spi.c
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/*
* Copyright (C) 2015 Kaspar Schleiser <kaspar@schleiser.de>
* 2016 Freie Universität Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser General
* Public License v2.1. See the file LICENSE in the top level directory for more
* details.
*/
/**
* @ingroup drivers
* @{
*
* @file
* @brief common SPI function fallback implementations
*
* @author Kaspar Schleiser <kaspar@schleiser.de>
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*
* @}
*/
#include <stddef.h>
#include "board.h"
#include "cpu.h"
#include "periph/spi.h"
#ifdef SPI_NUMOF
#ifdef PERIPH_SPI_NEEDS_INIT_CS
int spi_init_cs(spi_t bus, spi_cs_t cs)
{
if (bus >= SPI_NUMOF) {
return SPI_NODEV;
}
if ((cs == SPI_CS_UNDEF) || (cs == GPIO_UNDEF)) {
return SPI_NOCS;
}
gpio_init((gpio_t)cs, GPIO_OUT);
gpio_set((gpio_t)cs);
return SPI_OK;
}
#endif
#ifdef PERIPH_SPI_NEEDS_TRANSFER_BYTE
uint8_t spi_transfer_byte(spi_t bus, spi_cs_t cs, bool cont, uint8_t out)
{
uint8_t in;
spi_transfer_bytes(bus, cs, cont, &out, &in, 1);
return in;
}
#endif
#ifdef PERIPH_SPI_NEEDS_TRANSFER_REG
uint8_t spi_transfer_reg(spi_t bus, spi_cs_t cs, uint8_t reg, uint8_t out)
{
spi_transfer_bytes(bus, cs, true, ®, NULL, 1);
return spi_transfer_byte(bus, cs, false, out);
}
#endif
#ifdef PERIPH_SPI_NEEDS_TRANSFER_REGS
void spi_transfer_regs(spi_t bus, spi_cs_t cs,
uint8_t reg, const void *out, void *in, size_t len)
{
spi_transfer_bytes(bus, cs, true, ®, NULL, 1);
spi_transfer_bytes(bus, cs, false, out, in, len);
}
#endif
#endif /* SPI_NUMOF */