nrf_drv_rtc.h

/**
 * Copyright (c) 2014 - 2017, Nordic Semiconductor ASA
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 * 
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 * 
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 * 
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 * 
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 */
#ifndef NRF_DRV_RTC_H
#define NRF_DRV_RTC_H


#include "sdk_config.h"
#include "nordic_common.h"
#include "nrf_drv_common.h"
#include "nrf_rtc.h"
#include "sdk_errors.h"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @addtogroup nrf_rtc RTC HAL and driver
 * @ingroup nrf_drivers
 * @brief Real timer counter (RTC) APIs.
 * @details The RTC HAL provides basic APIs for accessing the registers of the real time counter (RTC).
 * The RTC driver provides APIs on a higher level.
 *
 * @defgroup nrf_drv_rtc RTC driver
 * @{
 * @ingroup nrf_rtc
 * @brief Real timer counter (RTC) driver.
 */

/**@brief Macro to convert microseconds into ticks. */
#define RTC_US_TO_TICKS(us,freq) ((us * freq) / 1000000)

/**
 * @enum nrf_drv_rtc_int_type_t
 * @brief RTC driver interrupt types.
 */
typedef enum
{
    NRF_DRV_RTC_INT_COMPARE0 = 0, /**< Interrupt from COMPARE0 event. */
    NRF_DRV_RTC_INT_COMPARE1 = 1, /**< Interrupt from COMPARE1 event. */
    NRF_DRV_RTC_INT_COMPARE2 = 2, /**< Interrupt from COMPARE2 event. */
    NRF_DRV_RTC_INT_COMPARE3 = 3, /**< Interrupt from COMPARE3 event. */
    NRF_DRV_RTC_INT_TICK     = 4, /**< Interrupt from TICK event. */
    NRF_DRV_RTC_INT_OVERFLOW = 5  /**< Interrupt from OVERFLOW event. */
} nrf_drv_rtc_int_type_t;

/**@brief RTC driver instance  structure. */
typedef struct
{
    NRF_RTC_Type  * p_reg;            /**< Pointer to instance register set. */
    IRQn_Type       irq;              /**< Instance IRQ ID. */
    uint8_t         instance_id;      /**< Instance index. */
    uint8_t         cc_channel_count; /**< Number of capture/compare channels. */
} nrf_drv_rtc_t;

#define RTC0_INSTANCE_INDEX 0
#define RTC1_INSTANCE_INDEX RTC0_INSTANCE_INDEX+RTC0_ENABLED
#define RTC2_INSTANCE_INDEX RTC1_INSTANCE_INDEX+RTC1_ENABLED

/**@brief Macro for creating RTC driver instance.*/
#define NRF_DRV_RTC_INSTANCE(id)                           \
{                                                          \
    .p_reg            = CONCAT_2(NRF_RTC, id),             \
    .irq              = CONCAT_3(RTC, id, _IRQn),          \
    .instance_id      = CONCAT_3(RTC, id, _INSTANCE_INDEX),\
    .cc_channel_count = NRF_RTC_CC_CHANNEL_COUNT(id),      \
}

/**@brief RTC driver instance configuration structure. */
typedef struct
{
    uint16_t prescaler;          /**< Prescaler. */
    uint8_t  interrupt_priority; /**< Interrupt priority. */
    uint8_t  tick_latency;       /**< Maximum length of interrupt handler in ticks (max 7.7 ms). */
    bool     reliable;           /**< Reliable mode flag. */
} nrf_drv_rtc_config_t;

/**@brief RTC instance default configuration. */
#define NRF_DRV_RTC_DEFAULT_CONFIG                                                               \
{                                                                                                \
    .prescaler          = RTC_FREQ_TO_PRESCALER(RTC_DEFAULT_CONFIG_FREQUENCY),                   \
    .interrupt_priority = RTC_DEFAULT_CONFIG_IRQ_PRIORITY,                                       \
    .reliable           = RTC_DEFAULT_CONFIG_RELIABLE,                                           \
    .tick_latency       = RTC_US_TO_TICKS(NRF_MAXIMUM_LATENCY_US, RTC_DEFAULT_CONFIG_FREQUENCY), \
}

/**@brief RTC driver instance handler type. */
typedef void (*nrf_drv_rtc_handler_t)(nrf_drv_rtc_int_type_t int_type);

