nes-proj/os/dev/spi.c
2018-09-26 21:42:06 +01:00

231 lines
6.9 KiB
C

/*
* Copyright (c) 2016-2017, Yanzi Networks.
* Copyright (c) 2017, University of Bristol - http://www.bristol.ac.uk/
* All rights reserved.
*
* 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 of the copyright holder 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 HOLDER 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 HOLDER 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.
*/
/*---------------------------------------------------------------------------*/
/**
* \addtogroup spi-hal
* @{
*
* \file
* Implementation of the platform-independent aspects of the SPI HAL
*/
/*---------------------------------------------------------------------------*/
#include <dev/spi.h>
#include "contiki.h"
#include <stdint.h>
#include <stdbool.h>
/*---------------------------------------------------------------------------*/
spi_status_t
spi_acquire(const spi_device_t *dev)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
/* lock and open the bus */
return spi_arch_lock_and_open(dev);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_release(const spi_device_t *dev)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
/* close and unlock the bus */
return spi_arch_close_and_unlock(dev);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_select(const spi_device_t *dev)
{
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_NOT_OWNED;
}
gpio_hal_arch_clear_pin(dev->pin_spi_cs);
return SPI_DEV_STATUS_OK;
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_deselect(const spi_device_t *dev)
{
gpio_hal_arch_set_pin(dev->pin_spi_cs);
return SPI_DEV_STATUS_OK;
}
/*---------------------------------------------------------------------------*/
bool
spi_has_bus(const spi_device_t *dev)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return false;
}
return spi_arch_has_lock(dev);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_write_byte(const spi_device_t *dev, uint8_t data)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_LOCKED;
}
return spi_arch_transfer(dev, &data, 1, 0, 0, 0);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_write(const spi_device_t *dev, const uint8_t *data, int size)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_LOCKED;
}
return spi_arch_transfer(dev, data, size, 0, 0, 0);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_read_byte(const spi_device_t *dev, uint8_t *buf)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_LOCKED;
}
return spi_arch_transfer(dev, NULL, 0, buf, 1, 0);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_read(const spi_device_t *dev, uint8_t *buf, int size)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_LOCKED;
}
return spi_arch_transfer(dev, NULL, 0, buf, size, 0);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_read_skip(const spi_device_t *dev, int size)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_LOCKED;
}
return spi_arch_transfer(dev, NULL, 0, NULL, 0, size);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_transfer(const spi_device_t *dev,
const uint8_t *wdata, int wsize,
uint8_t *rbuf, int rsize, int ignore)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_LOCKED;
}
if(wdata == NULL && wsize > 0) {
return SPI_DEV_STATUS_EINVAL;
}
if(rbuf == NULL && rsize > 0) {
return SPI_DEV_STATUS_EINVAL;
}
return spi_arch_transfer(dev, wdata, wsize, rbuf, rsize, ignore);
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_read_register(const spi_device_t *dev, uint8_t reg, uint8_t *data, int size)
{
spi_status_t status;
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
/* write the register first (will read a status) */
status = spi_write_byte(dev, reg);
if(status != SPI_DEV_STATUS_OK) {
return status;
}
/* then read the value (will read the value) */
status = spi_read(dev, data, size);
if(status != SPI_DEV_STATUS_OK) {
return status;
}
return status;
}
/*---------------------------------------------------------------------------*/
spi_status_t
spi_strobe(const spi_device_t *dev, uint8_t strobe, uint8_t *result)
{
if(dev == NULL || dev->spi_controller >= SPI_CONTROLLER_COUNT) {
return SPI_DEV_STATUS_EINVAL;
}
if(!spi_arch_has_lock(dev)) {
return SPI_DEV_STATUS_BUS_LOCKED;
}
return spi_arch_transfer(dev, &strobe, 1, result, 1, 0);
}
/*---------------------------------------------------------------------------*/
/**
* @}
*/