From 2e554f3ef5e1e3d7b6d04457cee27dd79618e345 Mon Sep 17 00:00:00 2001
From: Stephen Caudle <stephen@caudle.info>
Date: Mon, 31 Aug 2015 23:16:06 -0400
Subject: Add ADC driver for nRF51
---
os/hal/ports/NRF51/NRF51822/adc_lld.c | 226 +++++++++++++++++++++++++++++++
os/hal/ports/NRF51/NRF51822/adc_lld.h | 229 ++++++++++++++++++++++++++++++++
os/hal/ports/NRF51/NRF51822/platform.mk | 3 +-
3 files changed, 457 insertions(+), 1 deletion(-)
create mode 100644 os/hal/ports/NRF51/NRF51822/adc_lld.c
create mode 100644 os/hal/ports/NRF51/NRF51822/adc_lld.h
(limited to 'os/hal/ports')
diff --git a/os/hal/ports/NRF51/NRF51822/adc_lld.c b/os/hal/ports/NRF51/NRF51822/adc_lld.c
new file mode 100644
index 0000000..0c28cb0
--- /dev/null
+++ b/os/hal/ports/NRF51/NRF51822/adc_lld.c
@@ -0,0 +1,226 @@
+/*
+ Copyright (C) 2015 Stephen Caudle
+
+ 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 NRF51Fx22/adc_lld.c
+ * @brief NRF51Fx22 ADC subsystem low level driver source.
+ *
+ * @addtogroup ADC
+ * @{
+ */
+
+#include "hal.h"
+
+#if HAL_USE_ADC || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver local definitions. */
+/*===========================================================================*/
+#define ADC_CHANNEL_MASK 0x7
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/** @brief ADC1 driver identifier.*/
+#if NRF51_ADC_USE_ADC1 || defined(__DOXYGEN__)
+ADCDriver ADCD1;
+#endif
+
+/*===========================================================================*/
+/* Driver local variables and types. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+
+static void adc_lld_config_next_channel(ADCDriver *adcp, uint32_t config) {
+
+ /* Default to all analog input pins disabled */
+ config &= ~ADC_CONFIG_PSEL_Msk;
+
+ if (adcp->grpp->channel_mask) {
+ /* Skip to the next channel */
+ while (((1 << adcp->current_channel) & adcp->grpp->channel_mask) == 0)
+ adcp->current_channel = (adcp->current_channel + 1) & ADC_CHANNEL_MASK;
+ config |= (((1 << adcp->current_channel) << ADC_CONFIG_PSEL_Pos) & ADC_CONFIG_PSEL_Msk);
+ }
+
+ /* Setup analog input pin select and user config values */
+ adcp->adc->CONFIG = config;
+}
+
+/*===========================================================================*/
+/* Driver interrupt handlers. */
+/*===========================================================================*/
+
+#if NRF51_ADC_USE_ADC1 || defined(__DOXYGEN__)
+/**
+ * @brief ADC interrupt handler.
+ *
+ * @isr
+ */
+OSAL_IRQ_HANDLER(Vector5C) {
+
+ ADCDriver *adcp = &ADCD1;
+ NRF_ADC_Type *adc = adcp->adc;
+ bool more = true;
+
+ OSAL_IRQ_PROLOGUE();
+
+ /* Clear the ADC event */
+ adc->EVENTS_END = 0;
+
+ /* Read the sample into the buffer */
+ adcp->samples[adcp->current_index++] = adc->RESULT;
+
+ /* At the end of the buffer then we may be finished */
+ if (adcp->current_index == adcp->number_of_samples) {
+ _adc_isr_full_code(adcp);
+
+ adcp->current_index = 0;
+
+ /* We are never finished in circular mode */
+ more = adcp->grpp->circular;
+ }
+
+ if (more) {
+
+ /* Signal half completion in circular mode. */
+ if (adcp->grpp->circular &&
+ (adcp->current_index == (adcp->number_of_samples / 2))) {
+
+ _adc_isr_half_code(adcp);
+ }
+
+ /* Skip to the next channel */
+ adcp->current_channel = (adcp->current_channel + 1) & ADC_CHANNEL_MASK;
+ adc_lld_config_next_channel(adcp, adcp->adc->CONFIG);
+ adcp->adc->TASKS_START = 1;
+ } else {
+ adc_lld_stop_conversion(adcp);
+ }
+
+ OSAL_IRQ_EPILOGUE();
+}
+#endif
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Low level ADC driver initialization.
