zephyr/drivers/spi/spi_nrfx_spi.c

317 lines
7.8 KiB
C

/*
* Copyright (c) 2017 - 2018, Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <spi.h>
#include <nrfx_spi.h>
#define SYS_LOG_DOMAIN "spi_nrfx_spi"
#define SYS_LOG_LEVEL CONFIG_SYS_LOG_SPI_LEVEL
#include <logging/sys_log.h>
#include "spi_context.h"
struct spi_nrfx_data {
struct spi_context ctx;
size_t chunk_len;
bool busy;
};
struct spi_nrfx_config {
nrfx_spi_t spi;
};
static inline struct spi_nrfx_data *get_dev_data(struct device *dev)
{
return dev->driver_data;
}
static inline const struct spi_nrfx_config *get_dev_config(struct device *dev)
{
return dev->config->config_info;
}
static inline nrf_spi_frequency_t get_nrf_spi_frequency(u32_t frequency)
{
/* Get the highest supported frequency not exceeding the requested one.
*/
if (frequency < 250000) {
return NRF_SPI_FREQ_125K;
} else if (frequency < 500000) {
return NRF_SPI_FREQ_250K;
} else if (frequency < 1000000) {
return NRF_SPI_FREQ_500K;
} else if (frequency < 2000000) {
return NRF_SPI_FREQ_1M;
} else if (frequency < 4000000) {
return NRF_SPI_FREQ_2M;
} else if (frequency < 8000000) {
return NRF_SPI_FREQ_4M;
} else {
return NRF_SPI_FREQ_8M;
}
}
static inline nrf_spi_mode_t get_nrf_spi_mode(u16_t operation)
{
if (SPI_MODE_GET(operation) & SPI_MODE_CPOL) {
if (SPI_MODE_GET(operation) & SPI_MODE_CPHA) {
return NRF_SPI_MODE_3;
} else {
return NRF_SPI_MODE_2;
}
} else {
if (SPI_MODE_GET(operation) & SPI_MODE_CPHA) {
return NRF_SPI_MODE_1;
} else {
return NRF_SPI_MODE_0;
}
}
}
static inline nrf_spi_bit_order_t get_nrf_spi_bit_order(u16_t operation)
{
if (operation & SPI_TRANSFER_LSB) {
return NRF_SPI_BIT_ORDER_LSB_FIRST;
} else {
return NRF_SPI_BIT_ORDER_MSB_FIRST;
}
}
static int configure(struct device *dev,
const struct spi_config *spi_cfg)
{
struct spi_context *ctx = &get_dev_data(dev)->ctx;
const nrfx_spi_t *spi = &get_dev_config(dev)->spi;
if (spi_context_configured(ctx, spi_cfg)) {
/* Already configured. No need to do it again. */
return 0;
}
if (SPI_OP_MODE_GET(spi_cfg->operation) != SPI_OP_MODE_MASTER) {
SYS_LOG_ERR("Slave mode is not supported on %s",
dev->config->name);
return -EINVAL;
}
if (spi_cfg->operation & SPI_MODE_LOOP) {
SYS_LOG_ERR("Loopback mode is not supported");
return -EINVAL;
}
if ((spi_cfg->operation & SPI_LINES_MASK) != SPI_LINES_SINGLE) {
SYS_LOG_ERR("Only single line mode is supported");
return -EINVAL;
}
if (SPI_WORD_SIZE_GET(spi_cfg->operation) != 8) {
SYS_LOG_ERR("Word sizes other than 8 bits"
" are not supported");
return -EINVAL;
}
if (spi_cfg->frequency < 125000) {
SYS_LOG_ERR("Frequencies lower than 125 kHz are not supported");
return -EINVAL;
}
ctx->config = spi_cfg;
spi_context_cs_configure(ctx);
nrf_spi_configure(spi->p_reg,
get_nrf_spi_mode(spi_cfg->operation),
get_nrf_spi_bit_order(spi_cfg->operation));
nrf_spi_frequency_set(spi->p_reg,
get_nrf_spi_frequency(spi_cfg->frequency));
return 0;
}
static void transfer_next_chunk(struct device *dev)
{
struct spi_nrfx_data *dev_data = get_dev_data(dev);
struct spi_context *ctx = &dev_data->ctx;
int error = 0;
size_t chunk_len = spi_context_longest_current_buf(ctx);
if (chunk_len > 0) {
nrfx_spi_xfer_desc_t xfer;
nrfx_err_t result;
dev_data->chunk_len = chunk_len;
xfer.p_tx_buffer = ctx->tx_buf;
xfer.tx_length = spi_context_tx_buf_on(ctx) ? chunk_len : 0;
xfer.p_rx_buffer = ctx->rx_buf;
xfer.rx_length = spi_context_rx_buf_on(ctx) ? chunk_len : 0;
result = nrfx_spi_xfer(&get_dev_config(dev)->spi, &xfer, 0);
if (result == NRFX_SUCCESS) {
return;
}
error = -EIO;
}
spi_context_cs_control(ctx, false);
SYS_LOG_DBG("Transaction finished with status %d", error);
spi_context_complete(ctx, error);
dev_data->busy = false;
}
static int transceive(struct device *dev,
