1 /*
2  * Copyright (c) 2019 Piotr Mienkowski
3  * Copyright (c) 2018 Linaro Limited
4  *
5  * SPDX-License-Identifier: Apache-2.0
6  */
7 #ifndef ZEPHYR_INCLUDE_DT_BINDINGS_GPIO_GPIO_H_
8 #define ZEPHYR_INCLUDE_DT_BINDINGS_GPIO_GPIO_H_
9 
10 /**
11  * @brief GPIO Driver APIs
12  * @defgroup gpio_interface GPIO Driver APIs
13  * @ingroup io_interfaces
14  * @{
15  */
16 
17 /** Mask for DT GPIO flags. */
18 #define GPIO_DT_FLAGS_MASK 0x3F
19 
20 /**
21  * @name GPIO pin active level flags
22  * @{
23  */
24 
25 /** GPIO pin is active (has logical value '1') in low state. */
26 #define GPIO_ACTIVE_LOW         (1 << 0)
27 /** GPIO pin is active (has logical value '1') in high state. */
28 #define GPIO_ACTIVE_HIGH        (0 << 0)
29 
30 /** @} */
31 
32 /**
33  * @name GPIO pin drive flags
34  * @{
35  */
36 
37 /** @cond INTERNAL_HIDDEN */
38 
39 /* Configures GPIO output in single-ended mode (open drain or open source). */
40 #define GPIO_SINGLE_ENDED       (1 << 1)
41 /* Configures GPIO output in push-pull mode */
42 #define GPIO_PUSH_PULL          (0 << 1)
43 
44 /* Indicates single ended open drain mode (wired AND). */
45 #define GPIO_LINE_OPEN_DRAIN    (1 << 2)
46 /* Indicates single ended open source mode (wired OR). */
47 #define GPIO_LINE_OPEN_SOURCE   (0 << 2)
48 
49 /** @endcond */
50 
51 /** Configures GPIO output in open drain mode (wired AND).
52  *
53  * @note 'Open Drain' mode also known as 'Open Collector' is an output
54  * configuration which behaves like a switch that is either connected to ground
55  * or disconnected.
56  */
57 #define GPIO_OPEN_DRAIN         (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_DRAIN)
58 /** Configures GPIO output in open source mode (wired OR).
59  *
60  * @note 'Open Source' is a term used by software engineers to describe output
61  * mode opposite to 'Open Drain'. It behaves like a switch that is either
62  * connected to power supply or disconnected. There exist no corresponding
63  * hardware schematic and the term is generally unknown to hardware engineers.
64  */
65 #define GPIO_OPEN_SOURCE        (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_SOURCE)
66 
67 /** @} */
68 
69 /**
70  * @name GPIO pin bias flags
71  * @{
72  */
73 
74 /** Enables GPIO pin pull-up. */
75 #define GPIO_PULL_UP            (1 << 4)
76 
77 /** Enable GPIO pin pull-down. */
78 #define GPIO_PULL_DOWN          (1 << 5)
79 
80 /** @} */
81 
82 /**
83  * Configures GPIO interrupt to wakeup the system from low power mode.
84  */
85 #define GPIO_INT_WAKEUP         (1 << 6)
86 
87 /* Note: Bits 15 downto 8 are reserved for SoC specific flags. */
88 
89 /**
90  * @}
91  */
92 
93 #endif /* ZEPHYR_INCLUDE_DT_BINDINGS_GPIO_GPIO_H_ */
94