+ *
+ * @notapi
+ */
+void adc_lld_init(void) {
+
+#if NRF51_ADC_USE_ADC1
+ /* Driver initialization.*/
+ adcObjectInit(&ADCD1);
+ ADCD1.adc = NRF_ADC;
+#endif
+}
+
+/**
+ * @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 configures and enables the ADC. */
+ if (adcp->state == ADC_STOP) {
+#if NRF51_ADC_USE_ADC1
+ if (&ADCD1 == adcp) {
+
+ adcp->adc->INTENSET = ADC_INTENSET_END_Enabled << ADC_INTENSET_END_Pos;
+ nvicEnableVector(ADC_IRQn, NRF51_ADC_IRQ_PRIORITY);
+ }
+#endif /* NRF51_ADC_USE_ADC1 */
+ }
+}
+
+/**
+ * @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 and analog part.*/
+ if (adcp->state == ADC_READY) {
+
+#if NRF51_ADC_USE_ADC1
+ if (&ADCD1 == adcp)
+
+ nvicDisableVector(ADC_IRQn);
+ adcp->adc->INTENCLR = ADC_INTENCLR_END_Clear << ADC_INTENCLR_END_Pos;
+ adc_lld_stop_conversion(adcp);
+#endif
+ }
+}
+
+/**
+ * @brief Starts an ADC conversion.
+ *
+ * @param[in] adcp pointer to the @p ADCDriver object
+ *
+ * @notapi
+ */
+void adc_lld_start_conversion(ADCDriver *adcp) {
+
+ NRF_ADC_Type *adc = adcp->adc;
+
+ adcp->number_of_samples = adcp->depth * adcp->grpp->num_channels;
+ adcp->current_index = 0;
+
+ /* At least one sample must be configured */
+ osalDbgAssert(adcp->number_of_samples, "must configure at least one sample");
+
+ /* Skip to the next channel */
+ adcp->current_channel = 0;
+ adc_lld_config_next_channel(adcp, adcp->grpp->cfg);
+
+ /* Enable and start the conversion */
+ adc->ENABLE = ADC_ENABLE_ENABLE_Enabled << ADC_ENABLE_ENABLE_Pos;
+ adc->TASKS_START = 1;
+}
+
+/**
+ * @brief Stops an ongoing conversion.
+ *
+ * @param[in] adcp pointer to the @p ADCDriver object
+ *
+ * @notapi
+ */
+void adc_lld_stop_conversion(ADCDriver *adcp) {
+
+ NRF_ADC_Type *adc = adcp->adc;
+
+ adc->TASKS_STOP = 1;
+ adc->ENABLE = ADC_ENABLE_ENABLE_Disabled << ADC_ENABLE_ENABLE_Pos;
+}
+
+#endif /* HAL_USE_ADC */
+
+/** @} */
diff --git a/os/hal/ports/NRF51/NRF51822/adc_lld.h b/os/hal/ports/NRF51/NRF51822/adc_lld.h
new file mode 100644
index 0000000..52d8e78
--- /dev/null
+++ b/os/hal/ports/NRF51/NRF51822/adc_lld.h
@@ -0,0 +1,229 @@
+/*
+ Copyright (C) 2015 Stephen Caudle
+
+ 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 NRF51x22/adc_lld.h
+ * @brief NRF51x22 ADC subsystem low level driver header.
+ *
+ * @addtogroup ADC
+ * @{
+ */
+
+#ifndef _ADC_LLD_H_
+#define _ADC_LLD_H_
+
+#if HAL_USE_ADC || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver constants. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver pre-compile time settings. */
+/*===========================================================================*/
+
+/**
+ * @name Configuration options
+ * @{
+ */
+/**
+ * @brief ADC1 driver enable switch.
+ * @details If set to @p TRUE the support for ADC1 is included.
+ * @note The default is @p FALSE.
+ */
+#if !defined(NRF51_ADC_USE_ADC1) || defined(__DOXYGEN__)
+#define NRF51_ADC_USE_ADC1 FALSE
+#endif
+
+/**
+ * @brief ADC interrupt priority level setting.
+ */
+#if !defined(NRF51_ADC_IRQ_PRIORITY) || defined(__DOXYGEN__)
+#define NRF51_ADC_IRQ_PRIORITY 2
+#endif
+
+/** @} */
+
+/*===========================================================================*/
+/* Derived constants and error checks. */
+/*===========================================================================*/
+
+#if !NRF51_ADC_USE_ADC1
+#error "ADC driver activated but no ADC peripheral assigned"
+#endif
+
+#if NRF51_ADC_USE_ADC1 && \
+ !OSAL_IRQ_IS_VALID_PRIORITY(NRF51_ADC_IRQ_PRIORITY)
+#error "Invalid IRQ priority assigned to ADC1"
+#endif
+
+/*===========================================================================*/
+/* Driver data structures and types. */
+/*===========================================================================*/
+
+/**
+ * @brief ADC sample data type.
+ */
+typedef uint16_t adcsample_t;
+
+/**
+ * @brief Channels number in a conversion group.
+ */
+typedef uint8_t adc_channels_num_t;
+
+/**
+ * @brief Type of a structure representing an ADC driver.
+ */
+typedef struct ADCDriver ADCDriver;
+
+/**
+ * @brief ADC notification callback type.
