/****************************************************************************
* arch/arm/src/calypso/calypso_spi.c
* SPI driver for TI Calypso
*
* Copyright (C) 2010 Harald Welte <laforge@gnumonks.org>
* Copyright (C) 2011 Stefan Richter <ichgeh@l--putt.de>
*
* Part of this source code is derivated from Osmocom-BB project and was
* relicensed as BSD with permission from original authors.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS 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.
*
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/spi.h>
#include <debug.h>
#include "up_arch.h"
#include "calypso_spi.h"
#warning "MOST OF SPI API IS INCOMPLETE! (Wrapper around Osmocom driver)"
extern void spi_init(void);
extern int spi_xfer(uint8_t dev_idx, uint8_t bitlen, const void *dout, void *din);
#ifndef CONFIG_SPI_EXCHANGE
#error "Calypso HW only supports exchange. Enable CONFIG_SPI_EXCHANGE!"
#endif
struct calypso_spidev_s
{
struct spi_dev_s spidev; /* External driver interface */
int nbits; /* Number of transfered bits */
#ifndef CONFIG_SPI_OWNBUS
sem_t exclsem; /* Mutual exclusion of devices */
#endif
};
/* STUBS! */
#ifndef CONFIG_SPI_OWNBUS
static int spi_lock(FAR struct spi_dev_s *dev, bool lock);
#endif
static void spi_select(FAR struct spi_dev_s *dev, enum spi_dev_e devid,
bool selected)
{
}
static uint32_t spi_setfrequency(FAR struct spi_dev_s *dev, uint32_t frequency)
{
return frequency;
}
static void spi_setmode(FAR struct spi_dev_s *dev, enum spi_mode_e mode)
{
}
/* Osmocom wrapper */
static void spi_setbits(FAR struct spi_dev_s *dev, int nbits)
{
((FAR struct calypso_spidev_s *)dev)->nbits = nbits;
}
static void spi_exchange(FAR struct spi_dev_s *dev, FAR const void *txbuffer,
FAR void *rxbuffer, size_t nwords)
{
FAR struct calypso_spidev_s *priv = (FAR struct calypso_spidev_s *)dev;
size_t i;
for(i=0; i<nwords; i++)
spi_xfer(0, priv->nbits, txbuffer+i, rxbuffer+i);
}
static uint16_t spi_send(FAR struct spi_dev_s *dev, uint16_t wd)
{
uint16_t buf = wd;
spi_exchange(dev, &buf, &buf, 1);
return buf;
}
static const struct spi_ops_s g_spiops =
{
#ifndef CONFIG_SPI_OWNBUS
.lock = spi_lock,
#endif
.select = spi_select,
.setfrequency = spi_setfrequency,
.setmode = spi_setmode,
.setbits = spi_setbits,
.status = 0,
#ifdef CONFIG_SPI_CMDDATA
.cmddata = ,
#endif
.send = spi_send,
#ifdef CONFIG_SPI_EXCHANGE
.exchange = spi_exchange,
#else
.sndblock = spi_sndblock,
.recvblock = spi_recvblock,
#endif
.registercallback = 0,
};
static struct calypso_spidev_s g_spidev =
{
.spidev = { &g_spiops },
.nbits = 0,
};
void spi_init(void)
{
putreg16(SPI_SET1_EN_CLK | SPI_SET1_WR_IRQ_DIS | SPI_SET1_RDWR_IRQ_DIS,
SPI_REG(REG_SET1));
putreg16(0x0001, SPI_REG(REG_SET2));
}
int spi_xfer(uint8_t dev_idx, uint8_t bitlen, const void *dout, void *din)
{
uint8_t bytes_per_xfer;
uint8_t reg_status, reg_ctrl = 0;
uint32_t tmp;
if (bitlen == 0)
return 0;
if (bitlen > 32)
return -1;
if (dev_idx > 4)
return -1;
bytes_per_xfer = bitlen / 8;
if (bitlen % 8)
bytes_per_xfer ++;
reg_ctrl |= (bitlen - 1) << SPI_CTRL_NB_SHIFT;
reg_ctrl |= (dev_idx & 0x7) << SPI_CTRL_AD_SHIFT;
if (bitlen <= 8) {
tmp = *(uint8_t *)dout;
tmp <<= 24 + (8-bitlen); /* align to MSB */
} else if (bitlen <= 16) {
tmp = *(uint16_t *)dout;
tmp <<= 16 + (16-bitlen); /* align to MSB */
} else {
tmp = *(uint32_t *)dout;
tmp <<= (32-bitlen); /* align to MSB */
}
dbg("spi_xfer(dev_idx=%u, bitlen=%u, data_out=0x%08x): ",
dev_idx, bitlen, tmp);
/* fill transmit registers */
putreg16(tmp >> 16, SPI_REG(REG_TX_MSB));
putreg16(tmp & 0xffff, SPI_REG(REG_TX_LSB));
/* initiate transfer */
if (din)
reg_ctrl |= SPI_CTRL_RDWR;
else
reg_ctrl |= SPI_CTRL_WR;
putreg16(reg_ctrl, SPI_REG(REG_CTRL));
dbg("reg_ctrl=0x%04x ", reg_ctrl);
/* wait until the transfer is complete */
while (1) {
reg_status = getreg16(SPI_REG(REG_STATUS));
dbg("status=0x%04x ", reg_status);
if (din && (reg_status & SPI_STATUS_RE))
break;
else if (reg_status & SPI_STATUS_WE)
break;
}
/* FIXME: calibrate how much delay we really need (seven 13MHz cycles) */
usleep(1000);
if (din) {
tmp = getreg16(SPI_REG(REG_RX_MSB)) << 16;
tmp |= getreg16(SPI_REG(REG_RX_LSB));
dbg("data_in=0x%08x ", tmp);
if (bitlen <= 8)
*(uint8_t *)din = tmp & 0xff;
else if (bitlen <= 16)
*(uint16_t *)din = tmp & 0xffff;
else
*(uint32_t *)din = tmp;
}
dbg("\n");
return 0;
}
FAR struct spi_dev_s *up_spiinitialize(int port)
{
switch(port) {
case 0: /* SPI master device */
spi_init();
return (FAR struct spi_dev_s *)&g_spidev;
case 1: /* uWire device */
return NULL;
default:
return NULL;
}
}