/* ---------------------------------------------------------------------------- | |
* 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. | |
* ---------------------------------------------------------------------------- | |
*/ | |
//------------------------------------------------------------------------------ | |
// Headers | |
//------------------------------------------------------------------------------ | |
#include "spid.h" | |
#include "board.h" | |
//------------------------------------------------------------------------------ | |
// Macros | |
//------------------------------------------------------------------------------ | |
/// Write PMC register | |
#define WRITE_PMC(pPmc, regName, value) pPmc->regName = (value) | |
/// Write SPI register | |
#define WRITE_SPI(pSpi, regName, value) pSpi->regName = (value) | |
/// Read SPI registers | |
#define READ_SPI(pSpi, regName) (pSpi->regName) | |
//------------------------------------------------------------------------------ | |
// Exported functions | |
//------------------------------------------------------------------------------ | |
//------------------------------------------------------------------------------ | |
/// Initializes the Spid structure and the corresponding SPI hardware. | |
/// Always returns 0. | |
/// \param pSpid Pointer to a Spid instance. | |
/// \param pSpiHw Associated SPI peripheral. | |
/// \param spiId SPI peripheral identifier. | |
//------------------------------------------------------------------------------ | |
unsigned char SPID_Configure(Spid *pSpid, AT91S_SPI *pSpiHw, unsigned char spiId) | |
{ | |
// Initialize the SPI structure | |
pSpid->pSpiHw = pSpiHw; | |
pSpid->spiId = spiId; | |
pSpid->semaphore = 1; | |
pSpid->pCurrentCommand = 0; | |
// Enable the SPI clock | |
WRITE_PMC(AT91C_BASE_PMC, PMC_PCER, (1 << pSpid->spiId)); | |
// Execute a software reset of the SPI twice | |
WRITE_SPI(pSpiHw, SPI_CR, AT91C_SPI_SWRST); | |
WRITE_SPI(pSpiHw, SPI_CR, AT91C_SPI_SWRST); | |
// Configure SPI in Master Mode with No CS selected !!! | |
WRITE_SPI(pSpiHw, SPI_MR, AT91C_SPI_MSTR | AT91C_SPI_MODFDIS | AT91C_SPI_PCS); | |
// Disable the PDC transfer | |
WRITE_SPI(pSpiHw, SPI_PTCR, AT91C_PDC_RXTDIS | AT91C_PDC_TXTDIS); | |
// Enable the SPI | |
WRITE_SPI(pSpiHw, SPI_CR, AT91C_SPI_SPIEN); | |
// Enable the SPI clock | |
WRITE_PMC(AT91C_BASE_PMC, PMC_PCDR, (1 << pSpid->spiId)); | |
return 0; | |
} | |
//------------------------------------------------------------------------------ | |
/// Configures the parameters for the device corresponding to the cs. | |
/// \param pSpid Pointer to a Spid instance. | |
/// \param cs number corresponding to the SPI chip select. | |
/// \param csr SPI_CSR value to setup. | |
//------------------------------------------------------------------------------ | |
void SPID_ConfigureCS(Spid *pSpid, unsigned char cs, unsigned int csr) | |
{ | |
AT91S_SPI *pSpiHw = pSpid->pSpiHw; | |
WRITE_SPI(pSpiHw, SPI_CSR[cs], csr); | |
} | |
//------------------------------------------------------------------------------ | |
/// Starts a SPI master transfer. This is a non blocking function. It will | |
/// return as soon as the transfer is started. | |
/// Returns 0 if the transfer has been started successfully; otherwise returns | |
/// SPID_ERROR_LOCK is the driver is in use, or SPID_ERROR if the command is not | |
/// valid. | |
