ardupilot/libraries/AP_HAL_Linux/SPIUARTDriver.cpp

158 lines
3.8 KiB
C++

#include "SPIUARTDriver.h"
#include <assert.h>
#include <stdlib.h>
#include <cstdio>
#include <AP_HAL/AP_HAL.h>
#include <AP_Math/AP_Math.h>
extern const AP_HAL::HAL &hal;
#ifdef SPIUART_DEBUG
#include <stdio.h>
#define debug(fmt, args ...) do {hal.console->printf("[SPIUARTDriver]: %s:%d: " fmt "\n", __FUNCTION__, __LINE__, ## args); } while(0)
#define error(fmt, args ...) do {fprintf(stderr,"%s:%d: " fmt "\n", __FUNCTION__, __LINE__, ## args); } while(0)
#else
#define debug(fmt, args ...)
#define error(fmt, args ...)
#endif
using namespace Linux;
SPIUARTDriver::SPIUARTDriver()
: UARTDriver(false)
{
}
void SPIUARTDriver::_begin(uint32_t b, uint16_t rxS, uint16_t txS)
{
if (device_path != nullptr) {
UARTDriver::begin(b, rxS, txS);
if (is_initialized()) {
_external = true;
return;
}
}
if (!is_initialized()) {
_dev = hal.spi->get_device("ublox");
if (!_dev) {
return;
}
}
if (rxS < 1024) {
rxS = 2048;
}
if (txS < 1024) {
txS = 2048;
}
_readbuf.set_size(rxS);
_writebuf.set_size(txS);
if (_buffer == nullptr) {
/* Do not allocate new buffer, if we're just changing speed */
_buffer = NEW_NOTHROW uint8_t[rxS];
if (_buffer == nullptr) {
hal.console->printf("Not enough memory\n");
AP_HAL::panic("Not enough memory");
}
}
switch (b) {
case 4000000U:
if (is_initialized()) {
/* Do not allow speed changes before device is initialized, because
* it can lead to misconfiguraration. Once the device is initialized,
* it's sage to update speed
*/
_dev->set_speed(AP_HAL::Device::SPEED_HIGH);
high_speed_set = true;
debug("Set higher SPI-frequency");
} else {
_dev->set_speed(AP_HAL::Device::SPEED_LOW);
high_speed_set = false;
debug("Set lower SPI-frequency");
}
break;
default:
_dev->set_speed(AP_HAL::Device::SPEED_LOW);
high_speed_set = false;
debug("Set lower SPI-frequency");
debug("%s: wrong baudrate (%u) for SPI-driven device. setting default speed", __func__, b);
break;
}
_initialised = true;
}
int SPIUARTDriver::_write_fd(const uint8_t *buf, uint16_t size)
{
if (_external) {
return UARTDriver::_write_fd(buf,size);
}
if (!_dev->get_semaphore()->take_nonblocking()) {
return 0;
}
_dev->transfer_fullduplex(buf, _buffer, size);
_dev->get_semaphore()->give();
uint16_t ret = size;
/* Since all SPI-transactions are transfers we need update
* the _readbuf. I do believe there is a way to encapsulate
* this operation since it's the same as in the
* UARTDriver::write().
*/
_readbuf.write(_buffer, size);
return ret;
}
int SPIUARTDriver::_read_fd(uint8_t *buf, uint16_t n)
{
static uint8_t ff_stub[100] = {0xff};
if (_external) {
return UARTDriver::_read_fd(buf, n);
}
/* Make SPI transactions shorter. It can save SPI bus from keeping too
* long. It's essential for NavIO as MPU9250 is on the same bus and
* doesn't like to be waiting. Making transactions more frequent but shorter
* is a win.
*/
n = MIN(n, 100);
if (!_dev->get_semaphore()->take_nonblocking()) {
return 0;
}
_dev->transfer_fullduplex(ff_stub, buf, n);
_dev->get_semaphore()->give();
return n;
}
void SPIUARTDriver::_timer_tick(void)
{
if (_external) {
UARTDriver::_timer_tick();
return;
}
/* lower the update rate */
if (AP_HAL::micros() - _last_update_timestamp < 10000) {
return;
}
UARTDriver::_timer_tick();
_last_update_timestamp = AP_HAL::micros();
}