MakefileBasedBuild/Atmel/sam3x/sam3x-ek/libraries/libboard_sam3x-ek/source/dma_hardware_interface.c

/* ----------------------------------------------------------------------------
 *         ATMEL Microcontroller Software Support
 * ----------------------------------------------------------------------------
 * Copyright (c) 2011, Atmel Corporation
 *
 * All rights reserved.
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 * modification, are permitted provided that the following conditions are met:
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/** \addtogroup dmad_module
 *
 * \section DmaHw Dma Hardware Interface Usage
 * <ul>
 * <li> The DMA controller can handle the transfer between peripherals and memory 
 * and so receives the triggers from the peripherals. The hardware interface number
 * are getting from DMAIF_Get_ChannelNumber().</li>
 
 * <li> DMAIF_IsValidatedPeripherOnDma() helps to check if the given DMAC has associated 
 * peripheral identifier coded by the given  peripheral.</li>
 * 
 * </ul>
*/
/*@{*/
/*@}*/

 /**
 * \file
 *
 * Implementation of the hardware interface of the dma device module.
 *
 */


 /*----------------------------------------------------------------------------
 *        Headers
 *----------------------------------------------------------------------------*/
#include <board.h>

/*----------------------------------------------------------------------------
 *        Local variables
 *----------------------------------------------------------------------------*/
/** Array of DMA Channel definition for SAM3x chip*/
static const DmaHardwareInterface dmaHwIf[] = {
    /* dmac, peripheral,  T/R, Channel Number*/
       {0,   ID_HSMCI,    0,   0},
       {0,   ID_HSMCI,    1,   0},
       {0,   ID_SPI0,     0,   1},
       {0,   ID_SPI0,     1,   2},
       {0,   ID_SSC,      0,   3},
       {0,   ID_SSC,      1,   4},
       {0,   ID_SPI1,     0,   5},
       {0,   ID_SPI1,     1,   6},
       {0,   ID_TWI0,     0,   7},
       {0,   ID_TWI0,     1,   8},
       {0,   ID_USART0,   0,  11},
       {0,   ID_USART0,   1,  12},
       {0,   ID_USART1,   0,  13},
       {0,   ID_USART1,   1,  14},
       {0,   ID_PWM,      0,  15}
};

/*----------------------------------------------------------------------------
 *        Consts
 *----------------------------------------------------------------------------*/
 /** Number of recognized peripheral identifier code for DMA. */
#define NUMPERIPHERAL   (sizeof(dmaHwIf) / sizeof (DmaHardwareInterface))

/*----------------------------------------------------------------------------
 *        Exported functions
 *----------------------------------------------------------------------------*/

/**
 * \brief Get peripheral identifier coded for hardware handshaking interface
 *
 * \param ucDmac      DMA Controller number.
 * \param ucPeriphID  Peripheral ID.
 * \param ucTransfer  Transfer type 0: Tx, 1 :Rx.
 * \return 0-15 peripheral identifier coded.
 *         0xff : no associated peripheral identifier coded.
 */
uint8_t DMAIF_GetChannelNumber (uint8_t ucDmac,
                                 uint8_t ucPeriphID, 
                                 uint8_t ucTransfer)
{
    uint8_t i;
    for (i = 0; i < NUMPERIPHERAL; i++)
    {
        if ((dmaHwIf[i].ucDmac == ucDmac) && (dmaHwIf[i].ucPeriphID == ucPeriphID) && (dmaHwIf[i].ucTransfer == ucTransfer))
        {
            return dmaHwIf[i].ucIfID;
        }
    }
    return 0xff;
}

/**
 * \brief Check if the given DMAC has associated peripheral identifier coded by 
 * the given  peripheral.
 *
 * \param ucDmac      DMA Controller number.
 * \param ucPeriphID  Peripheral ID (0xff : memory only).
 * \return 1:  Is a validated peripher. 0: no associated peripheral identifier coded.
 */
uint8_t DMAIF_IsValidatedPeripherOnDma( uint8_t ucDmac, uint8_t ucPeriphID)
{
    uint8_t i;
    /* It is always validated when transfer to memory */
    if (ucPeriphID == 0xFF) {
        return 1;
    }
    for (i = 0; i < NUMPERIPHERAL; i++)
    {
        if ((dmaHwIf[i].ucDmac == ucDmac) && (dmaHwIf[i].ucPeriphID == ucPeriphID))
        {
            return 1;
        }
    }
    return 0;
}