/flight/pios/stm32f0x/pios_adc.c
C | 391 lines | 228 code | 57 blank | 106 comment | 24 complexity | 3bef62634dbf6eccdfc6483096f831d3 MD5 | raw file
- /**
- ******************************************************************************
- * @addtogroup PIOS PIOS Core hardware abstraction layer
- * @{
- * @addtogroup PIOS_ADC ADC Functions
- * @brief STM32 ADC PIOS interface
- * @{
- *
- * @file pios_adc.c
- * @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2012.
- * @brief Analog to Digital converstion routines
- * @see The GNU Public License (GPL) Version 3
- *****************************************************************************/
- /*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
- #include "pios.h"
- #ifdef PIOS_INCLUDE_ADC
- #include <pios_adc_priv.h>
- // Private types
- enum pios_adc_dev_magic {
- PIOS_ADC_DEV_MAGIC = 0x58375124,
- };
- struct pios_adc_dev {
- const struct pios_adc_cfg *cfg;
- ADCCallback callback_function;
- #if defined(PIOS_INCLUDE_FREERTOS)
- xQueueHandle data_queue;
- #endif
- volatile int16_t *valid_data_buffer;
- volatile uint8_t adc_oversample;
- uint8_t dma_block_size;
- uint16_t dma_half_buffer_size;
- #if defined(PIOS_INCLUDE_ADC)
- int16_t fir_coeffs[PIOS_ADC_MAX_SAMPLES + 1] __attribute__((aligned(4)));
- volatile int16_t raw_data_buffer[PIOS_ADC_MAX_SAMPLES] __attribute__((aligned(4))); // Double buffer that DMA just used
- float downsampled_buffer[PIOS_ADC_NUM_CHANNELS] __attribute__((aligned(4)));
- #endif
- enum pios_adc_dev_magic magic;
- };
- float PIOS_ADC_PinGetVolt(uint32_t pin)
- {
- return ((float)PIOS_ADC_PinGet(pin)) * PIOS_ADC_VOLTAGE_SCALE;
- }
- #if defined(PIOS_INCLUDE_FREERTOS)
- struct pios_adc_dev *pios_adc_dev;
- #endif
- // Private functions
- void PIOS_ADC_downsample_data();
- static struct pios_adc_dev *PIOS_ADC_Allocate();
- static bool PIOS_ADC_validate(struct pios_adc_dev *);
- /* Local Variables */
- static GPIO_TypeDef *ADC_GPIO_PORT[PIOS_ADC_NUM_PINS] = PIOS_ADC_PORTS;
- static const uint32_t ADC_GPIO_PIN[PIOS_ADC_NUM_PINS] = PIOS_ADC_PINS;
- static const uint32_t ADC_CHANNEL[PIOS_ADC_NUM_PINS] = PIOS_ADC_CHANNELS;
- static ADC_TypeDef *ADC_MAPPING[PIOS_ADC_NUM_PINS] = PIOS_ADC_MAPPING;
- static const uint32_t ADC_CHANNEL_MAPPING[PIOS_ADC_NUM_PINS] = PIOS_ADC_CHANNEL_MAPPING;
- static bool PIOS_ADC_validate(struct pios_adc_dev *dev)
- {
- if (dev == NULL) {
- return false;
- }
- return dev->magic == PIOS_ADC_DEV_MAGIC;
- }
- #if defined(PIOS_INCLUDE_FREERTOS)
- static struct pios_adc_dev *PIOS_ADC_Allocate()
- {
- struct pios_adc_dev *adc_dev;
- adc_dev = (struct pios_adc_dev *)pvPortMalloc(sizeof(*adc_dev));
- if (!adc_dev) {
- return NULL;
- }
- adc_dev->magic = PIOS_ADC_DEV_MAGIC;
- return adc_dev;
- }
- #else
- #error Not implemented
- #endif
- /**
- * @brief Initialise the ADC Peripheral, configure to run at the max oversampling
