Subversion Repositories openrisc_2011-10-31

#include "support.h"

#include "board.h"

#include "spi.h"

#define SPI_XMIT()                              \

        REG32(SPI_BASE + SPI_CTRL) |= SPI_CTRL_GO;         \

        while(REG32(SPI_BASE + SPI_CTRL) & SPI_CTRL_BSY)

void spi_init (int slave, int fq, int bit_nb, int lsb, int tx_pol, int rx_pol)

{

        int ctrl = 0;

        /* Set devider register to obtain desired serial clock frequency */

        REG32(SPI_BASE + SPI_DEVIDER) =  IN_CLK/(fq*2) - 1;

        /* Set control register */

        ctrl = bit_nb << 3;

        ctrl |= lsb ? SPI_CTRL_LSB : 0;

        ctrl |= tx_pol ? SPI_CTRL_TX_NEGEDGE : 0;

        ctrl |= rx_pol ? SPI_CTRL_RX_NEGEDGE : 0;

        REG32(SPI_BASE + SPI_CTRL) = ctrl;

        /* Activate desired slave device */

        REG32(SPI_BASE + SPI_SS) = 1 << slave;

}

unsigned long spi_xmit (unsigned long val)

{

        REG32(SPI_BASE + SPI_TX) = val;

        SPI_XMIT();

        return REG32(SPI_BASE + SPI_RX);

}