xref: /openbmc/linux/include/linux/gpio.h (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 #ifndef __LINUX_GPIO_H
2 #define __LINUX_GPIO_H
3 
4 /* see Documentation/gpio.txt */
5 
6 #ifdef CONFIG_GENERIC_GPIO
7 #include <asm/gpio.h>
8 
9 #else
10 
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 
15 /*
16  * Some platforms don't support the GPIO programming interface.
17  *
18  * In case some driver uses it anyway (it should normally have
19  * depended on GENERIC_GPIO), these routines help the compiler
20  * optimize out much GPIO-related code ... or trigger a runtime
21  * warning when something is wrongly called.
22  */
23 
24 static inline int gpio_is_valid(int number)
25 {
26 	return 0;
27 }
28 
29 static inline int gpio_request(unsigned gpio, const char *label)
30 {
31 	return -ENOSYS;
32 }
33 
34 static inline void gpio_free(unsigned gpio)
35 {
36 	might_sleep();
37 
38 	/* GPIO can never have been requested */
39 	WARN_ON(1);
40 }
41 
42 static inline int gpio_direction_input(unsigned gpio)
43 {
44 	return -ENOSYS;
45 }
46 
47 static inline int gpio_direction_output(unsigned gpio, int value)
48 {
49 	return -ENOSYS;
50 }
51 
52 static inline int gpio_get_value(unsigned gpio)
53 {
54 	/* GPIO can never have been requested or set as {in,out}put */
55 	WARN_ON(1);
56 	return 0;
57 }
58 
59 static inline void gpio_set_value(unsigned gpio, int value)
60 {
61 	/* GPIO can never have been requested or set as output */
62 	WARN_ON(1);
63 }
64 
65 static inline int gpio_cansleep(unsigned gpio)
66 {
67 	/* GPIO can never have been requested or set as {in,out}put */
68 	WARN_ON(1);
69 	return 0;
70 }
71 
72 static inline int gpio_get_value_cansleep(unsigned gpio)
73 {
74 	/* GPIO can never have been requested or set as {in,out}put */
75 	WARN_ON(1);
76 	return 0;
77 }
78 
79 static inline void gpio_set_value_cansleep(unsigned gpio, int value)
80 {
81 	/* GPIO can never have been requested or set as output */
82 	WARN_ON(1);
83 }
84 
85 static inline int gpio_export(unsigned gpio, bool direction_may_change)
86 {
87 	/* GPIO can never have been requested or set as {in,out}put */
88 	WARN_ON(1);
89 	return -EINVAL;
90 }
91 
92 static inline void gpio_unexport(unsigned gpio)
93 {
94 	/* GPIO can never have been exported */
95 	WARN_ON(1);
96 }
97 
98 static inline int gpio_to_irq(unsigned gpio)
99 {
100 	/* GPIO can never have been requested or set as input */
101 	WARN_ON(1);
102 	return -EINVAL;
103 }
104 
105 static inline int irq_to_gpio(unsigned irq)
106 {
107 	/* irq can never have been returned from gpio_to_irq() */
108 	WARN_ON(1);
109 	return -EINVAL;
110 }
111 
112 #endif
113 
114 #endif /* __LINUX_GPIO_H */
115