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
27 struct device;
28 struct gpio;
29 struct seq_file;
30 struct module;
31 struct device_node;
32 struct gpio_desc;
33
34 /* Always use the library code for GPIO management calls,
35 * or when sleeping may be involved.
36 */
37 extern int gpio_request(unsigned gpio, const char *label);
38 extern void gpio_free(unsigned gpio);
39
gpio_direction_input(unsigned gpio)40 static inline int gpio_direction_input(unsigned gpio)
41 {
42 return gpiod_direction_input(gpio_to_desc(gpio));
43 }
gpio_direction_output(unsigned gpio,int value)44 static inline int gpio_direction_output(unsigned gpio, int value)
45 {
46 return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
47 }
48
gpio_set_debounce(unsigned gpio,unsigned debounce)49 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
50 {
51 return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
52 }
53
gpio_get_value_cansleep(unsigned gpio)54 static inline int gpio_get_value_cansleep(unsigned gpio)
55 {
56 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
57 }
gpio_set_value_cansleep(unsigned gpio,int value)58 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
59 {
60 return gpiod_set_raw_value_cansleep(gpio_to_desc(gpio), value);
61 }
62
63
64 /* A platform's <asm/gpio.h> code may want to inline the I/O calls when
65 * the GPIO is constant and refers to some always-present controller,
66 * giving direct access to chip registers and tight bitbanging loops.
67 */
__gpio_get_value(unsigned gpio)68 static inline int __gpio_get_value(unsigned gpio)
69 {
70 return gpiod_get_raw_value(gpio_to_desc(gpio));
71 }
__gpio_set_value(unsigned gpio,int value)72 static inline void __gpio_set_value(unsigned gpio, int value)
73 {
74 return gpiod_set_raw_value(gpio_to_desc(gpio), value);
75 }
76
__gpio_cansleep(unsigned gpio)77 static inline int __gpio_cansleep(unsigned gpio)
78 {
79 return gpiod_cansleep(gpio_to_desc(gpio));
80 }
81
__gpio_to_irq(unsigned gpio)82 static inline int __gpio_to_irq(unsigned gpio)
83 {
84 return gpiod_to_irq(gpio_to_desc(gpio));
85 }
86
87 extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
88 extern int gpio_request_array(const struct gpio *array, size_t num);
89 extern void gpio_free_array(const struct gpio *array, size_t num);
90
91 /*
92 * A sysfs interface can be exported by individual drivers if they want,
93 * but more typically is configured entirely from userspace.
94 */
gpio_export(unsigned gpio,bool direction_may_change)95 static inline int gpio_export(unsigned gpio, bool direction_may_change)
96 {
97 return gpiod_export(gpio_to_desc(gpio), direction_may_change);
98 }
99
gpio_unexport(unsigned gpio)100 static inline void gpio_unexport(unsigned gpio)
101 {
102 gpiod_unexport(gpio_to_desc(gpio));
103 }
104
105 #else /* !CONFIG_GPIOLIB */
106
107 #include <linux/kernel.h>
108
109 /* platforms that don't directly support access to GPIOs through I2C, SPI,
110 * or other blocking infrastructure can use these wrappers.
111 */
112
gpio_cansleep(unsigned gpio)113 static inline int gpio_cansleep(unsigned gpio)
114 {
115 return 0;
116 }
117
gpio_get_value_cansleep(unsigned gpio)118 static inline int gpio_get_value_cansleep(unsigned gpio)
119 {
120 might_sleep();
121 return __gpio_get_value(gpio);
122 }
123
gpio_set_value_cansleep(unsigned gpio,int value)124 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
125 {
126 might_sleep();
127 __gpio_set_value(gpio, value);
128 }
129
130 #endif /* !CONFIG_GPIOLIB */
131
132 /*
133 * "valid" GPIO numbers are nonnegative and may be passed to
134 * setup routines like gpio_request(). only some valid numbers
135 * can successfully be requested and used.
136 *
137 * Invalid GPIO numbers are useful for indicating no-such-GPIO in
138 * platform data and other tables.
139 */
140
gpio_is_valid(int number)141 static inline bool gpio_is_valid(int number)
142 {
143 /* only non-negative numbers are valid */
144 return number >= 0;
145 }
146
147 #endif /* _ASM_GENERIC_GPIO_H */
148