AP_InertialSensor: ensure fifo reads use transfer() to optimize buffer allocation and copying

This commit is contained in:
Andy Piper 2024-09-19 15:26:53 +01:00 committed by Andrew Tridgell
parent 7d426f4741
commit d76132ec63

View File

@ -555,9 +555,30 @@ void AP_InertialSensor_Invensensev3::read_fifo()
while (n_samples > 0) {
uint8_t n = MIN(n_samples, INV3_FIFO_BUFFER_LEN);
if (!block_read(reg_data, (uint8_t*)fifo_buffer, n * fifo_sample_size)) {
goto check_registers;
if (!dev->set_chip_select(true)) {
if (!block_read(reg_data, (uint8_t*)fifo_buffer, n * fifo_sample_size)) {
goto check_registers;
}
} else {
// we don't use read_registers() here to ensure that the fifo buffer that we have allocated
// gets passed all the way down to the SPI DMA handling. This involves one transfer to send
// the register read and then another using the same buffer and length which is handled specially
// for the read
uint8_t reg = reg_data | BIT_READ_FLAG;
if (!dev->transfer(&reg, 1, nullptr, 0)) {
dev->set_chip_select(false);
goto check_registers;
}
// transfer will also be sending data, make sure that data is zero
memset((uint8_t*)fifo_buffer, 0, n * fifo_sample_size);
if (!dev->transfer((uint8_t*)fifo_buffer, n * fifo_sample_size, (uint8_t*)fifo_buffer, n * fifo_sample_size)) {
dev->set_chip_select(false);
goto check_registers;
}
dev->set_chip_select(false);
}
#if HAL_INS_HIGHRES_SAMPLE
if (highres_sampling) {
if (!accumulate_highres_samples((FIFODataHighRes*)fifo_buffer, n)) {