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/*
* 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_GPIOLIB_H__
#define __SRC_INCLUDE_GPIOLIB_H__
/* A generic type, use accessor macros to actually access the hardware. */
typedef unsigned gpio_t;
/*
* Read the value presented by the set of GPIOs, when each pin is interpreted
* as a number in 0..2 range depending on the external pullup situation.
*
* Depending on the third parameter, the return value is either a set of two
* bit fields, each representing one GPIO value, or a number where each GPIO is
* included multiplied by 3^gpio_num, resulting in a true tertiary value.
*
* gpio[]: pin positions to read. little-endian (less significant value first).
* num_gpio: number of pins to read.
* tertiary: 1: pins are interpreted as a quad coded tertiary.
* 0: pins are interpreted as a set of two bit fields.
*/
int gpio_get_in_tristate_values(gpio_t gpio[], int num_gpio, int tertiary);
/*
* The following functions are not provided by the common library, but must be
* implemented by the appropriate SOC/board instead.
*/
int gpio_get_in_value(gpio_t gpio);
void gpio_set_out_value(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);
#endif
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