u-boot/include/dt-bindings/gpio/gpio.h
Patrick Delaunay 1bb257a9b3 dt-bindings: gpio: document the new pull-up/pull-down flags
This commit extends the flags that can be used in GPIO specifiers to
indicate if a pull-up resistor or pull-down resistor should be
enabled.

It is the backport of linux commit ede033e1e863c ('dt-bindings:
gpio: document the new pull-up/pull-down flags')
from Thomas Petazzoni <thomas.petazzoni@bootlin.com>
and integrated in v5.1-rc1
https://github.com/torvalds/linux/commit/ede033e1e863c

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2020-04-16 23:06:54 -04:00

42 lines
1.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* This header provides constants for most GPIO bindings.
*
* Most GPIO bindings include a flags cell as part of the GPIO specifier.
* In most cases, the format of the flags cell uses the standard values
* defined in this header.
*/
#ifndef _DT_BINDINGS_GPIO_GPIO_H
#define _DT_BINDINGS_GPIO_GPIO_H
/* Bit 0 express polarity */
#define GPIO_ACTIVE_HIGH 0
#define GPIO_ACTIVE_LOW 1
/* Bit 1 express single-endedness */
#define GPIO_PUSH_PULL 0
#define GPIO_SINGLE_ENDED 2
/* Bit 2 express Open drain or open source */
#define GPIO_LINE_OPEN_SOURCE 0
#define GPIO_LINE_OPEN_DRAIN 4
/*
* Open Drain/Collector is the combination of single-ended open drain interface.
* Open Source/Emitter is the combination of single-ended open source interface.
*/
#define GPIO_OPEN_DRAIN (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_DRAIN)
#define GPIO_OPEN_SOURCE (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_SOURCE)
/* Bit 3 express GPIO suspend/resume and reset persistence */
#define GPIO_PERSISTENT 0
#define GPIO_TRANSITORY 8
/* Bit 4 express pull up */
#define GPIO_PULL_UP 16
/* Bit 5 express pull down */
#define GPIO_PULL_DOWN 32
#endif