xref: /openbmc/linux/tools/gpio/gpio-utils.h (revision 6a143a7c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * GPIO tools - utility helpers library for the GPIO tools
4  *
5  * Copyright (C) 2015 Linus Walleij
6  *
7  * Portions copied from iio_utils and lssio:
8  * Copyright (c) 2010 Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
9  * Copyright (c) 2008 Jonathan Cameron
10  * *
11  */
12 #ifndef _GPIO_UTILS_H_
13 #define _GPIO_UTILS_H_
14 
15 #include <stdbool.h>
16 #include <string.h>
17 #include <linux/types.h>
18 
19 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
20 
21 static inline int check_prefix(const char *str, const char *prefix)
22 {
23 	return strlen(str) > strlen(prefix) &&
24 		strncmp(str, prefix, strlen(prefix)) == 0;
25 }
26 
27 int gpiotools_request_line(const char *device_name,
28 			   unsigned int *lines,
29 			   unsigned int num_lines,
30 			   struct gpio_v2_line_config *config,
31 			   const char *consumer);
32 int gpiotools_set_values(const int fd, struct gpio_v2_line_values *values);
33 int gpiotools_get_values(const int fd, struct gpio_v2_line_values *values);
34 int gpiotools_release_line(const int fd);
35 
36 int gpiotools_get(const char *device_name, unsigned int line);
37 int gpiotools_gets(const char *device_name, unsigned int *lines,
38 		   unsigned int num_lines, unsigned int *values);
39 int gpiotools_set(const char *device_name, unsigned int line,
40 		  unsigned int value);
41 int gpiotools_sets(const char *device_name, unsigned int *lines,
42 		   unsigned int num_lines, unsigned int *values);
43 
44 /* helper functions for gpio_v2_line_values bits */
45 static inline void gpiotools_set_bit(__u64 *b, int n)
46 {
47 	*b |= _BITULL(n);
48 }
49 
50 static inline void gpiotools_change_bit(__u64 *b, int n)
51 {
52 	*b ^= _BITULL(n);
53 }
54 
55 static inline void gpiotools_clear_bit(__u64 *b, int n)
56 {
57 	*b &= ~_BITULL(n);
58 }
59 
60 static inline int gpiotools_test_bit(__u64 b, int n)
61 {
62 	return !!(b & _BITULL(n));
63 }
64 
65 static inline void gpiotools_assign_bit(__u64 *b, int n, bool value)
66 {
67 	if (value)
68 		gpiotools_set_bit(b, n);
69 	else
70 		gpiotools_clear_bit(b, n);
71 }
72 
73 #endif /* _GPIO_UTILS_H_ */
74