/**
 * Copyright (c) 2017 - 2018, 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
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 * 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.
 * 
 */
/** @file
 * @defgroup blinky_rtc_freertos_example_main main.c
 * @{
 * @ingroup blinky_rtc_freertos_example
 *
 * @brief Blinky FreeRTOS Example Application main file.
 *
 * This file contains the source code for a sample application using FreeRTOS to blink LEDs.
 *
 */

#include <stdbool.h>
#include <stdint.h>

#include "FreeRTOS.h"
#include "semphr.h"
#include "timers.h"
#include "bsp.h"
#include "nordic_common.h"
#include "nrf_drv_clock.h"
#include "sdk_errors.h"
#include "app_error.h"
#include "nrf_drv_rtc.h"


#if LEDS_NUMBER <= 2
#error "Board is not equipped with enough amount of LEDs"
#endif

/**
 * @brief RTC instance number used for blinking
 *
 */
#define BLINK_RTC 2

/**
 * @brief RTC compare channel used
 *
 */
#define BLINK_RTC_CC 0

/**
 * @brief Number of RTC ticks between interrupts
 */
#define BLINK_RTC_TICKS   (RTC_US_TO_TICKS(500000ULL, RTC_DEFAULT_CONFIG_FREQUENCY))

/**
 * @brief Reference to LED0 toggling FreeRTOS task.
 */
static TaskHandle_t  m_led_toggle_task_handle;

/**
 * @brief Semaphore set in RTC event
 */
static SemaphoreHandle_t m_led_semaphore;

/**
 * @brief RTC configuration
 */
static nrf_drv_rtc_config_t const m_rtc_config = NRF_DRV_RTC_DEFAULT_CONFIG;

/**
 * @brief RTC instance
 *
 * Instance of the RTC used for led blinking
 */
static nrf_drv_rtc_t const m_rtc = NRF_DRV_RTC_INSTANCE(BLINK_RTC);


static void blink_rtc_handler(nrf_drv_rtc_int_type_t int_type)
{
    BaseType_t yield_req = pdFALSE;
    ret_code_t err_code;
    bsp_board_led_invert(BSP_BOARD_LED_1);
    err_code = nrf_drv_rtc_cc_set(
        &m_rtc,
        BLINK_RTC_CC,
        (nrf_rtc_cc_get(m_rtc.p_reg, BLINK_RTC_CC) + BLINK_RTC_TICKS) & RTC_COUNTER_COUNTER_Msk,
        true);
    APP_ERROR_CHECK(err_code);

   /* The returned value may be safely ignored, if error is returned it only means that
    * the semaphore is already given (raised). */
   UNUSED_VARIABLE(xSemaphoreGiveFromISR(m_led_semaphore, &yield_req));
   portYIELD_FROM_ISR(yield_req);
}

/**
 * @brief LED0 task entry function.
 *
 * @param[in] pvParameter   Pointer that will be used as the parameter for the task.
 */
static void led_toggle_task_function (void * pvParameter)
{
    ret_code_t err_code;

    err_code = nrf_drv_rtc_init(&m_rtc, &m_rtc_config, blink_rtc_handler);
    APP_ERROR_CHECK(err_code);
    err_code = nrf_drv_rtc_cc_set(&m_rtc, BLINK_RTC_CC, BLINK_RTC_TICKS, true);
    APP_ERROR_CHECK(err_code);
    nrf_drv_rtc_enable(&m_rtc);

    m_led_semaphore = xSemaphoreCreateBinary();
    ASSERT(NULL != m_led_semaphore);

    UNUSED_PARAMETER(pvParameter);
    while (true)
    {
        bsp_board_led_invert(BSP_BOARD_LED_0);

        /* Wait for the event from the RTC */
        UNUSED_RETURN_VALUE(xSemaphoreTake(m_led_semaphore, portMAX_DELAY));
    }

    /* Tasks must be implemented to never return... */
}


int main(void)
{
    ret_code_t err_code;

    /* Initialize clock driver for better time accuracy in FREERTOS */
    err_code = nrf_drv_clock_init();
    APP_ERROR_CHECK(err_code);

    /* Configure LED-pins as outputs */
    bsp_board_init(BSP_INIT_LEDS);

    /* Create task for LED0 blinking with priority set to 2 */
    UNUSED_VARIABLE(xTaskCreate(led_toggle_task_function, "LED0", configMINIMAL_STACK_SIZE + 200, NULL, 2, &m_led_toggle_task_handle));

    /* Activate deep sleep mode */
    SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk;

    /* Start FreeRTOS scheduler. */
    vTaskStartScheduler();

    while (true)
    {
        ASSERT(false);
        /* FreeRTOS should not be here... FreeRTOS goes back to the start of stack
         * in vTaskStartScheduler function. */
    }
}

/**
 * @}
 */