/*
* Without a FIFO, we can only shift out one frame's worth of SPI
* data, and read the response back.
*
* TODO: support 16-bit data frames.
*/
static int spi_stm32_shift_frames(SPI_TypeDef *spi, struct spi_stm32_data *data)
{
u16_t operation = data->ctx.config->operation;
if (SPI_OP_MODE_GET(operation) == SPI_OP_MODE_MASTER) {
spi_stm32_shift_m(spi, data);
} else {
spi_stm32_shift_s(spi, data);
}
return spi_stm32_get_err(spi);
}
static int configure(struct device *dev,
const struct spi_config *spi_cfg)
{
struct spi_context *ctx = &get_dev_data(dev)->ctx;
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) {
LOG_ERR("Master mode is not supported on %s",
dev->config->name);
return -EINVAL;
}
if (spi_cfg->operation & SPI_MODE_LOOP) {
LOG_ERR("Loopback mode is not supported");
return -EINVAL;
}
if ((spi_cfg->operation & SPI_LINES_MASK) != SPI_LINES_SINGLE) {
LOG_ERR("Only single line mode is supported");
return -EINVAL;
}
if (SPI_WORD_SIZE_GET(spi_cfg->operation) != 8) {
LOG_ERR("Word sizes other than 8 bits"
" are not supported");
return -EINVAL;
}
if (spi_cfg->cs) {
LOG_ERR("CS control via GPIO is not supported");
return -EINVAL;
}
ctx->config = spi_cfg;
nrf_spis_configure(get_dev_config(dev)->spis.p_reg,
get_nrf_spis_mode(spi_cfg->operation),
get_nrf_spis_bit_order(spi_cfg->operation));
return 0;
}