
98{
99	return gpiod_set_raw_value(gpio_to_desc(gpio), value);
100}
101
102static inline int __gpio_cansleep(unsigned gpio)
103{
104	return gpiod_cansleep(gpio_to_desc(gpio));
105}
106
107static inline int __gpio_to_irq(unsigned gpio)
108{
109	return gpiod_to_irq(gpio_to_desc(gpio));
110}
111
112extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
113extern int gpio_request_array(const struct gpio *array, size_t num);
114extern void gpio_free_array(const struct gpio *array, size_t num);
115
116/*
117 * A sysfs interface can be exported by individual drivers if they want,
118 * but more typically is configured entirely from userspace.
119 */
120static inline int gpio_export(unsigned gpio, bool direction_may_change)
121{
122	return gpiod_export(gpio_to_desc(gpio), direction_may_change);
123}
124
125static inline int gpio_export_link(struct device *dev, const char *name,
126				   unsigned gpio)
127{
128	return gpiod_export_link(dev, name, gpio_to_desc(gpio));
129}
130
131static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
132{
133	return gpiod_sysfs_set_active_low(gpio_to_desc(gpio), value);
134}
135
136static inline void gpio_unexport(unsigned gpio)
137{
138	gpiod_unexport(gpio_to_desc(gpio));
139}
140
141#else	/* !CONFIG_GPIOLIB */
142
143static inline bool gpio_is_valid(int number)
144{
145	/* only non-negative numbers are valid */
146	return number >= 0;
147}
148
149/* platforms that don't directly support access to GPIOs through I2C, SPI,
150 * or other blocking infrastructure can use these wrappers.
151 */
152
153static inline int gpio_cansleep(unsigned gpio)
154{
155	return 0;
156}
157
158static inline int gpio_get_value_cansleep(unsigned gpio)
159{
160	might_sleep();
161	return __gpio_get_value(gpio);
162}
163
164static inline void gpio_set_value_cansleep(unsigned gpio, int value)
165{
166	might_sleep();
167	__gpio_set_value(gpio, value);
168}
169
170#endif /* !CONFIG_GPIOLIB */
171
172#endif /* _ASM_GENERIC_GPIO_H */
173