void spi_master_transfer(spi_t *obj, void *tx, size_t tx_length, void *rx, size_t rx_length, uint32_t handler, uint32_t event, DMAUsage hint)
{
if (hint != DMA_USAGE_NEVER && obj->spi.dma_state == DMA_USAGE_ALLOCATED) {
// setup dma done, activate
} else if (hint == DMA_USAGE_NEVER) {
obj->spi.dma_state = DMA_USAGE_NEVER;
spi_enable_event_flags(obj, event, true);
spi_buffer_set(obj, tx, tx_length, rx, rx_length);
// Clear the FIFO
DSPI_HAL_SetFlushFifoCmd(obj->spi.address,true,true);
// Enable the FIFO
DSPI_HAL_SetFifoCmd(obj->spi.address, true, true);
// Start writing to the SPI peripheral
spi_master_write_asynch(obj,SPI_ASYNCH_INITIAL_TX);
// use IRQ
spi_master_enable_interrupt(obj, true);
spi_enable_vector_interrupt(obj, handler, true);
} else {
// setup and activate
}
}
void spi_master_transfer(spi_t *obj, const void *tx, size_t tx_length, void *rx, size_t rx_length, uint8_t bit_width, uint32_t handler, uint32_t event, DMAUsage hint)
{
if(spi_active(obj)) {
return;
}
/* check corner case */
if(tx_length == 0) {
tx_length = rx_length;
tx = (void*) 0;
}
/* First, set the buffer */
spi_buffer_set(obj, tx, tx_length, rx, rx_length, bit_width);
/* If using DMA, allocate channels only if they have not already been allocated */
if (hint != DMA_USAGE_NEVER) {
/* User requested to transfer using DMA */
spi_enable_dma(obj, handler, hint);
/* Check if DMA setup was successful */
if (obj->spi.spiDmaMasterRx.dmaUsageState != DMA_USAGE_ALLOCATED && obj->spi.spiDmaMasterRx.dmaUsageState != DMA_USAGE_TEMPORARY_ALLOCATED) {
/* Set up an interrupt transfer as DMA is unavailable */
DSPI_MasterTransferCreateHandle(spi_address[obj->spi.instance], &obj->spi.spi_master_handle, (dspi_master_transfer_callback_t)handler, NULL);
}
} else {
/* User requested to transfer using interrupts */
/* Disable the DMA */
spi_enable_dma(obj, handler, hint);
/* Set up the interrupt transfer */
DSPI_MasterTransferCreateHandle(spi_address[obj->spi.instance], &obj->spi.spi_master_handle, (dspi_master_transfer_callback_t)handler, NULL);
}
/* Start the transfer */
if (spi_master_transfer_asynch(obj) != kStatus_Success) {
obj->spi.status = kDSPI_Idle;
}
}