- */
- int32_t PIOS_ADC_Init(const struct pios_adc_cfg *cfg)
- {
- pios_adc_dev = PIOS_ADC_Allocate();
- if (pios_adc_dev == NULL) {
- return -1;
- }
- pios_adc_dev->cfg = cfg;
- pios_adc_dev->callback_function = NULL;
- #if defined(PIOS_INCLUDE_FREERTOS)
- pios_adc_dev->data_queue = NULL;
- #endif
- /* Setup analog pins */
- GPIO_InitTypeDef GPIO_InitStructure;
- GPIO_StructInit(&GPIO_InitStructure);
- GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
- GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
- /* Enable each ADC pin in the array */
- for (int32_t i = 0; i < PIOS_ADC_NUM_PINS; i++) {
- GPIO_InitStructure.GPIO_Pin = ADC_GPIO_PIN[i];
- GPIO_Init(ADC_GPIO_PORT[i], &GPIO_InitStructure);
- }
- PIOS_ADC_Config(PIOS_ADC_MAX_OVERSAMPLING);
- return 0;
- }
- /**
- * @brief Configure the ADC to run at a fixed oversampling
- * @param[in] oversampling the amount of oversampling to run at
- */
- void PIOS_ADC_Config(uint32_t oversampling)
- {
- pios_adc_dev->adc_oversample = (oversampling > PIOS_ADC_MAX_OVERSAMPLING) ? PIOS_ADC_MAX_OVERSAMPLING : oversampling;
- ADC_DeInit(ADC1);
- ADC_DeInit(ADC2);
- /* Disable interrupts */
- DMA_ITConfig(pios_adc_dev->cfg->dma.rx.channel, pios_adc_dev->cfg->dma.irq.flags, DISABLE);
- /* Enable ADC clocks */
- PIOS_ADC_CLOCK_FUNCTION;
- /* Map channels to conversion slots depending on the channel selection mask */
- for (int32_t i = 0; i < PIOS_ADC_NUM_PINS; i++) {
- ADC_RegularChannelConfig(ADC_MAPPING[i], ADC_CHANNEL[i],
- ADC_CHANNEL_MAPPING[i],
- PIOS_ADC_SAMPLE_TIME);
- }
- #if (PIOS_ADC_USE_TEMP_SENSOR)
- ADC_TempSensorVrefintCmd(ENABLE);
- ADC_RegularChannelConfig(PIOS_ADC_TEMP_SENSOR_ADC, ADC_Channel_16,
- PIOS_ADC_TEMP_SENSOR_ADC_CHANNEL,
- PIOS_ADC_SAMPLE_TIME);
- #endif
- // return
- /* Configure ADCs */
- ADC_InitTypeDef ADC_InitStructure;
- ADC_StructInit(&ADC_InitStructure);
- ADC_InitStructure.ADC_Mode = ADC_Mode_RegSimult;
- ADC_InitStructure.ADC_ScanConvMode = ENABLE;
- ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
- ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
- ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
- ADC_InitStructure.ADC_NbrOfChannel = ((PIOS_ADC_NUM_CHANNELS + 1) >> 1);
- ADC_Init(ADC1, &ADC_InitStructure);
- #if (PIOS_ADC_USE_ADC2)
- ADC_Init(ADC2, &ADC_InitStructure);
- /* Enable ADC2 external trigger conversion (to synch with ADC1) */
- ADC_ExternalTrigConvCmd(ADC2, ENABLE);
- #endif
- RCC_ADCCLKConfig(PIOS_ADC_ADCCLK);
- /* Enable ADC1->DMA request */
- ADC_DMACmd(ADC1, ENABLE);
- /* ADC1 calibration */
- ADC_Cmd(ADC1, ENABLE);
- ADC_ResetCalibration(ADC1);
- while (ADC_GetResetCalibrationStatus(ADC1)) {
- ;
- }
- ADC_StartCalibration(ADC1);
- while (ADC_GetCalibrationStatus(ADC1)) {
- ;
- }
- #if (PIOS_ADC_USE_ADC2)
- /* ADC2 calibration */
- ADC_Cmd(ADC2, ENABLE);
