/*
 * Copyright (c) 2014-2016 IBM Corporation.
 * All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of the <organization> nor the
 *    names of its contributors may be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _hal_hpp_
#define _hal_hpp_

#include "oslmic.h"

/*
 * initialize hardware (IO, SPI, TIMER, IRQ).
 */
void hal_init (void);

/*
 * drive radio NSS pin (0=low, 1=high).
 */
void hal_pin_nss (u1_t val);

/*
 * drive radio RX/TX pins (0=rx, 1=tx).
 */
void hal_pin_rxtx (u1_t val);

/*
 * control radio RST pin (0=low, 1=high, 2=floating)
 */
void hal_pin_rst (u1_t val);

/*
 * perform 8-bit SPI transaction with radio.
 *   - write given byte 'outval'
 *   - read byte and return value
 */
u1_t hal_spi (u1_t outval);

/*
 * disable all CPU interrupts.
 *   - might be invoked nested 
 *   - will be followed by matching call to hal_enableIRQs()
 */
void hal_disableIRQs (void);

/*
 * enable CPU interrupts.
 */
void hal_enableIRQs (void);

/*
 * put system and CPU in low-power mode, sleep until interrupt.
 */
void hal_sleep (void);

/*
 * return 32-bit system time in ticks.
 */
u4_t hal_ticks (void);

/*
 * busy-wait until specified timestamp (in ticks) is reached.
 */
void hal_waitUntil (u4_t time);

/*
 * check and rewind timer for target time.
 *   - return 1 if target time is close
 *   - otherwise rewind timer for target time or full period and return 0
 */
u1_t hal_checkTimer (u4_t targettime);

/*
 * perform fatal failure action.
 *   - called by assertions
 *   - action could be HALT or reboot
 */
void hal_failed (void);


void LmicTimer_IRQHandler ();

#endif // _hal_hpp_