xref: /openbmc/linux/include/linux/gpio.h (revision fea88a0c)
1 #ifndef __LINUX_GPIO_H
2 #define __LINUX_GPIO_H
3 
4 /* see Documentation/gpio.txt */
5 
6 /* make these flag values available regardless of GPIO kconfig options */
7 #define GPIOF_DIR_OUT	(0 << 0)
8 #define GPIOF_DIR_IN	(1 << 0)
9 
10 #define GPIOF_INIT_LOW	(0 << 1)
11 #define GPIOF_INIT_HIGH	(1 << 1)
12 
13 #define GPIOF_IN		(GPIOF_DIR_IN)
14 #define GPIOF_OUT_INIT_LOW	(GPIOF_DIR_OUT | GPIOF_INIT_LOW)
15 #define GPIOF_OUT_INIT_HIGH	(GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
16 
17 /* Gpio pin is open drain */
18 #define GPIOF_OPEN_DRAIN	(1 << 2)
19 
20 /* Gpio pin is open source */
21 #define GPIOF_OPEN_SOURCE	(1 << 3)
22 
23 /**
24  * struct gpio - a structure describing a GPIO with configuration
25  * @gpio:	the GPIO number
26  * @flags:	GPIO configuration as specified by GPIOF_*
27  * @label:	a literal description string of this GPIO
28  */
29 struct gpio {
30 	unsigned	gpio;
31 	unsigned long	flags;
32 	const char	*label;
33 };
34 
35 #ifdef CONFIG_GENERIC_GPIO
36 #include <asm/gpio.h>
37 
38 #else
39 
40 #include <linux/kernel.h>
41 #include <linux/types.h>
42 #include <linux/errno.h>
43 #include <linux/bug.h>
44 
45 struct device;
46 struct gpio_chip;
47 
48 static inline bool gpio_is_valid(int number)
49 {
50 	return false;
51 }
52 
53 static inline int gpio_request(unsigned gpio, const char *label)
54 {
55 	return -ENOSYS;
56 }
57 
58 static inline int gpio_request_one(unsigned gpio,
59 					unsigned long flags, const char *label)
60 {
61 	return -ENOSYS;
62 }
63 
64 static inline int gpio_request_array(const struct gpio *array, size_t num)
65 {
66 	return -ENOSYS;
67 }
68 
69 static inline void gpio_free(unsigned gpio)
70 {
71 	might_sleep();
72 
73 	/* GPIO can never have been requested */
74 	WARN_ON(1);
75 }
76 
77 static inline void gpio_free_array(const struct gpio *array, size_t num)
78 {
79 	might_sleep();
80 
81 	/* GPIO can never have been requested */
82 	WARN_ON(1);
83 }
84 
85 static inline int gpio_direction_input(unsigned gpio)
86 {
87 	return -ENOSYS;
88 }
89 
90 static inline int gpio_direction_output(unsigned gpio, int value)
91 {
92 	return -ENOSYS;
93 }
94 
95 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
96 {
97 	return -ENOSYS;
98 }
99 
100 static inline int gpio_get_value(unsigned gpio)
101 {
102 	/* GPIO can never have been requested or set as {in,out}put */
103 	WARN_ON(1);
104 	return 0;
105 }
106 
107 static inline void gpio_set_value(unsigned gpio, int value)
108 {
109 	/* GPIO can never have been requested or set as output */
110 	WARN_ON(1);
111 }
112 
113 static inline int gpio_cansleep(unsigned gpio)
114 {
115 	/* GPIO can never have been requested or set as {in,out}put */
116 	WARN_ON(1);
117 	return 0;
118 }
119 
120 static inline int gpio_get_value_cansleep(unsigned gpio)
121 {
122 	/* GPIO can never have been requested or set as {in,out}put */
123 	WARN_ON(1);
124 	return 0;
125 }
126 
127 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
128 {
129 	/* GPIO can never have been requested or set as output */
130 	WARN_ON(1);
131 }
132 
133 static inline int gpio_export(unsigned gpio, bool direction_may_change)
134 {
135 	/* GPIO can never have been requested or set as {in,out}put */
136 	WARN_ON(1);
137 	return -EINVAL;
138 }
139 
140 static inline int gpio_export_link(struct device *dev, const char *name,
141 				unsigned gpio)
142 {
143 	/* GPIO can never have been exported */
144 	WARN_ON(1);
145 	return -EINVAL;
146 }
147 
148 static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
149 {
150 	/* GPIO can never have been requested */
151 	WARN_ON(1);
152 	return -EINVAL;
153 }
154 
155 static inline void gpio_unexport(unsigned gpio)
156 {
157 	/* GPIO can never have been exported */
158 	WARN_ON(1);
159 }
160 
161 static inline int gpio_to_irq(unsigned gpio)
162 {
163 	/* GPIO can never have been requested or set as input */
164 	WARN_ON(1);
165 	return -EINVAL;
166 }
167 
168 static inline int irq_to_gpio(unsigned irq)
169 {
170 	/* irq can never have been returned from gpio_to_irq() */
171 	WARN_ON(1);
172 	return -EINVAL;
173 }
174 
175 #endif
176 
177 #endif /* __LINUX_GPIO_H */
178