xref: /openbmc/linux/include/dt-bindings/gpio/gpio.h (revision 2cf1c348)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * This header provides constants for most GPIO bindings.
4  *
5  * Most GPIO bindings include a flags cell as part of the GPIO specifier.
6  * In most cases, the format of the flags cell uses the standard values
7  * defined in this header.
8  */
9 
10 #ifndef _DT_BINDINGS_GPIO_GPIO_H
11 #define _DT_BINDINGS_GPIO_GPIO_H
12 
13 /* Bit 0 express polarity */
14 #define GPIO_ACTIVE_HIGH 0
15 #define GPIO_ACTIVE_LOW 1
16 
17 /* Bit 1 express single-endedness */
18 #define GPIO_PUSH_PULL 0
19 #define GPIO_SINGLE_ENDED 2
20 
21 /* Bit 2 express Open drain or open source */
22 #define GPIO_LINE_OPEN_SOURCE 0
23 #define GPIO_LINE_OPEN_DRAIN 4
24 
25 /*
26  * Open Drain/Collector is the combination of single-ended open drain interface.
27  * Open Source/Emitter is the combination of single-ended open source interface.
28  */
29 #define GPIO_OPEN_DRAIN (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_DRAIN)
30 #define GPIO_OPEN_SOURCE (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_SOURCE)
31 
32 /* Bit 3 express GPIO suspend/resume and reset persistence */
33 #define GPIO_PERSISTENT 0
34 #define GPIO_TRANSITORY 8
35 
36 /* Bit 4 express pull up */
37 #define GPIO_PULL_UP 16
38 
39 /* Bit 5 express pull down */
40 #define GPIO_PULL_DOWN 32
41 
42 #endif
43