text: /**
   * \file
   *
   * \brief SAM RTC Driver (Count Interrupt Mode)
   *
   * Copyright (C) 2013-2015 Atmel Corporation. All rights reserved.
   *
   * \asf_license_start
   *
   * \page License
   *
   * 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 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. The name of Atmel may not be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * 4. This software may only be redistributed and used in connection with an
   *    Atmel microcontroller product.
   *
   * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
   * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
   *
   * \asf_license_stop
   *
   */
  /*
   * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
   */
  #include "rtc_count_interrupt.h"
  
  extern struct rtc_module *_rtc_instance[RTC_INST_NUM];
  
  /**
   * \brief Registers callback for the specified callback type
   *
   * Associates the given callback function with the
   * specified callback type.
   * To enable the callback, the \ref rtc_count_enable_callback function
   * must be used.
   *
   * \param[in,out]  module  Pointer to the software instance struct
   * \param[in]  callback      Pointer to the function desired for the specified
   *                           callback
   * \param[in]  callback_type Callback type to register
   *
   * \return                        Status of registering callback.
   * \retval STATUS_OK              Registering was done successfully
   * \retval STATUS_ERR_INVALID_ARG If trying to register a callback not available
   */
  enum status_code rtc_count_register_callback(
  		struct rtc_module *const module,
  		rtc_count_callback_t callback,
  		enum rtc_count_callback callback_type)
  {
  
  	enum status_code status = STATUS_OK;
  
  	/* Overflow callback */
  	if (callback_type == RTC_COUNT_CALLBACK_OVERFLOW) {
  		status = STATUS_OK;
  	} else {
  		/* Make sure callback type can be registered */
  		switch (module->mode) {
  		case RTC_COUNT_MODE_32BIT:
  			/* Check sanity for 32-bit mode. */
  			if (callback_type > RTC_NUM_OF_COMP32) {
  				status = STATUS_ERR_INVALID_ARG;
  			}
  
  			break;
  		case RTC_COUNT_MODE_16BIT:
  			/* Check sanity for 16-bit mode. */
  			if (callback_type > RTC_NUM_OF_COMP16) {
  				status = STATUS_ERR_INVALID_ARG;
  			}
  			break;
  		default:
  			status = STATUS_ERR_INVALID_ARG;
  		}
  	}
  
  	if (status == STATUS_OK) {
  		/* Register callback */
  		module->callbacks[callback_type] = callback;
  		/* Set corresponding bit to set callback as registered */
  		module->registered_callback |= (1 << callback_type);
  	}
  
  	return status;
  }
  
  /**
   * \brief Unregisters callback for the specified callback type
   *
   * When called, the currently registered callback for the given callback type
   * will be removed.
   *
   * \param[in,out]  module  Pointer to the software instance struct
   * \param[in]     callback_type  Specifies the callback type to unregister
   *
   * \return                        Status of unregistering callback.
   * \retval STATUS_OK              Unregistering was done successfully
   * \retval STATUS_ERR_INVALID_ARG If trying to unregister a callback not available
   */
  enum status_code rtc_count_unregister_callback(
  		struct rtc_module *const module,
  		enum rtc_count_callback callback_type)
  {
  	enum status_code status = STATUS_OK;
  
  	/* Overflow callback */
  	if (callback_type == RTC_COUNT_CALLBACK_OVERFLOW) {
  		status = STATUS_OK;
  	} else {
  		/* Make sure callback type can be unregistered */
  		switch (module->mode) {
  		case RTC_COUNT_MODE_32BIT:
  			/* Check sanity for 32-bit mode. */
  			if (callback_type > RTC_NUM_OF_COMP32) {
  				status = STATUS_ERR_INVALID_ARG;
  			}
  			break;
  		case RTC_COUNT_MODE_16BIT:
  			/* Check sanity for 16-bit mode. */
  			if (callback_type > RTC_NUM_OF_COMP16) {
  				status = STATUS_ERR_INVALID_ARG;
  			}
  			break;
  		default:
  			status = STATUS_ERR_INVALID_ARG;
  		}
  	}
  	if (status == STATUS_OK) {
  		/* Unregister callback */
  		module->callbacks[callback_type] = NULL;
  
