diff options
Diffstat (limited to 'os/hal/ports/KINETIS/LLD/ADCv1/hal_adc_lld.c')
| -rw-r--r-- | os/hal/ports/KINETIS/LLD/ADCv1/hal_adc_lld.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/os/hal/ports/KINETIS/LLD/ADCv1/hal_adc_lld.c b/os/hal/ports/KINETIS/LLD/ADCv1/hal_adc_lld.c new file mode 100644 index 0000000..847f424 --- /dev/null +++ b/os/hal/ports/KINETIS/LLD/ADCv1/hal_adc_lld.c @@ -0,0 +1,259 @@ +/*
+ ChibiOS - Copyright (C) 2014 Derek Mulcahy
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+/**
+ * @file ADCv1/hal_adc_lld.c
+ * @brief KINETIS ADC subsystem low level driver source.
+ *
+ * @addtogroup ADC
+ * @{
+ */
+
+#include "hal.h"
+
+#if HAL_USE_ADC || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver local definitions. */
+/*===========================================================================*/
+
+#define ADC_CHANNEL_MASK 0x1f
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/** @brief ADC1 driver identifier.*/
+#if KINETIS_ADC_USE_ADC0 || defined(__DOXYGEN__)
+ADCDriver ADCD1;
+#endif
+
+/*===========================================================================*/
+/* Driver local variables and types. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+
+static void calibrate(ADCDriver *adcp) {
+
+ /* Clock Divide by 8, Use Bus Clock Div 2 */
+ /* At 48MHz this results in ADCCLK of 48/8/2 == 3MHz */
+ adcp->adc->CFG1 = ADCx_CFG1_ADIV(ADCx_CFG1_ADIV_DIV_8) |
+ ADCx_CFG1_ADICLK(ADCx_CFG1_ADIVCLK_BUS_CLOCK_DIV_2);
+
+ /* Use software trigger and disable DMA etc. */
+ adcp->adc->SC2 = 0;
+
+ /* Enable Hardware Average, Average 32 Samples, Calibrate */
+ adcp->adc->SC3 = ADCx_SC3_AVGE |
+ ADCx_SC3_AVGS(ADCx_SC3_AVGS_AVERAGE_32_SAMPLES) |
+ ADCx_SC3_CAL;
+
+ /* FIXME: May take several ms. Use an interrupt instead of busy wait */
+ /* Wait for calibration completion */
+ while (!(adcp->adc->SC1A & ADCx_SC1n_COCO))
+ ;
+
+ uint16_t gain = ((adcp->adc->CLP0 + adcp->adc->CLP1 + adcp->adc->CLP2 +
+ adcp->adc->CLP3 + adcp->adc->CLP4 + adcp->adc->CLPS) / 2) | 0x8000;
+ adcp->adc->PG = gain;
+
+ gain = ((adcp->adc->CLM0 + adcp->adc->CLM1 + adcp->adc->CLM2 +
+ adcp->adc->CLM3 + adcp->adc->CLM4 + adcp->adc->CLMS) / 2) | 0x8000;
+ adcp->adc->MG = gain;
+
+}
+
+/*===========================================================================*/
+/* Driver interrupt handlers. */
+/*===========================================================================*/
+
+#if KINETIS_ADC_USE_ADC0 || defined(__DOXYGEN__)
+/**
+ * @brief ADC interrupt handler.
+ *
+ * @isr
+ */
+OSAL_IRQ_HANDLER(KINETIS_ADC0_IRQ_VECTOR) {
+ OSAL_IRQ_PROLOGUE();
+
+ ADCDriver *adcp = &ADCD1;
+
+ /* Disable Interrupt, Disable Channel */
+ adcp->adc->SC1A = ADCx_SC1n_ADCH(ADCx_SC1n_ADCH_DISABLED);
+
+ /* Read the sample into the buffer */
+ adcp->samples[adcp->current_index++] = adcp->adc->RA;
+
+ bool more = true;
+
+ /* At the end of the buffer then we may be finished */
+ if (adcp->current_index == adcp->number_of_samples) {
+ /* We are never finished in circular mode */
+ more = ADCD1.grpp->circular;
+
+ _adc_isr_full_code(&ADCD1);
+
+ adcp->current_index = 0;
+
+ }
+
+ if (more) {
+
+ /* Signal half completion in circular mode. */
+ if (ADCD1.grpp->circular &&
+ (adcp->current_index == (adcp->number_of_samples / 2))) {
+
+ _adc_isr_half_code(&ADCD1);
+ }
+
+ /* Skip to the next channel */
+ do {
+ adcp->current_channel = (adcp->current_channel + 1) & ADC_CHANNEL_MASK;
+ } while (((1 << adcp->current_channel) & adcp->grpp->channel_mask) == 0);
+
+ /* Enable Interrupt, Select the Channel */
+ adcp->adc->SC1A = ADCx_SC1n_AIEN | ADCx_SC1n_ADCH(adcp->current_channel);
+ }
+
+ OSAL_IRQ_EPILOGUE();
+}
+#endif
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Low level ADC driver initialization.
