xref: /freebsd/lib/libgpio/libgpio.h (revision fcb560670601b2a4d87bb31d7531c8dcc37ee71b)
1 /*-
2  * Copyright (c) 2013-2014 Rui Paulo <rpaulo@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
17  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
18  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
20  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
23  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef _LIBGPIO_H_
30 #define _LIBGPIO_H_
31 
32 #include <sys/gpio.h>
33 
34 __BEGIN_DECLS
35 
36 #define	GPIO_INVALID_HANDLE -1
37 typedef int gpio_handle_t;
38 typedef uint32_t gpio_pin_t;
39 
40 /*
41  * Structure describing a GPIO pin configuration.
42  */
43 typedef struct {
44 	gpio_pin_t	g_pin;
45 	char 		g_name[GPIOMAXNAME];
46 	uint32_t	g_caps;
47 	uint32_t	g_flags;
48 } gpio_config_t;
49 
50 typedef enum {
51 	GPIO_VALUE_INVALID 	= -1,
52 	GPIO_VALUE_LOW 		= GPIO_PIN_LOW,
53 	GPIO_VALUE_HIGH 	= GPIO_PIN_HIGH
54 } gpio_value_t;
55 
56 /*
57  * Open /dev/gpiocN or a specific device.
58  */
59 gpio_handle_t	gpio_open(unsigned int);
60 gpio_handle_t	gpio_open_device(const char *);
61 void		gpio_close(gpio_handle_t);
62 /*
63  * Get a list of all the GPIO pins.
64  */
65 int		gpio_pin_list(gpio_handle_t, gpio_config_t **);
66 /*
67  * GPIO pin configuration.
68  *
69  * Retrieve the configuration of a specific GPIO pin.  The pin number is
70  * passed through the gpio_config_t structure.
71  */
72 int		gpio_pin_config(gpio_handle_t, gpio_config_t *);
73 /*
74  * Sets the GPIO flags on a specific GPIO pin.  The pin number and the flags
75  * to be set are passed through the gpio_config_t structure.
76  */
77 int		gpio_pin_set_flags(gpio_handle_t, gpio_config_t *);
78 /*
79  * GPIO pin values.
80  */
81 int		gpio_pin_get(gpio_handle_t, gpio_pin_t);
82 int		gpio_pin_set(gpio_handle_t, gpio_pin_t, int);
83 int		gpio_pin_toggle(gpio_handle_t, gpio_pin_t);
84 /*
85  * Helper functions to set pin states.
86  */
87 int		gpio_pin_low(gpio_handle_t, gpio_pin_t);
88 int		gpio_pin_high(gpio_handle_t, gpio_pin_t);
89 /*
90  * Helper functions to configure pins.
91  */
92 int		gpio_pin_input(gpio_handle_t, gpio_pin_t);
93 int		gpio_pin_output(gpio_handle_t, gpio_pin_t);
94 int		gpio_pin_opendrain(gpio_handle_t, gpio_pin_t);
95 int		gpio_pin_pushpull(gpio_handle_t, gpio_pin_t);
96 int		gpio_pin_tristate(gpio_handle_t, gpio_pin_t);
97 int		gpio_pin_pullup(gpio_handle_t, gpio_pin_t);
98 int		gpio_pin_pulldown(gpio_handle_t, gpio_pin_t);
99 int		gpio_pin_invin(gpio_handle_t, gpio_pin_t);
100 int		gpio_pin_invout(gpio_handle_t, gpio_pin_t);
101 int		gpio_pin_pulsate(gpio_handle_t, gpio_pin_t);
102 
103 __END_DECLS
104 
105 #endif /* _LIBGPIO_H_ */
106