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