/* Shift a SPI frame as slave. */
static void spi_stm32_shift_s(SPI_TypeDef *spi, struct spi_stm32_data *data)
{
u8_t tx_frame;
u8_t rx_frame;
tx_frame = spi_stm32_next_tx(data);
if (LL_SPI_IsActiveFlag_TXE(spi)) {
LL_SPI_TransmitData8(spi, tx_frame);
/* The update is ignored if TX is off. */
spi_context_update_tx(&data->ctx, 1);
}
if (LL_SPI_IsActiveFlag_RXNE(spi)) {
rx_frame = LL_SPI_ReceiveData8(spi);
if (spi_context_rx_on(&data->ctx)) {
*data->ctx.rx_buf = rx_frame;
spi_context_update_rx(&data->ctx, 1);
}
}
}
static void push_data(struct device *dev)
{
const struct spi_dw_config *info = dev->config->config_info;
struct spi_dw_data *spi = dev->driver_data;
u32_t data = 0U;
u32_t f_tx;
DBG_COUNTER_INIT();
if (spi_context_rx_on(&spi->ctx)) {
f_tx = DW_SPI_FIFO_DEPTH - read_txflr(info->regs) -
read_rxflr(info->regs);
if ((int)f_tx < 0) {
f_tx = 0U; /* if rx-fifo is full, hold off tx */
}
} else {
f_tx = DW_SPI_FIFO_DEPTH - read_txflr(info->regs);
}
while (f_tx) {
if (spi_context_tx_buf_on(&spi->ctx)) {
switch (spi->dfs) {
case 1:
data = UNALIGNED_GET((u8_t *)
(spi->ctx.tx_buf));
break;
case 2:
data = UNALIGNED_GET((u16_t *)
(spi->ctx.tx_buf));
break;
#ifndef CONFIG_ARC
case 4:
data = UNALIGNED_GET((u32_t *)
(spi->ctx.tx_buf));
break;
#endif
}
} else if (spi_context_rx_on(&spi->ctx)) {
/* No need to push more than necessary */
if ((int)(spi->ctx.rx_len - spi->fifo_diff) <= 0) {
break;
}
data = 0U;
} else if (spi_context_tx_on(&spi->ctx)) {
data = 0U;
} else {
/* Nothing to push anymore */
break;
}
write_dr(data, info->regs);
spi_context_update_tx(&spi->ctx, spi->dfs, 1);
spi->fifo_diff++;
f_tx--;
DBG_COUNTER_INC();
}
if (!spi_context_tx_on(&spi->ctx)) {
/* prevents any further interrupts demanding TX fifo fill */
write_txftlr(0, info->regs);
}
LOG_DBG("Pushed: %d", DBG_COUNTER_RESULT());
}