  		/* Clear corresponding bit to set callback as unregistered */
  		module->registered_callback &= ~(1 << callback_type);
  	}
  	return status;
  }
  
  /**
   * \brief Enables callback
   *
   * Enables the callback specified by the callback_type.
   *
   * \param[in,out]  module  Pointer to the software instance struct
   * \param[in]     callback_type Callback type to enable
   */
  void rtc_count_enable_callback(
  		struct rtc_module *const module,
  		enum rtc_count_callback callback_type)
  {
  	/* Sanity check arguments */
  	Assert(module);
  	Assert(module->hw);
  
  	Rtc *const rtc_module = module->hw;
  
  	if (callback_type == RTC_COUNT_CALLBACK_OVERFLOW) {
  		rtc_module->MODE0.INTENSET.reg = RTC_MODE0_INTFLAG_OVF;
  	} else {
  		rtc_module->MODE0.INTENSET.reg = RTC_MODE1_INTFLAG_CMP(1 << callback_type);
  	}
  	/* Mark callback as enabled. */
  	module->enabled_callback |= (1 << callback_type);
  }
  
  /**
   * \brief Disables callback
   *
   * Disables the callback specified by the callback_type.
   *
   * \param[in,out]  module  Pointer to the software instance struct
   * \param[in]     callback_type Callback type to disable
   */
  void rtc_count_disable_callback(
  		struct rtc_module *const module,
  		enum rtc_count_callback callback_type)
  {
  	/* Sanity check arguments */
  	Assert(module);
  	Assert(module->hw);
  
  	Rtc *const rtc_module = module->hw;
  
  	/* Disable interrupt */
  	if (callback_type == RTC_COUNT_CALLBACK_OVERFLOW) {
  		rtc_module->MODE0.INTENCLR.reg = RTC_MODE0_INTFLAG_OVF;
  	} else {
  		rtc_module->MODE0.INTENCLR.reg = RTC_MODE1_INTFLAG_CMP(1 << callback_type);
  	}
  
  	/* Mark callback as disabled. */
  	module->enabled_callback &= ~(1 << callback_type);
  }
  
  /**
   * \internal Interrupt handler for RTC
   *
   * \param [in] instance_index  Default value 0
   */
  static void _rtc_interrupt_handler(const uint32_t instance_index)
  {
  	struct rtc_module *module = _rtc_instance[instance_index];
  
  	Rtc *const rtc_module = module->hw;
  
  	/* Combine callback registered and enabled masks */
  	uint16_t callback_mask = module->enabled_callback;
  	callback_mask &= module->registered_callback;
  
  	/* Read and mask interrupt flag register */
  	uint16_t interrupt_status = rtc_module->MODE0.INTFLAG.reg;
  	interrupt_status &= rtc_module->MODE0.INTENSET.reg;
  
  	if (interrupt_status & RTC_MODE0_INTFLAG_OVF) {
  		/* Overflow interrupt */
  		if (callback_mask & (1 << RTC_COUNT_CALLBACK_OVERFLOW)) {
  			module->callbacks[RTC_COUNT_CALLBACK_OVERFLOW]();
  		}
  
  		/* Clear interrupt flag */
  		rtc_module->MODE0.INTFLAG.reg = RTC_MODE0_INTFLAG_OVF;
  
  	} else if (interrupt_status & RTC_MODE1_INTFLAG_CMP(1 << 0)) {
  		/* Compare 0 interrupt */
  		if (callback_mask & (1 << RTC_COUNT_CALLBACK_COMPARE_0)) {
  			module->callbacks[RTC_COUNT_CALLBACK_COMPARE_0]();
  		}
  		/* Clear interrupt flag */
  		rtc_module->MODE0.INTFLAG.reg = RTC_MODE1_INTFLAG_CMP(1 << 0);
  
