tinySA/os/hal/platforms/AT91SAM7/adc_lld.h

304 lines
9.0 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006-2013 Giovanni Di Sirio
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.
*/
/*
This file has been contributed by:
Andrew Hannam aka inmarket.
*/
/**
* @file AT91SAM7/adc_lld.h
* @brief AT91SAM7 ADC subsystem low level driver header.
*
* @addtogroup ADC
* @{
*/
#ifndef _ADC_LLD_H_
#define _ADC_LLD_H_
#if HAL_USE_ADC || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver constants. */
/*===========================================================================*/
/**
* @name Trigger Sources
* @{
*/
#define ADC_TRIGGER_SOFTWARE 0x8000 /**< @brief Software Triggering - Can be combined with another value */
#define ADC_TRIGGER_TIMER 0x0001 /**< @brief TIO Timer Counter Channel */
#define ADC_TRIGGER_EXTERNAL 0x0002 /**< @brief External Trigger */
/** @} */
/*===========================================================================*/
/* 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 TRUE.
*/
#if !defined(ADC_USE_ADC1) || defined(__DOXYGEN__)
#define ADC_USE_ADC1 TRUE
#endif
/**
* @brief ADC1 Timer to use when a periodic conversion is requested.
* @details Should be set to 0..2
* @note The default is 0
*/
#if !defined(AT91_ADC1_TIMER) || defined(__DOXYGEN__)
#define AT91_ADC1_TIMER 0
#endif
/**
* @brief ADC1 Resolution.
* @details Either 8 or 10 bits
* @note The default is 10 bits.
*/
#if !defined(AT91_ADC1_RESOLUTION) || defined(__DOXYGEN__)
#define AT91_ADC1_RESOLUTION 10
#endif
/**
* @brief ADC1 Clock
* @details Maximum is 5MHz for 10bit or 8MHz for 8bit
* @note The default is calculated from AT91_ADC1_RESOLUTION to give the fastest possible ADCClock
*/
#if !defined(AT91_ADC1_CLOCK) || defined(__DOXYGEN__)
#if AT91_ADC1_RESOLUTION == 8
#define AT91_ADC1_CLOCK 8000000
#else
#define AT91_ADC1_CLOCK 5000000
#endif
#endif
/**
* @brief ADC1 Sample and Hold Time
* @details SHTM = RoundUp(ADCClock * SampleHoldTime). Range = RoundUp(ADCClock / 1,666,666) to 15
* @note Default corresponds to the minimum sample and hold time (600nS from the datasheet)
* @note Increasing the Sample Hold Time increases the ADC input impedance
*/
#if !defined(AT91_ADC1_SHTM) || defined(__DOXYGEN__)
#define AT91_ADC1_SHTM 0
#endif
#if AT91_ADC1_SHTM < ((AT91_ADC1_CLOCK+1666665)/1666666)
#undef AT91_ADC1_SHTM
#define AT91_ADC1_SHTM ((AT91_ADC1_CLOCK+1666665)/1666666)
#endif
#if AT91_ADC1_SHTM > 15
#undef AT91_ADC1_SHTM
#define AT91_ADC1_SHTM 15
#endif
/**
* @brief ADC interrupt priority level setting.
*/
#if !defined(AT91_ADC_IRQ_PRIORITY) || defined(__DOXYGEN__)
#define AT91_ADC_IRQ_PRIORITY (AT91C_AIC_PRIOR_HIGHEST - 2)
#endif
/** @} */
/*===========================================================================*/
/* Derived constants and error checks. */
/*===========================================================================*/
#if !defined(AT91_DMA_REQUIRED)
#define AT91_DMA_REQUIRED
#endif
/*===========================================================================*/
/* Driver data structures and types. */
/*===========================================================================*/
/**
* @brief ADC sample data type.
*/
#if AT91_ADC1_RESOLUTION == AT91C_ADC_LOWRES_8_BIT
typedef uint8_t adcsample_t;
#else
typedef uint16_t adcsample_t;
#endif
/**
* @brief Channels number in a conversion group.
*/
typedef uint16_t adc_channels_num_t;
/**
* @brief Possible ADC failure causes.
* @note Error codes are architecture dependent and should not relied
* upon.
*/
typedef enum {
ADC_ERR_OVERFLOW = 0, /**< ADC overflow condition. Something is not working fast enough. */
} adcerror_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 ADC error callback type.
*
* @param[in] adcp pointer to the @p ADCDriver object triggering the
* callback
* @param[in] err ADC error code
*/
typedef void (*adcerrorcallback_t)(ADCDriver *adcp, adcerror_t err);
/**
* @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_t 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;
/**
* @brief Error callback or @p NULL.
*/
adcerrorcallback_t error_cb;
/* End of the mandatory fields.*/
/**
* @brief Select the ADC Channels to read.
* @details The number of bits at logic level one in this register must
* be equal to the number in the @p num_channels field.
*/
uint16_t channelselects;
/**
* @brief Select how to trigger the conversion.
*/
uint16_t trigger;
/**
* @brief When in ADC_TRIGGER_TIMER trigger mode - what frequency?
*/
uint32_t frequency;
} ADCConversionGroup;
/**
* @brief Driver configuration structure.
* @note It could be empty on some architectures.
*/
typedef struct {
} 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 *thread;
#endif
#if ADC_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__)
#if CH_USE_MUTEXES || defined(__DOXYGEN__)
/**
* @brief Mutex protecting the peripheral.
*/
Mutex mutex;
#elif CH_USE_SEMAPHORES
Semaphore semaphore;
#endif
#endif /* ADC_USE_MUTUAL_EXCLUSION */
#if defined(ADC_DRIVER_EXT_FIELDS)
ADC_DRIVER_EXT_FIELDS
#endif
/* End of the mandatory fields.*/
};
/*===========================================================================*/
/* Driver macros. */
/*===========================================================================*/
/*===========================================================================*/
/* External declarations. */
/*===========================================================================*/
#if 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_ */
/** @} */