coreboot-kgpe-d16/src/include/gpio.h
David Hendricks 21db62eb0e gpio: add a function to read GPIO array as base-2 value
This adds gpio_base2_value() which reads an array of 2-state
GPIOs and returns a base-2 value, where gpio[0] represents the
least significant bit.

BUG=none
BRANCH=none
TEST=tested with follow-up patches for pinky

Change-Id: I0d6bfac369da0d68079a38de0988c7b59d269a97
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 27873b7a9ea237d13f0cbafd10033a8d0f821cbe
Original-Change-Id: Ia7ffc16eb60e93413c0812573b9cf0999b92828e
Original-Signed-off-by: David Hendricks <dhendrix@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/228323
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: http://review.coreboot.org/9412
Tested-by: build bot (Jenkins)
Reviewed-by: David Hendricks <dhendrix@chromium.org>
2015-04-10 11:59:30 +02:00

57 lines
2 KiB
C

/*
* This file is part of the coreboot project.
*
* Copyright 2014 Google Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __SRC_INCLUDE_GPIO_H__
#define __SRC_INCLUDE_GPIO_H__
#include <soc/gpio.h>
#include <types.h>
/* <soc/gpio.h> must typedef a gpio_t that fits in 32 bits. */
_Static_assert(sizeof(gpio_t) <= sizeof(u32), "gpio_t doesn't fit in lb_gpio");
/* The following functions must be implemented by SoC/board code. */
int gpio_get(gpio_t gpio);
void gpio_set(gpio_t gpio, int value);
void gpio_input_pulldown(gpio_t gpio);
void gpio_input_pullup(gpio_t gpio);
void gpio_input(gpio_t gpio);
void gpio_output(gpio_t gpio, int value);
/*
* Read the value presented by the set of GPIOs, when each pin is interpreted
* as a base-2 digit (LOW = 0, HIGH = 1).
*
* gpio[]: pin positions to read. gpio[0] is less significant than gpio[1].
* num_gpio: number of pins to read.
*/
int gpio_base2_value(gpio_t gpio[], int num_gpio);
/*
* Read the value presented by the set of GPIOs, when each pin is interpreted
* as a base-3 digit (LOW = 0, HIGH = 1, Z/floating = 2).
* Example: X1 = Z, X2 = 1 -> gpio_base3_value({GPIO(X1), GPIO(X2)}) = 5
* BASE3() from <base3.h> can generate numbers to compare the result to.
*
* gpio[]: pin positions to read. gpio[0] is less significant than gpio[1].
* num_gpio: number of pins to read.
*/
int gpio_base3_value(gpio_t gpio[], int num_gpio);
#endif /* __SRC_INCLUDE_GPIO_H__ */