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/* ----------------------------------------------------------------------------
* ATMEL Microcontroller Software Support
* ----------------------------------------------------------------------------
* Copyright (c) 2008, Atmel 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 disclaimer below.
*
* Atmel's name may not be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
* DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
* ----------------------------------------------------------------------------
*/
//------------------------------------------------------------------------------
/// \unit
///
/// !!!Purpose
///
/// The Spi driver is a low level spi driver which performs SPI device Initializes,
/// spi transfer and receive. It can be used by upper SPI driver such as AT45
/// driver and AT26 driver.
///
/// !!!Usage
///
/// -# Initializes a SPI instance and the corresponding SPI hardware,
/// Configure SPI in Master Mode using SPID_Configure().
/// -# Configures the SPI characteristics (such as Clock Polarity, Phase,
/// transfers delay and Baud Rate) for the device corresponding to the
/// chip select using SPID_ConfigureCS().
/// -# Starts a SPI master transfer using SPID_SendCommand().
/// The transfer is performed using the PDC channels.
/// -# It enable the SPI clock.
/// -# Set the corresponding peripheral chip select.
/// -# Initialize the two SPI PDC buffers.
/// - Initialize SPI_TPR and SPI_TCR with SPI command data and size
/// to send command data first.
/// - Initialize SPI_RPR and SPI_RCR with SPI command data and size
/// as dummy value.
/// - Initialize SPI_TNPR and SPI_TNCR with rest of the data to be
/// transfered.(if the data specified in cmd structure)
/// - Initialize SPI_RNPR and SPI_RNCR with rest of the data to be
/// received.(if the data specified in cmd structure)
/// -# Initialize the callback function if specified.
/// -# Enable transmitter and receiver.
/// -# Example for sending a command to the dataflash through the SPI.
/// \code
/// /// Build command to be sent.
/// ...
/// // Send Command and data through the SPI
/// if (SPID_SendCommand(pAt45->pSpid, pCommand)) {
/// return AT45_ERROR_SPI;
/// }
/// \endcode
/// -# The SPI_Handler() must be called by the SPI Interrupt Service Routine
/// with the corresponding Spi instance. It is invokes to check for pending
/// interrupts.
/// - Example for initializing SPI interrupt handler in upper application.
/// \code
/// AIC_ConfigureIT(AT91C_ID_SPI, 0, SPI_Handler);
/// \endcode
//------------------------------------------------------------------------------
#ifndef SPID_H
#define SPID_H
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#include <board.h>
//------------------------------------------------------------------------------
// Definitions
//------------------------------------------------------------------------------
/// An unspecified error has occured.
#define SPID_ERROR 1
/// SPI driver is currently in use.
#define SPID_ERROR_LOCK 2
//------------------------------------------------------------------------------
// Macros
//------------------------------------------------------------------------------
/// Calculates the value of the SCBR field of the Chip Select Register given
/// MCK and SPCK.
#define SPID_CSR_SCBR(mck, spck) ((((mck) / (spck)) << 8) & AT91C_SPI_SCBR)
/// Calculates the value of the DLYBS field of the Chip Select Register given
/// the delay in ns and MCK.
#define SPID_CSR_DLYBS(mck, delay) \
((((((delay) * ((mck) / 1000000)) / 1000) + 1) << 16) & AT91C_SPI_DLYBS)
/// Calculates the value of the DLYBCT field of the Chip Select Register given
/// the delay in ns and MCK.
#define SPID_CSR_DLYBCT(mck, delay) \
((((((delay) / 32 * ((mck) / 1000000)) / 1000) + 1) << 24) & AT91C_SPI_DLYBCT)
//------------------------------------------------------------------------------
// Types
//------------------------------------------------------------------------------
/// SPI transfer complete callback.
typedef void (*SpidCallback )(unsigned char, void *);
//------------------------------------------------------------------------------
/// Spi Transfer Request prepared by the application upper layer. This structure
/// is sent to the SPI_SendCommand function to start the transfer. At the end of
/// the transfer, the callback is invoked by the interrupt handler.
//------------------------------------------------------------------------------
typedef struct _SpidCmd {
/// Pointer to the command data.
unsigned char *pCmd;
/// Command size in bytes.
unsigned char cmdSize;
/// Pointer to the data to be sent.
unsigned char *pData;
/// Data size in bytes.
unsigned short dataSize;
/// SPI chip select.
unsigned char spiCs;
/// Callback function invoked at the end of transfer.
SpidCallback callback;
/// Callback arguments.
void *pArgument;
} SpidCmd;
//------------------------------------------------------------------------------
/// Constant structure associated with SPI port. This structure prevents
/// client applications to have access in the same time.
//------------------------------------------------------------------------------
typedef struct {
/// Pointer to SPI Hardware registers
AT91S_SPI *pSpiHw;
/// SPI Id as defined in the product datasheet
char spiId;
/// Current SpiCommand being processed
SpidCmd *pCurrentCommand;
/// Mutual exclusion semaphore.
volatile char semaphore;
} Spid;
//------------------------------------------------------------------------------
// Exported functions
//------------------------------------------------------------------------------
extern unsigned char SPID_Configure(
Spid *pSpid,
AT91S_SPI *pSpiHw,
unsigned char spiId);
extern void SPID_ConfigureCS(Spid *pSpid, unsigned char cs, unsigned int csr);
extern unsigned char SPID_SendCommand(
Spid *pSpid,
SpidCmd *pCommand);
extern void SPID_Handler(Spid *pSpid);
extern unsigned char SPID_IsBusy(const Spid *pSpid);
#endif // #ifndef SPID_H
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