- ADC_ResetCalibration(ADC2);
- while (ADC_GetResetCalibrationStatus(ADC2)) {
- ;
- }
- ADC_StartCalibration(ADC2);
- while (ADC_GetCalibrationStatus(ADC2)) {
- ;
- }
- #endif
- /* This makes sure we have an even number of transfers if using ADC2 */
- pios_adc_dev->dma_block_size = ((PIOS_ADC_NUM_CHANNELS + PIOS_ADC_USE_ADC2) >> PIOS_ADC_USE_ADC2) << PIOS_ADC_USE_ADC2;
- pios_adc_dev->dma_half_buffer_size = pios_adc_dev->dma_block_size * pios_adc_dev->adc_oversample;
- /* Configure DMA channel */
- DMA_InitTypeDef dma_init = pios_adc_dev->cfg->dma.rx.init;
- dma_init.DMA_MemoryBaseAddr = (uint32_t)&pios_adc_dev->raw_data_buffer[0];
- dma_init.DMA_MemoryInc = DMA_MemoryInc_Enable;
- dma_init.DMA_BufferSize = pios_adc_dev->dma_half_buffer_size; /* x2 for double buffer /2 for 32-bit xfr */
- DMA_Init(pios_adc_dev->cfg->dma.rx.channel, &dma_init);
- DMA_Cmd(pios_adc_dev->cfg->dma.rx.channel, ENABLE);
- /* Trigger interrupt when for half conversions too to indicate double buffer */
- DMA_ITConfig(pios_adc_dev->cfg->dma.rx.channel, DMA_IT_TC, ENABLE);
- DMA_ITConfig(pios_adc_dev->cfg->dma.rx.channel, DMA_IT_HT, ENABLE);
- /* Configure DMA interrupt */
- NVIC_Init(&pios_adc_dev->cfg->dma.irq.init);
- /* Finally start initial conversion */
- ADC_SoftwareStartConvCmd(ADC1, ENABLE);
- /* Use simple averaging filter for now */
- for (int32_t i = 0; i < pios_adc_dev->adc_oversample; i++) {
- pios_adc_dev->fir_coeffs[i] = 1;
- }
- pios_adc_dev->fir_coeffs[pios_adc_dev->adc_oversample] = pios_adc_dev->adc_oversample;
- /* Enable DMA1 clock */
- RCC_AHBPeriphClockCmd(pios_adc_dev->cfg->dma.ahb_clk, ENABLE);
- }
- /**
- * Returns value of an ADC Pin
- * \param[in] pin number
- * \return ADC pin value - resolution depends on the selected oversampling rate
- * \return -1 if pin doesn't exist
- */
- int32_t PIOS_ADC_PinGet(uint32_t pin)
- {
- /* Check if pin exists */
- if (pin >= PIOS_ADC_NUM_CHANNELS) {
- return -1;
- }
- /* Return last conversion result */
- return pios_adc_dev->downsampled_buffer[pin];
- }
- /**
- * @brief Set a callback function that is executed whenever
- * the ADC double buffer swaps
- */
- void PIOS_ADC_SetCallback(ADCCallback new_function)
- {
- pios_adc_dev->callback_function = new_function;
- }
- #if defined(PIOS_INCLUDE_FREERTOS)
- /**
- * @brief Register a queue to add data to when downsampled
- */
- void PIOS_ADC_SetQueue(xQueueHandle data_queue)
- {
- pios_adc_dev->data_queue = data_queue;
- }
- #endif
- /**
- * @brief Return the address of the downsampled data buffer
- */
- float *PIOS_ADC_GetBuffer(void)
- {
- return pios_adc_dev->downsampled_buffer;
- }
- /**
- * @brief Return the address of the raw data data buffer
- */
- int16_t *PIOS_ADC_GetRawBuffer(void)
- {
- return (int16_t *)pios_adc_dev->valid_data_buffer;
- }
- /**
- * @brief Return the amount of over sampling
