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/* power.c */
/* binwatch - Tiny binary wristwatch. {{{
 *
 * Copyright (C) 2011 Nicolas Schodet
 *
 * 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.
 *
 * Contact :
 *        Web: http://ni.fr.eu.org/
 *      Email: <nico at ni.fr.eu.org>
 * }}} */
#include "common.h"
#include "power.h"
#include "io.h"

#include <avr/sleep.h>

void
power_init (void)
{
    /* Change initial clock. */
    power_clock_prescale_set (AC_POWER_CLKPS_INITIAL);
    /* Shutdown unused peripherals. */
    /*  Analog comparator. */
    ACSR = _BV (ACD);
    /*  Timers, USI and ADC. */
    PRR = _BV (PRTIM1) | _BV (PRTIM0) | _BV (PRUSI) | _BV (PRADC);
    /*  B3, B4, B5 input values are never read. */
    DIDR0 = 0b111000;
}

void
power_sleep (void)
{
    /* Enable interrupts right before sleep instruction so that any pending
     * interrupt will occur after the processor go to sleep and really wake
     * the processor.  See avr-libc documentation. */
    set_sleep_mode (SLEEP_MODE_PWR_DOWN);
    sleep_enable ();
    sei ();
    sleep_cpu ();
    sleep_disable ();
    cli ();
}