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
gpio_is_valid(int number)41 static inline bool gpio_is_valid(int number)
42 {
43 return number >= 0 && number < ARCH_NR_GPIOS;
44 }
45
46 struct device;
47 struct gpio;
48 struct seq_file;
49 struct module;
50 struct device_node;
51 struct gpio_desc;
52
53 /* caller holds gpio_lock *OR* gpio is marked as requested */
gpio_to_chip(unsigned gpio)54 static 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 */
62 extern int gpio_request(unsigned gpio, const char *label);
63 extern void gpio_free(unsigned gpio);
64
gpio_direction_input(unsigned gpio)65 static inline int gpio_direction_input(unsigned gpio)
66 {
67 return gpiod_direction_input(gpio_to_desc(gpio));
68 }
gpio_direction_output(unsigned gpio,int value)69 static inline int gpio_direction_output(unsigned gpio, int value)
70 {
71 return gpiod_direction_output_raw(gpio_to_desc(gpio), value);
72 }
73
gpio_set_debounce(unsigned gpio,unsigned debounce)74 static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
75 {
76 return gpiod_set_debounce(gpio_to_desc(gpio), debounce);
77 }
78
gpio_get_value_cansleep(unsigned gpio)79 static inline int gpio_get_value_cansleep(unsigned gpio)
80 {
81 return gpiod_get_raw_value_cansleep(gpio_to_desc(gpio));
82 }
gpio_set_value_cansleep(unsigned gpio,int value)83 static 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 */
__gpio_get_value(unsigned gpio)93 static inline int __gpio_get_value(unsigned gpio)
94 {
95 return gpiod_get_raw_value(gpio_to_desc(gpio));
96 }
__gpio_set_value(unsigned gpio,int value)97 static inline void __gpio_set_value(unsigned gpio, int value)
98 {
99 return gpiod_set_raw_value(gpio_to_desc(gpio), value);
100 }
101
__gpio_cansleep(unsigned gpio)102 static inline int __gpio_cansleep(unsigned gpio)
103 {
104 return gpiod_cansleep(gpio_to_desc(gpio));
105 }
106
__gpio_to_irq(unsigned gpio)107 static inline int __gpio_to_irq(unsigned gpio)
108 {
109 return gpiod_to_irq(gpio_to_desc(gpio));
110 }
111
112 extern int gpio_request_one(unsigned gpio, unsigned long flags, const char *label);
113 extern int gpio_request_array(const struct gpio *array, size_t num);
114 extern 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 */
gpio_export(unsigned gpio,bool direction_may_change)120 static inline int gpio_export(unsigned gpio, bool direction_may_change)
121 {
122 return gpiod_export(gpio_to_desc(gpio), direction_may_change);
123 }
124
gpio_export_link(struct device * dev,const char * name,unsigned gpio)125 static 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
gpio_sysfs_set_active_low(unsigned gpio,int value)131 static 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
gpio_unexport(unsigned gpio)136 static inline void gpio_unexport(unsigned gpio)
137 {
138 gpiod_unexport(gpio_to_desc(gpio));
139 }
140
141 #else /* !CONFIG_GPIOLIB */
142
gpio_is_valid(int number)143 static 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
gpio_cansleep(unsigned gpio)153 static inline int gpio_cansleep(unsigned gpio)
154 {
155 return 0;
156 }
157
gpio_get_value_cansleep(unsigned gpio)158 static inline int gpio_get_value_cansleep(unsigned gpio)
159 {
160 might_sleep();
161 return __gpio_get_value(gpio);
162 }
163
gpio_set_value_cansleep(unsigned gpio,int value)164 static 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