1 /*
2 * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 *
6 * GPIO -- General Purpose Input/Output
7 *
8 * Defines a simple and generic interface to access GPIO device.
9 *
10 */
11
12 #include <assert.h>
13 #include <errno.h>
14
15 #include <drivers/gpio.h>
16
17 /*
18 * The gpio implementation
19 */
20 static const gpio_ops_t *ops;
21
gpio_get_direction(int gpio)22 int gpio_get_direction(int gpio)
23 {
24 assert(ops);
25 assert(ops->get_direction != 0);
26 assert(gpio >= 0);
27
28 return ops->get_direction(gpio);
29 }
30
gpio_set_direction(int gpio,int direction)31 void gpio_set_direction(int gpio, int direction)
32 {
33 assert(ops);
34 assert(ops->set_direction != 0);
35 assert((direction == GPIO_DIR_OUT) || (direction == GPIO_DIR_IN));
36 assert(gpio >= 0);
37
38 ops->set_direction(gpio, direction);
39 }
40
gpio_get_value(int gpio)41 int gpio_get_value(int gpio)
42 {
43 assert(ops);
44 assert(ops->get_value != 0);
45 assert(gpio >= 0);
46
47 return ops->get_value(gpio);
48 }
49
gpio_set_value(int gpio,int value)50 void gpio_set_value(int gpio, int value)
51 {
52 assert(ops);
53 assert(ops->set_value != 0);
54 assert((value == GPIO_LEVEL_LOW) || (value == GPIO_LEVEL_HIGH));
55 assert(gpio >= 0);
56
57 ops->set_value(gpio, value);
58 }
59
gpio_set_pull(int gpio,int pull)60 void gpio_set_pull(int gpio, int pull)
61 {
62 assert(ops);
63 assert(ops->set_pull != 0);
64 assert((pull == GPIO_PULL_NONE) || (pull == GPIO_PULL_UP) ||
65 (pull == GPIO_PULL_DOWN));
66 assert(gpio >= 0);
67
68 ops->set_pull(gpio, pull);
69 }
70
gpio_get_pull(int gpio)71 int gpio_get_pull(int gpio)
72 {
73 assert(ops);
74 assert(ops->get_pull != 0);
75 assert(gpio >= 0);
76
77 return ops->get_pull(gpio);
78 }
79
80 /*
81 * Initialize the gpio. The fields in the provided gpio
82 * ops pointer must be valid.
83 */
gpio_init(const gpio_ops_t * ops_ptr)84 void gpio_init(const gpio_ops_t *ops_ptr)
85 {
86 assert(ops_ptr != 0 &&
87 (ops_ptr->get_direction != 0) &&
88 (ops_ptr->set_direction != 0) &&
89 (ops_ptr->get_value != 0) &&
90 (ops_ptr->set_value != 0));
91
92 ops = ops_ptr;
93 }
94