- */
- uint8_t PIOS_ADC_GetOverSampling(void)
- {
- return pios_adc_dev->adc_oversample;
- }
- /**
- * @brief Set the fir coefficients. Takes as many samples as the
- * current filter order plus one (normalization)
- *
- * @param new_filter Array of adc_oversampling floats plus one for the
- * filter coefficients
- */
- void PIOS_ADC_SetFIRCoefficients(float *new_filter)
- {
- // Less than or equal to get normalization constant
- for (int i = 0; i <= pios_adc_dev->adc_oversample; i++) {
- pios_adc_dev->fir_coeffs[i] = new_filter[i];
- }
- }
- /**
- * @brief Downsample the data for each of the channels then call
- * callback function if installed
- */
- void PIOS_ADC_downsample_data()
- {
- uint16_t chan;
- uint16_t sample;
- float *downsampled_buffer = &pios_adc_dev->downsampled_buffer[0];
- for (chan = 0; chan < PIOS_ADC_NUM_CHANNELS; chan++) {
- int32_t sum = 0;
- for (sample = 0; sample < pios_adc_dev->adc_oversample; sample++) {
- sum += pios_adc_dev->valid_data_buffer[chan + sample * pios_adc_dev->dma_block_size] * pios_adc_dev->fir_coeffs[sample];
- }
- downsampled_buffer[chan] = (float)sum / pios_adc_dev->fir_coeffs[pios_adc_dev->adc_oversample];
- }
- #if defined(PIOS_INCLUDE_FREERTOS)
- if (pios_adc_dev->data_queue) {
- static portBASE_TYPE xHigherPriorityTaskWoken;
- xQueueSendFromISR(pios_adc_dev->data_queue, pios_adc_dev->downsampled_buffer, &xHigherPriorityTaskWoken);
- portEND_SWITCHING_ISR(xHigherPriorityTaskWoken);
- }
- #endif
- if (pios_adc_dev->callback_function) {
- pios_adc_dev->callback_function(pios_adc_dev->downsampled_buffer);
- }
- }
- /**
- * @brief Interrupt for half and full buffer transfer
- *
- * This interrupt handler swaps between the two halfs of the double buffer to make
- * sure the ahrs uses the most recent data. Only swaps data when AHRS is idle, but
- * really this is a pretense of a sanity check since the DMA engine is consantly
- * running in the background. Keep an eye on the ekf_too_slow variable to make sure
- * it's keeping up.
- */
- void PIOS_ADC_DMA_Handler(void)
- {
- if (!PIOS_ADC_validate(pios_adc_dev)) {
- return;
- }
- if (DMA_GetFlagStatus(pios_adc_dev->cfg->full_flag /*DMA1_IT_TC1*/)) { // whole double buffer filled
- pios_adc_dev->valid_data_buffer = &pios_adc_dev->raw_data_buffer[pios_adc_dev->dma_half_buffer_size];
- DMA_ClearFlag(pios_adc_dev->cfg->full_flag);
- PIOS_ADC_downsample_data();
- } else if (DMA_GetFlagStatus(pios_adc_dev->cfg->half_flag /*DMA1_IT_HT1*/)) {
- pios_adc_dev->valid_data_buffer = &pios_adc_dev->raw_data_buffer[0];
- DMA_ClearFlag(pios_adc_dev->cfg->half_flag);
- PIOS_ADC_downsample_data();
- } else {
- // This should not happen, probably due to transfer errors
- DMA_ClearFlag(pios_adc_dev->cfg->dma.irq.flags /*DMA1_FLAG_GL1*/);
- }
- }
- #endif /* PIOS_INCLUDE_ADC */
- /**
- * @}
- * @}
- */