/**@brief Function for initializing the RTC driver instance.
 *
 * After initialization, the instance is in power off state.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 * @param[in]  p_config           Initial configuration. Default configuration used if NULL.
 * @param[in]  handler            User's event handler.
 *
 * @retval     NRF_SUCCESS               If successfully initialized.
 * @retval     NRF_ERROR_INVALID_PARAM   If no handler was provided.
 * @retval     NRF_ERROR_INVALID_STATE   If the instance is already initialized.
 */
ret_code_t nrf_drv_rtc_init(nrf_drv_rtc_t const * const p_instance,
                            nrf_drv_rtc_config_t const * p_config,
                            nrf_drv_rtc_handler_t handler);

/**@brief Function for uninitializing the RTC driver instance.
 *
 * After uninitialization, the instance is in idle state. The hardware should return to the state
 *       before initialization. The function asserts if the instance is in idle state.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 */
void nrf_drv_rtc_uninit(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for enabling the RTC driver instance.
 *
 * @note Function asserts if instance is enabled.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 */
void nrf_drv_rtc_enable(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for disabling the RTC driver instance.
 *
 * @note Function asserts if instance is disabled.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 */
void nrf_drv_rtc_disable(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for setting a compare channel.
 *
 * The function asserts if the instance is not initialized or if the channel parameter is
 *       wrong. The function powers on the instance if the instance was in power off state.
 *
 * The driver is not entering a critical section when configuring RTC, which means that it can be
 *       preempted for a certain amount of time. When the driver was preempted and the value to be set
 *       is short in time, there is a risk that the driver sets a compare value that is
 *       behind. If RTCn_CONFIG_RELIABLE is 1 for the given instance, the Reliable mode handles that case.
 *       However, to detect if the requested value is behind, this mode makes the following assumptions:
 *        -  The maximum preemption time in ticks (8 - bit value) is known and is less than 7.7 ms
 *         (for prescaler = 0, RTC frequency 32 kHz).
 *        -  The requested absolute compare value is not bigger than (0x00FFFFFF) - tick_latency. It is
 *         the user's responsibility to ensure that.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 * @param[in]  channel            One of the instance's channels.
 * @param[in]  val                Absolute value to be set in the compare register.
 * @param[in]  enable_irq         True to enable the interrupt. False to disable the interrupt.
 *
 * @retval     NRF_SUCCESS         If the procedure was successful.
 * @retval     NRF_ERROR_TIMEOUT   If the compare was not set because the request value is behind the current counter
 *                                 value. This error can only be reported if RTCn_CONFIG_RELIABLE = 1.
 */
ret_code_t nrf_drv_rtc_cc_set(nrf_drv_rtc_t const * const p_instance,
                              uint32_t channel,
                              uint32_t val,
                              bool enable_irq);

/**@brief Function for disabling a channel.
 *
 * This function disables channel events and channel interrupts. The function asserts if the instance is not
 *       initialized or if the channel parameter is wrong.
 *
 * @param[in]  p_instance          Pointer to the driver instance structure.
 * @param[in]  channel             One of the instance's channels.
 *
 * @retval     NRF_SUCCESS         If the procedure was successful.
 * @retval     NRF_ERROR_TIMEOUT   If an interrupt was pending on the requested channel.
 */
ret_code_t nrf_drv_rtc_cc_disable(nrf_drv_rtc_t const * const p_instance, uint32_t channel);

/**@brief Function for enabling tick.
 *
 * This function enables the tick event and optionally the interrupt. The function asserts if the instance is not
 *       powered on.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 * @param[in]  enable_irq         True to enable the interrupt. False to disable the interrupt.
 */
void nrf_drv_rtc_tick_enable(nrf_drv_rtc_t const * const p_instance, bool enable_irq);

/**@brief Function for disabling tick.
 *
 * This function disables the tick event and interrupt.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 */
void nrf_drv_rtc_tick_disable(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for enabling overflow.
 *
 * This function enables the overflow event and optionally the interrupt. The function asserts if the instance is
 *       not powered on.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 * @param[in]  enable_irq         True to enable the interrupt. False to disable the interrupt.
 */
void nrf_drv_rtc_overflow_enable(nrf_drv_rtc_t const * const p_instance, bool enable_irq);

/**@brief Function for disabling overflow.
 *
 * This function disables the overflow event and interrupt.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 */
void nrf_drv_rtc_overflow_disable(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for getting the maximum relative ticks value that can be set in the compare channel.
 *
 * When a SoftDevice is used, it occupies the highest level interrupt, so that the application code can be
 *       interrupted at any moment for a certain period of time. If Reliable mode is enabled, the provided
 *       maximum latency is taken into account and the return value is smaller than the RTC counter
 *       resolution. If Reliable mode is disabled, the return value equals the counter resolution.
 *
 * @param[in]  p_instance  Pointer to the driver instance structure.
 *
 * @retval     ticks         Maximum ticks value.
 */
uint32_t nrf_drv_rtc_max_ticks_get(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for disabling all instance interrupts.
  *
 * @param[in]  p_instance          Pointer to the driver instance structure.
 * @param[in]  p_mask              Pointer to the location where the mask is filled.
 */
__STATIC_INLINE void nrf_drv_rtc_int_disable(nrf_drv_rtc_t const * const p_instance,
                                             uint32_t * p_mask);