const struct spi_config *spi_cfg,
const struct spi_buf_set *tx_bufs,
const struct spi_buf_set *rx_bufs)
{
struct spi_nrfx_data *dev_data = get_dev_data(dev);
int error;
error = configure(dev, spi_cfg);
if (error == 0) {
dev_data->busy = true;
spi_context_buffers_setup(&dev_data->ctx, tx_bufs, rx_bufs, 1);
spi_context_cs_control(&dev_data->ctx, true);
transfer_next_chunk(dev);
error = spi_context_wait_for_completion(&dev_data->ctx);
}
spi_context_release(&dev_data->ctx, error);
return error;
}
static int spi_nrfx_transceive(struct device *dev,
const struct spi_config *spi_cfg,
const struct spi_buf_set *tx_bufs,
const struct spi_buf_set *rx_bufs)
{
spi_context_lock(&get_dev_data(dev)->ctx, false, NULL);
return transceive(dev, spi_cfg, tx_bufs, rx_bufs);
}
#ifdef CONFIG_SPI_ASYNC
static int spi_nrfx_transceive_async(struct device *dev,
const struct spi_config *spi_cfg,
const struct spi_buf_set *tx_bufs,
const struct spi_buf_set *rx_bufs,
struct k_poll_signal *async)
{
spi_context_lock(&get_dev_data(dev)->ctx, true, async);
return transceive(dev, spi_cfg, tx_bufs, rx_bufs);
}
#endif /* CONFIG_SPI_ASYNC */
static int spi_nrfx_release(struct device *dev,
const struct spi_config *spi_cfg)
{
struct spi_nrfx_data *dev_data = get_dev_data(dev);
if (!spi_context_configured(&dev_data->ctx, spi_cfg)) {
return -EINVAL;
}
if (dev_data->busy) {
return -EBUSY;
}
spi_context_unlock_unconditionally(&dev_data->ctx);
return 0;
}
static const struct spi_driver_api spi_nrfx_driver_api = {
.transceive = spi_nrfx_transceive,
#ifdef CONFIG_SPI_ASYNC
.transceive_async = spi_nrfx_transceive_async,
#endif
.release = spi_nrfx_release,
};
static void event_handler(const nrfx_spi_evt_t *p_event, void *p_context)
{
struct device *dev = p_context;
struct spi_nrfx_data *dev_data = get_dev_data(dev);
if (p_event->type == NRFX_SPI_EVENT_DONE) {
spi_context_update_tx(&dev_data->ctx, 1, dev_data->chunk_len);
spi_context_update_rx(&dev_data->ctx, 1, dev_data->chunk_len);
transfer_next_chunk(dev);
}
}
static int init_spi(struct device *dev, const nrfx_spi_config_t *config)
{
/* This sets only default values of frequency, mode and bit order.
* The proper ones are set in configure() when a transfer is started.
*/
nrfx_err_t result = nrfx_spi_init(&get_dev_config(dev)->spi,
config,
event_handler,
dev);
if (result != NRFX_SUCCESS) {
SYS_LOG_ERR("Failed to initialize device: %s",
dev->config->name);
return -EBUSY;
}
spi_context_unlock_unconditionally(&get_dev_data(dev)->ctx);
return 0;
}
#define SPI_NRFX_SPI_DEVICE(idx) \
static int spi_##idx##_init(struct device *dev) \
{ \
IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_SPI##idx), \
CONFIG_SPI_##idx##_IRQ_PRI, \
nrfx_isr, nrfx_spi_##idx##_irq_handler, 0); \
const nrfx_spi_config_t config = { \
.sck_pin = CONFIG_SPI_##idx##_NRF_SCK_PIN, \
.mosi_pin = CONFIG_SPI_##idx##_NRF_MOSI_PIN, \
.miso_pin = CONFIG_SPI_##idx##_NRF_MISO_PIN, \
.ss_pin = NRFX_SPI_PIN_NOT_USED, \
.orc = CONFIG_SPI_##idx##_NRF_ORC, \
.frequency = NRF_SPI_FREQ_4M, \
.mode = NRF_SPI_MODE_0, \
.bit_order = NRF_SPI_BIT_ORDER_MSB_FIRST, \
}; \
return init_spi(dev, &config); \
} \
static struct spi_nrfx_data spi_##idx##_data = { \
SPI_CONTEXT_INIT_LOCK(spi_##idx##_data, ctx), \
SPI_CONTEXT_INIT_SYNC(spi_##idx##_data, ctx), \
.busy = false, \
}; \
static const struct spi_nrfx_config spi_##idx##_config = { \
.spi = NRFX_SPI_INSTANCE(idx), \
}; \
DEVICE_AND_API_INIT(spi_##idx, CONFIG_SPI_##idx##_NAME, \
spi_##idx##_init, \
&spi_##idx##_data, \
&spi_##idx##_config, \
POST_KERNEL, CONFIG_SPI_INIT_PRIORITY, \
&spi_nrfx_driver_api)
#ifdef CONFIG_SPI_0_NRF_SPI
SPI_NRFX_SPI_DEVICE(0);
#endif
#ifdef CONFIG_SPI_1_NRF_SPI
SPI_NRFX_SPI_DEVICE(1);
#endif
#ifdef CONFIG_SPI_2_NRF_SPI
SPI_NRFX_SPI_DEVICE(2);
#endif