/*
 *  Copyright (c) 2016, The OpenThread Authors.
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. 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.
 *  3. Neither the name of the copyright holder 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 THE COPYRIGHT HOLDER OR CONTRIBUTORS 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.
 */

/**
 * @file
 * @brief
 *   This file defines flash interface.
 */

#ifndef OT_PLATFORM_FLASH_H
#define OT_PLATFORM_FLASH_H

#include <stdint.h>

#include <openthread-types.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
 * Perform any initialization for flash driver.
 *
 * @retval ::kThreadError_None    Initialize flash driver success.
 * @retval ::kThreadError_Failed  Initialize flash driver fail.
 */
ThreadError otPlatFlashInit(void);

/**
 * Get the size of flash that can be read/write by the caller.
 * The usable flash size is always the multiple of flash page size.
 *
 * @returns The size of the flash.
 */
uint32_t otPlatFlashGetSize(void);

/**
 * Erase one flash page that include the input address.
 * This is a non-blocking function. It can work with otPlatFlashStatusWait to check when erase is done.
 *
 * The flash address starts from 0, and this function maps the input address to the physical address of flash for erasing.
 * 0 is always mapped to the beginning of one flash page.
 * The input address should never be mapped to the firmware space or any other protected flash space.
 *
 * @param[in]  aAddress  The start address of the flash to erase.
 *
 * @retval kThreadError_None           Erase flash operation is started.
 * @retval kThreadError_Failed         Erase flash operation is not started.
 * @retval kThreadError_InvalidArgs    aAddress is out of range of flash or not aligend.
 */
ThreadError otPlatFlashErasePage(uint32_t aAddress);

/**
  * Check whether flash is ready or busy.
  *
  * @param[in]  aTimeout  The interval in milliseconds waiting for the flash operation to be done and become ready again.
  *                       zero indicates that it is a polling function, and returns current status of flash immediately.
  *                       non-zero indicates that it is blocking there until the operation is done and become ready, or timeout expires.
  *
  * @retval kThreadError_None           Flash is ready for any operation.
  * @retval kThreadError_Busy           Flash is busy.
  */
ThreadError otPlatFlashStatusWait(uint32_t aTimeout);

/**
 * Write flash. The write operation only clears bits, but never set bits.
 *
 * The flash address starts from 0, and this function maps the input address to the physical address of flash for writing.
 * 0 is always mapped to the beginning of one flash page.
 * The input address should never be mapped to the firmware space or any other protected flash space.
 *
 * @param[in]  aAddress  The start address of the flash to write.
 * @param[in]  aData     The pointer of the data to write.
 * @param[in]  aSize     The size of the data to write.
 *
 * @returns The actual size of octets write to flash.
 *          It is expected the same as aSize, and may be less than aSize.
 *          0 indicates that something wrong happens when writing.
 */
uint32_t otPlatFlashWrite(uint32_t aAddress, uint8_t *aData, uint32_t aSize);

/**
 * Read flash.
 *
 * The flash address starts from 0, and this function maps the input address to the physical address of flash for reading.
 * 0 is always mapped to the beginning of one flash page.
 * The input address should never be mapped to the firmware space or any other protected flash space.
 *
 * @param[in]   aAddress  The start address of the flash to read.
 * @param[Out]  aData     The pointer of buffer for reading.
 * @param[in]   aSize     The size of the data to read.
 *
 * @returns The actual size of octets read to buffer.
 *          It is expected the same as aSize, and may be less than aSize.
 *          0 indicates that something wrong happens when reading.
 */
uint32_t otPlatFlashRead(uint32_t aAddress, uint8_t *aData, uint32_t aSize);

#ifdef __cplusplus
}  // extern "C"
#endif

#endif  // OT_PLATFORM_FLASH_H