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/*
* (C) Copyright 2009
* Frank Bodammer <frank.bodammer@gcd-solutions.de>
* (C) Copyright 2009 Semihalf, Grzegorz Bernacki
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <malloc.h>
#include <spi.h>
#include <mpc5xxx.h>
void spi_init(void)
{
struct mpc5xxx_spi *spi = (struct mpc5xxx_spi *)MPC5XXX_SPI;
/*
* Its important to use the correct order when initializing the
* registers
*/
out_8(&spi->ddr, 0x0F); /* set all SPI pins as output */
out_8(&spi->pdr, 0x00); /* set SS low */
/* SPI is master, SS is general purpose output */
out_8(&spi->cr1, SPI_CR_MSTR | SPI_CR_SPE);
out_8(&spi->cr2, 0x00); /* normal operation */
out_8(&spi->brr, 0x77); /* baud rate: IPB clock / 2048 */
}
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct spi_slave *slave;
slave = spi_alloc_slave_base(bus, cs);
if (!slave)
return NULL;
return slave;
}
void spi_free_slave(struct spi_slave *slave)
{
free(slave);
}
int spi_claim_bus(struct spi_slave *slave)
{
return 0;
}
void spi_release_bus(struct spi_slave *slave)
{
return;
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
void *din, unsigned long flags)
{
struct mpc5xxx_spi *spi = (struct mpc5xxx_spi *)MPC5XXX_SPI;
int i, iter = bitlen >> 3;
const uchar *txp = dout;
uchar *rxp = din;
debug("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
slave->bus, slave->cs, *(uint *) dout, *(uint *) din, bitlen);
if (flags & SPI_XFER_BEGIN)
setbits_8(&spi->pdr, SPI_PDR_SS);
for (i = 0; i < iter; i++) {
udelay(1000);
debug("spi_xfer: sending %x\n", txp[i]);
out_8(&spi->dr, txp[i]);
while (!(in_8(&spi->sr) & SPI_SR_SPIF)) {
udelay(1000);
if (in_8(&spi->sr) & SPI_SR_WCOL) {
rxp[i] = in_8(&spi->dr);
puts("spi_xfer: write collision\n");
return -1;
}
}
rxp[i] = in_8(&spi->dr);
debug("spi_xfer: received %x\n", rxp[i]);
}
if (flags & SPI_XFER_END)
clrbits_8(&spi->pdr, SPI_PDR_SS);
return 0;
}
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