/**@brief Function for enabling instance interrupts.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 * @param[in]  mask               Mask of interrupts to enable.
 */
__STATIC_INLINE void nrf_drv_rtc_int_enable(nrf_drv_rtc_t const * const p_instance, uint32_t mask);

/**@brief Function for retrieving the current counter value.
 *
 * This function asserts if the instance is not powered on or if p_val is NULL.
 *
 * @param[in]  p_instance    Pointer to the driver instance structure.
 *
 * @retval     value         Counter value.
 */
__STATIC_INLINE uint32_t nrf_drv_rtc_counter_get(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for clearing the counter value.
 *
 * This function asserts if the instance is not powered on.
 *
 * @param[in]  p_instance         Pointer to the driver instance structure.
 */
__STATIC_INLINE void nrf_drv_rtc_counter_clear(nrf_drv_rtc_t const * const p_instance);

/**@brief Function for returning a requested task address for the RTC driver instance.
 *
 * This function asserts if the output pointer is NULL. The task address can be used by the PPI module.
 *
 * @param[in]  p_instance         Pointer to the instance.
 * @param[in]  task                One of the peripheral tasks.
 *
 * @retval     Address of task register.
 */
__STATIC_INLINE uint32_t nrf_drv_rtc_task_address_get(nrf_drv_rtc_t const * const p_instance,
                                                      nrf_rtc_task_t task);

/**@brief Function for returning a requested event address for the RTC driver instance.
 *
 * This function asserts if the output pointer is NULL. The event address can be used by the PPI module.
 *
 * @param[in]  p_instance          Pointer to the driver instance structure.
 * @param[in]  event               One of the peripheral events.
 *
 * @retval     Address of event register.
 */
__STATIC_INLINE uint32_t nrf_drv_rtc_event_address_get(nrf_drv_rtc_t const * const p_instance,
                                                       nrf_rtc_event_t event);
#ifndef SUPPRESS_INLINE_IMPLEMENTATION

__STATIC_INLINE void nrf_drv_rtc_int_disable(nrf_drv_rtc_t const * const p_instance,
                                                 uint32_t * p_mask)
{
    *p_mask = nrf_rtc_int_get(p_instance->p_reg);
    nrf_rtc_int_disable(p_instance->p_reg, NRF_RTC_INT_TICK_MASK |
                                           NRF_RTC_INT_OVERFLOW_MASK |
                                           NRF_RTC_INT_COMPARE0_MASK |
                                           NRF_RTC_INT_COMPARE1_MASK |
                                           NRF_RTC_INT_COMPARE2_MASK |
                                           NRF_RTC_INT_COMPARE3_MASK);
}

__STATIC_INLINE void nrf_drv_rtc_int_enable(nrf_drv_rtc_t const * const p_instance, uint32_t mask)
{
    nrf_rtc_int_enable(p_instance->p_reg, mask);
}

__STATIC_INLINE uint32_t nrf_drv_rtc_counter_get(nrf_drv_rtc_t const * const p_instance)
{
    return nrf_rtc_counter_get(p_instance->p_reg);
}

__STATIC_INLINE void nrf_drv_rtc_counter_clear(nrf_drv_rtc_t const * const p_instance)
{
    nrf_rtc_task_trigger(p_instance->p_reg,NRF_RTC_TASK_CLEAR);
}

__STATIC_INLINE uint32_t nrf_drv_rtc_task_address_get(nrf_drv_rtc_t const * const p_instance,
                                                      nrf_rtc_task_t task)
{
    return nrf_rtc_task_address_get(p_instance->p_reg, task);
}

__STATIC_INLINE uint32_t nrf_drv_rtc_event_address_get(nrf_drv_rtc_t const * const p_instance,
                                                       nrf_rtc_event_t event)
{
    return nrf_rtc_event_address_get(p_instance->p_reg, event);
}
#endif /* SUPPRESS_INLINE_IMPLEMENTATION */

/**
 *@}
 **/

#ifdef __cplusplus
}
#endif

#endif /* NRF_DRV_RTC_H */