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  • /*
     * This is the interface to the sandbox GPIO driver for test code which
     * wants to change the GPIO values reported to U-Boot.
     *
     * Copyright (c) 2011 The Chromium OS Authors.
     * See file CREDITS for list of people who contributed to this
     * project.
     *
     * 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; either version 2 of
     * the License, or (at your option) any later version.
     *
     * 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., 59 Temple Place, Suite 330, Boston,
     * MA 02111-1307 USA
     */
    
    #ifndef __ASM_SANDBOX_GPIO_H
    #define __ASM_SANDBOX_GPIO_H
    
    /*
     * We use the generic interface, and add a back-channel.
     *
     * The back-channel functions are declared in this file. They should not be used
     * except in test code.
     *
     * Test code can, for example, call sandbox_gpio_set_value() to set the value of
     * a simulated GPIO. From then on, normal code in U-Boot will see this new
     * value when it calls gpio_get_value().
     *
     * NOTE: DO NOT use the functions in this file except in test code!
     */
    #include <asm-generic/gpio.h>
    
    /**
     * Return the simulated value of a GPIO (used only in sandbox test code)
     *
     * @param gp	GPIO number
     * @return -1 on error, 0 if GPIO is low, >0 if high
     */
    int sandbox_gpio_get_value(unsigned gp);
    
    /**
     * Set the simulated value of a GPIO (used only in sandbox test code)
     *
     * @param gp	GPIO number
     * @param value	value to set (0 for low, non-zero for high)
     * @return -1 on error, 0 if ok
     */
    int sandbox_gpio_set_value(unsigned gp, int value);
    
    /**
     * Return the simulated direction of a GPIO (used only in sandbox test code)
     *
     * @param gp	GPIO number
     * @return -1 on error, 0 if GPIO is input, >0 if output
     */
    int sandbox_gpio_get_direction(unsigned gp);
    
    /**
     * Set the simulated direction of a GPIO (used only in sandbox test code)
     *
     * @param gp	GPIO number
     * @param output 0 to set as input, 1 to set as output
     * @return -1 on error, 0 if ok
     */
    int sandbox_gpio_set_direction(unsigned gp, int output);
    
    /* Display information about each GPIO */
    void gpio_info(void);
    
    #define gpio_status()	gpio_info()
    
    #endif