+ *
+ * @param[in] adcp pointer to the @p ADCDriver object triggering the
+ * callback
+ * @param[in] buffer pointer to the most recent samples data
+ * @param[in] n number of buffer rows available starting from @p buffer
+ */
+typedef void (*adccallback_t)(ADCDriver *adcp, adcsample_t *buffer, size_t n);
+
+/**
+ * @brief Conversion group configuration structure.
+ * @details This implementation-dependent structure describes a conversion
+ * operation.
+ * @note The use of this configuration structure requires knowledge of
+ * STM32 ADC cell registers interface, please refer to the STM32
+ * reference manual for details.
+ */
+typedef struct {
+ /**
+ * @brief Enables the circular buffer mode for the group.
+ */
+ bool circular;
+ /**
+ * @brief Number of the analog channels belonging to the conversion group.
+ */
+ adc_channels_num_t num_channels;
+ /**
+ * @brief Callback function associated to the group or @p NULL.
+ */
+ adccallback_t end_cb;
+ /* End of the mandatory fields.*/
+ /**
+ * @brief Bitmask of channels for ADC conversion.
+ */
+ uint32_t channel_mask;
+ /**
+ * @brief ADC CONFIG register details.
+ * @note All the required bits must be defined into this field.
+ */
+ uint32_t cfg;
+} ADCConversionGroup;
+
+/**
+ * @brief Driver configuration structure.
+ * @note It could be empty on some architectures.
+ */
+typedef struct {
+ uint32_t dummy;
+} ADCConfig;
+
+/**
+ * @brief Structure representing an ADC driver.
+ */
+struct ADCDriver {
+ /**
+ * @brief Driver state.
+ */
+ adcstate_t state;
+ /**
+ * @brief Current configuration data.
+ */
+ const ADCConfig *config;
+ /**
+ * @brief Current samples buffer pointer or @p NULL.
+ */
+ adcsample_t *samples;
+ /**
+ * @brief Current samples buffer depth or @p 0.
+ */
+ size_t depth;
+ /**
+ * @brief Current conversion group pointer or @p NULL.
+ */
+ const ADCConversionGroup *grpp;
+#if ADC_USE_WAIT || defined(__DOXYGEN__)
+ /**
+ * @brief Waiting thread.
+ */
+ thread_reference_t thread;
+#endif
+#if ADC_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__)
+ /**
+ * @brief Mutex protecting the peripheral.
+ */
+ mutex_t mutex;
+#endif /* ADC_USE_MUTUAL_EXCLUSION */
+#if defined(ADC_DRIVER_EXT_FIELDS)
+ ADC_DRIVER_EXT_FIELDS
+#endif
+ /* End of the mandatory fields.*/
+ /**
+ * @brief Pointer to the ADCx registers block.
+ */
+ NRF_ADC_Type *adc;
+ /**
+ * @brief Number of samples expected.
+ */
+ size_t number_of_samples;
+ /**
+ * @brief Current position in the buffer.
+ */
+ size_t current_index;
+ /**
+ * @brief Current channel index into group channel_mask.
+ */
+ size_t current_channel;
+};
+
+/*===========================================================================*/
+/* Driver macros. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* External declarations. */
+/*===========================================================================*/
+
+#if NRF51_ADC_USE_ADC1 && !defined(__DOXYGEN__)
+extern ADCDriver ADCD1;
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+ void adc_lld_init(void);
+ void adc_lld_start(ADCDriver *adcp);
+ void adc_lld_stop(ADCDriver *adcp);
+ void adc_lld_start_conversion(ADCDriver *adcp);
+ void adc_lld_stop_conversion(ADCDriver *adcp);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* HAL_USE_ADC */
+
+#endif /* _ADC_LLD_H_ */
+
+/** @} */
diff --git a/os/hal/ports/NRF51/NRF51822/platform.mk b/os/hal/ports/NRF51/NRF51822/platform.mk
index 09bb083..3fc8342 100644
--- a/os/hal/ports/NRF51/NRF51822/platform.mk
+++ b/os/hal/ports/NRF51/NRF51822/platform.mk
@@ -7,7 +7,8 @@ PLATFORMSRC = ${CHIBIOS}/os/hal/ports/common/ARMCMx/nvic.c \
${CHIBIOS_CONTRIB}/os/hal/ports/NRF51/NRF51822/spi_lld.c \
${CHIBIOS_CONTRIB}/os/hal/ports/NRF51/NRF51822/ext_lld_isr.c \
${CHIBIOS_CONTRIB}/os/hal/ports/NRF51/NRF51822/ext_lld.c \
- ${CHIBIOS_CONTRIB}/os/hal/ports/NRF51/NRF51822/i2c_lld.c
+ ${CHIBIOS_CONTRIB}/os/hal/ports/NRF51/NRF51822/i2c_lld.c \
+ ${CHIBIOS_CONTRIB}/os/hal/ports/NRF51/NRF51822/adc_lld.c
# Required include directories
PLATFORMINC = ${CHIBIOS}/os/hal/ports/common/ARMCMx \
--
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