/// \param pSpid Pointer to a Spid instance. | |
/// \param pCommand Pointer to the SPI command to execute. | |
//------------------------------------------------------------------------------ | |
unsigned char SPID_SendCommand(Spid *pSpid, SpidCmd *pCommand) | |
{ | |
AT91S_SPI *pSpiHw = pSpid->pSpiHw; | |
unsigned int spiMr; | |
// Try to get the dataflash semaphore | |
if (pSpid->semaphore == 0) { | |
return SPID_ERROR_LOCK; | |
} | |
pSpid->semaphore--; | |
// Enable the SPI clock | |
WRITE_PMC(AT91C_BASE_PMC, PMC_PCER, (1 << pSpid->spiId)); | |
// Disable transmitter and receiver | |
WRITE_SPI(pSpiHw, SPI_PTCR, AT91C_PDC_RXTDIS | AT91C_PDC_TXTDIS); | |
// Write to the MR register | |
spiMr = READ_SPI(pSpiHw, SPI_MR); | |
spiMr |= AT91C_SPI_PCS; | |
spiMr &= ~((1 << pCommand->spiCs) << 16); | |
WRITE_SPI(pSpiHw, SPI_MR, spiMr); | |
// Initialize the two SPI PDC buffer | |
WRITE_SPI(pSpiHw, SPI_RPR, (int) pCommand->pCmd); | |
WRITE_SPI(pSpiHw, SPI_RCR, pCommand->cmdSize); | |
WRITE_SPI(pSpiHw, SPI_TPR, (int) pCommand->pCmd); | |
WRITE_SPI(pSpiHw, SPI_TCR, pCommand->cmdSize); | |
WRITE_SPI(pSpiHw, SPI_RNPR, (int) pCommand->pData); | |
WRITE_SPI(pSpiHw, SPI_RNCR, pCommand->dataSize); | |
WRITE_SPI(pSpiHw, SPI_TNPR, (int) pCommand->pData); | |
WRITE_SPI(pSpiHw, SPI_TNCR, pCommand->dataSize); | |
// Initialize the callback | |
pSpid->pCurrentCommand = pCommand; | |
// Enable transmitter and receiver | |
WRITE_SPI(pSpiHw, SPI_PTCR, AT91C_PDC_RXTEN | AT91C_PDC_TXTEN); | |
// Enable buffer complete interrupt | |
WRITE_SPI(pSpiHw, SPI_IER, AT91C_SPI_RXBUFF); | |
return 0; | |
} | |
//------------------------------------------------------------------------------ | |
/// The SPI_Handler must be called by the SPI Interrupt Service Routine with the | |
/// corresponding Spi instance. | |
/// The SPI_Handler will unlock the Spi semaphore and invoke the upper application | |
/// callback. | |
/// \param pSpid Pointer to a Spid instance. | |
//------------------------------------------------------------------------------ | |
void SPID_Handler(Spid *pSpid) | |
{ | |
SpidCmd *pSpidCmd = pSpid->pCurrentCommand; | |
AT91S_SPI *pSpiHw = pSpid->pSpiHw; | |
volatile unsigned int spiSr; | |
// Read the status register | |
spiSr = READ_SPI(pSpiHw, SPI_SR); | |
if (spiSr & AT91C_SPI_RXBUFF) { | |
// Disable transmitter and receiver | |
WRITE_SPI(pSpiHw, SPI_PTCR, AT91C_PDC_RXTDIS | AT91C_PDC_TXTDIS); | |
// Disable the SPI clock | |
WRITE_PMC(AT91C_BASE_PMC, PMC_PCDR, (1 << pSpid->spiId)); | |
// Disable buffer complete interrupt | |
WRITE_SPI(pSpiHw, SPI_IDR, AT91C_SPI_RXBUFF); | |
// Release the dataflash semaphore | |
pSpid->semaphore++; | |
// Invoke the callback associated with the current command | |
if (pSpidCmd && pSpidCmd->callback) { | |
pSpidCmd->callback(0, pSpidCmd->pArgument); | |
} | |
// Nothing must be done after. A new DF operation may have been started | |
// in the callback function. | |
} | |
} | |
//------------------------------------------------------------------------------ | |
/// Returns 1 if the SPI driver is currently busy executing a command; otherwise | |
/// returns 0. | |
/// \param pSpid Pointer to a SPI driver instance. | |
//------------------------------------------------------------------------------ | |
unsigned char SPID_IsBusy(const Spid *pSpid) | |
{ | |
if (pSpid->semaphore == 0) { | |
return 1; | |
} | |
else { | |
return 0; | |
} | |
} | |