+ *
+ * @notapi
+ */
+void adc_lld_init(void) {
+
+#if KINETIS_ADC_USE_ADC0
+ /* Driver initialization.*/
+ adcObjectInit(&ADCD1);
+#endif
+
+ /* The shared vector is initialized on driver initialization and never
+ disabled.*/
+ nvicEnableVector(ADC0_IRQn, KINETIS_ADC_IRQ_PRIORITY);
+}
+
+/**
+ * @brief Configures and activates the ADC peripheral.
+ *
+ * @param[in] adcp pointer to the @p ADCDriver object
+ *
+ * @notapi
+ */
+void adc_lld_start(ADCDriver *adcp) {
+
+ /* If in stopped state then enables the ADC clock.*/
+ if (adcp->state == ADC_STOP) {
+ SIM->SCGC6 |= SIM_SCGC6_ADC0;
+
+#if KINETIS_ADC_USE_ADC0
+ if (&ADCD1 == adcp) {
+ adcp->adc = ADC0;
+ if (adcp->config->calibrate) {
+ calibrate(adcp);
+ }
+ }
+#endif /* KINETIS_ADC_USE_ADC0 */
+ }
+}
+
+/**
+ * @brief Deactivates the ADC peripheral.
+ *
+ * @param[in] adcp pointer to the @p ADCDriver object
+ *
+ * @notapi
+ */
+void adc_lld_stop(ADCDriver *adcp) {
+
+ /* If in ready state then disables the ADC clock.*/
+ if (adcp->state == ADC_READY) {
+ SIM->SCGC6 &= ~SIM_SCGC6_ADC0;
+
+#if KINETIS_ADC_USE_ADC0
+ if (&ADCD1 == adcp) {
+ /* Disable Interrupt, Disable Channel */
+ adcp->adc->SC1A = ADCx_SC1n_ADCH(ADCx_SC1n_ADCH_DISABLED);
+ }
+#endif
+ }
+}
+
+/**
+ * @brief Starts an ADC conversion.
+ *
+ * @param[in] adcp pointer to the @p ADCDriver object
+ *
+ * @notapi
+ */
+void adc_lld_start_conversion(ADCDriver *adcp) {
+ const ADCConversionGroup *grpp = adcp->grpp;
+
+ /* Enable the Bandgap Buffer if channel mask includes BANDGAP */
+ if (grpp->channel_mask & ADC_BANDGAP) {
+ PMC->REGSC |= PMC_REGSC_BGBE;
+ }
+
+ adcp->number_of_samples = adcp->depth * grpp->num_channels;
+ adcp->current_index = 0;
+
+ /* Skip to the next channel */
+ adcp->current_channel = 0;
+ while (((1 << adcp->current_channel) & grpp->channel_mask) == 0) {
+ adcp->current_channel = (adcp->current_channel + 1) & ADC_CHANNEL_MASK;
+ }
+
+ /* Set clock speed and conversion size */
+ adcp->adc->CFG1 = grpp->cfg1;
+
+ /* Set averaging */
+ adcp->adc->SC3 = grpp->sc3;
+
+ /* Enable Interrupt, Select Channel */
+ adcp->adc->SC1A = ADCx_SC1n_AIEN | ADCx_SC1n_ADCH(adcp->current_channel);
+}
+
+/**
+ * @brief Stops an ongoing conversion.
+ *
+ * @param[in] adcp pointer to the @p ADCDriver object
+ *
+ * @notapi
+ */
+void adc_lld_stop_conversion(ADCDriver *adcp) {
+ const ADCConversionGroup *grpp = adcp->grpp;
+
+ /* Disable the Bandgap buffer if channel mask includes BANDGAP */
+ if (grpp->channel_mask & ADC_BANDGAP) {
+ /* Clear BGBE, ACKISO is w1c, avoid setting */
+ PMC->REGSC &= ~(PMC_REGSC_BGBE | PMC_REGSC_ACKISO);
+ }
+
+}
+
+#endif /* HAL_USE_ADC */
+
+/** @} */
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