  	} else if (interrupt_status & RTC_MODE1_INTFLAG_CMP(1 << 1)) {
  		#if (RTC_NUM_OF_COMP16 > 1) || defined(__DOXYGEN__)
  		/* Compare 1 interrupt */
  		if (callback_mask & (1 << RTC_COUNT_CALLBACK_COMPARE_1)) {
  			module->callbacks[RTC_COUNT_CALLBACK_COMPARE_1]();
  		}
  		/* Clear interrupt flag */
  		rtc_module->MODE0.INTFLAG.reg = RTC_MODE1_INTFLAG_CMP(1 << 1);
  		#endif
  
  	} else if (interrupt_status & RTC_MODE1_INTFLAG_CMP(1 << 2)) {
  		#if (RTC_NUM_OF_COMP16 > 2)	|| defined(__DOXYGEN__)
  		/* Compare 2 interrupt */
  		if (callback_mask & (1 << RTC_COUNT_CALLBACK_COMPARE_2)) {
  			module->callbacks[RTC_COUNT_CALLBACK_COMPARE_2]();
  		}
  		/* Clear interrupt flag */
  		rtc_module->MODE0.INTFLAG.reg = RTC_MODE1_INTFLAG_CMP(1 << 2);
  		#endif
  
  	} else if (interrupt_status & RTC_MODE1_INTFLAG_CMP(1 << 3)) {
  		#if (RTC_NUM_OF_COMP16 > 3)	|| defined(__DOXYGEN__)
  		/* Compare 3 interrupt */
  		if (callback_mask & (1 << RTC_COUNT_CALLBACK_COMPARE_3)) {
  			module->callbacks[RTC_COUNT_CALLBACK_COMPARE_3]();
  		}
  		/* Clear interrupt flag */
  		rtc_module->MODE0.INTFLAG.reg = RTC_MODE1_INTFLAG_CMP(1 << 3);
  		#endif
  
  	} else if (interrupt_status & RTC_MODE1_INTFLAG_CMP(1 << 4)) {
  		#if (RTC_NUM_OF_COMP16 > 4) || defined(__DOXYGEN__)
  		/* Compare 4 interrupt */
  		if (callback_mask & (1 << RTC_COUNT_CALLBACK_COMPARE_4)) {
  			module->callbacks[RTC_COUNT_CALLBACK_COMPARE_4]();
  		}
  		/* Clear interrupt flag */
  		rtc_module->MODE0.INTFLAG.reg = RTC_MODE1_INTFLAG_CMP(1 << 4);
  		#endif
  
  	} else if (interrupt_status & RTC_MODE1_INTFLAG_CMP(1 << 5)) {
  		#if (RTC_NUM_OF_COMP16 > 5) || defined(__DOXYGEN__)
  		/* Compare 5 interrupt */
  		if (callback_mask & (1 << RTC_COUNT_CALLBACK_COMPARE_5)) {
  			module->callbacks[RTC_COUNT_CALLBACK_COMPARE_5]();
  		}
  		/* Clear interrupt flag */
  		rtc_module->MODE0.INTFLAG.reg = RTC_MODE1_INTFLAG_CMP(1 << 5);
  		#endif
  	}
  }
  
  /**
   * \internal ISR handler for RTC
   */
  #if (RTC_INST_NUM == 1)
  void RTC_Handler(void)
  {
  	_rtc_interrupt_handler(0);
  }
  #elif (RTC_INST_NUM > 1)
  #  define _RTC_INTERRUPT_HANDLER(n, unused) \
  		void RTC##n##_Handler(void) \
  		{ \
  			_rtc_interrupt_handler(n); \
  		}
  
  MREPEAT(RTC_INST_NUM, _RTC_INTERRUPT_HANDLER, ~)
  #endif /* (RTC_INST_NUM > 1) */