text: /* Copyright (c) 2015 Nordic Semiconductor. All Rights Reserved.
   *
   * The information contained herein is property of Nordic Semiconductor ASA.
   * Terms and conditions of usage are described in detail in NORDIC
   * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
   *
   * Licensees are granted free, non-transferable use of the information. NO
   * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
   * the file.
   *
   */
  
  #ifndef NRF_DRV_GPIOTE__
  #define NRF_DRV_GPIOTE__
  
  /**
   * @addtogroup nrf_gpiote GPIOTE abstraction and driver
   * @ingroup nrf_drivers
   * @brief GPIOTE APIs.
   * @defgroup nrf_drv_gpiote GPIOTE driver
   * @{
   * @ingroup nrf_gpiote
   * @brief GPIOTE driver for managing input and output pins.
   */
  
  #include "nrf_gpiote.h"
  #include "nrf_gpio.h"
  #include "sdk_errors.h"
  #include <stdint.h>
  #include <stdbool.h>
  #include "sdk_config.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**@brief Input pin configuration. */
  typedef struct
  {
      nrf_gpiote_polarity_t sense;      /**< Transition that triggers interrupt. */
      nrf_gpio_pin_pull_t   pull;       /**< Pulling mode. */
      bool                  is_watcher; /**< True when the input pin is tracking an output pin. */
      bool                  hi_accuracy;/**< True when high accuracy (IN_EVENT) is used. */
  } nrf_drv_gpiote_in_config_t;
  
  /**@brief Macro for configuring a pin to use a GPIO IN or PORT EVENT to detect low-to-high transition.
   * @details Set hi_accu to true to use IN_EVENT. */
  #define GPIOTE_CONFIG_IN_SENSE_LOTOHI(hi_accu)     \
      {                                            \
          .is_watcher = false,                     \
          .hi_accuracy = hi_accu,                  \
          .pull = NRF_GPIO_PIN_NOPULL,             \
          .sense = NRF_GPIOTE_POLARITY_LOTOHI,     \
      }
  
  /**@brief Macro for configuring a pin to use a GPIO IN or PORT EVENT to detect high-to-low transition.
   * @details Set hi_accu to true to use IN_EVENT. */
  #define GPIOTE_CONFIG_IN_SENSE_HITOLO(hi_accu)      \
      {                                            \
          .is_watcher = false,                     \
          .hi_accuracy = hi_accu,                  \
          .pull = NRF_GPIO_PIN_NOPULL,             \
          .sense = NRF_GPIOTE_POLARITY_HITOLO,     \
      }
  
  /**@brief Macro for configuring a pin to use a GPIO IN or PORT EVENT to detect any change on the pin.
   * @details Set hi_accu to true to use IN_EVENT.*/
  #define GPIOTE_CONFIG_IN_SENSE_TOGGLE(hi_accu)   \
      {                                            \
          .is_watcher = false,                     \
          .hi_accuracy = hi_accu,                  \
          .pull = NRF_GPIO_PIN_NOPULL,             \
          .sense = NRF_GPIOTE_POLARITY_TOGGLE,     \
      }
  
  /**@brief Output pin configuration. */
  typedef struct
  {
      nrf_gpiote_polarity_t action;    /**< Configuration of the pin task. */
      nrf_gpiote_outinit_t  init_state; /**< Initial state of the output pin. */
      bool                  task_pin;  /**< True if the pin is controlled by a GPIOTE task. */
  } nrf_drv_gpiote_out_config_t;
  
  /**@brief Macro for configuring a pin to use as output. GPIOTE is not used for the pin. */
  #define GPIOTE_CONFIG_OUT_SIMPLE(init_high)                                                        \
      {                                                                                              \
          .init_state = init_high ? NRF_GPIOTE_INITIAL_VALUE_HIGH : NRF_GPIOTE_INITIAL_VALUE_LOW,    \
          .task_pin = false,                                                                         \
      }
  
  /**@brief Macro for configuring a pin to use the GPIO OUT TASK to change the state from high to low.
   * @details The task will clear the pin. Therefore, the pin is set initially.  */
  #define GPIOTE_CONFIG_OUT_TASK_LOW                                                                 \
      {                                                                                              \
          .init_state = NRF_GPIOTE_INITIAL_VALUE_HIGH,                                               \
          .task_pin   = true,                                                                        \
          .action     = NRF_GPIOTE_POLARITY_HITOLO,                                                  \
      }
  
  /**@brief Macro for configuring a pin to use the GPIO OUT TASK to change the state from low to high.
   * @details The task will set the pin. Therefore, the pin is cleared initially.  */
  #define GPIOTE_CONFIG_OUT_TASK_HIGH                                                                \
      {                                                                                              \
          .init_state = NRF_GPIOTE_INITIAL_VALUE_LOW,                                                \
          .task_pin   = true,                                                                        \
          .action     = NRF_GPIOTE_POLARITY_LOTOHI,                                                  \
      }
  
  /**@brief Macro for configuring a pin to use the GPIO OUT TASK to toggle the pin state.
   * @details The initial pin state must be provided.  */
  #define GPIOTE_CONFIG_OUT_TASK_TOGGLE(init_high)                                                   \
      {                                                                                              \
          .init_state = init_high ? NRF_GPIOTE_INITIAL_VALUE_HIGH : NRF_GPIOTE_INITIAL_VALUE_LOW,    \
          .task_pin   = true,                                                                        \
          .action     = NRF_GPIOTE_POLARITY_TOGGLE,                                                  \
      }
  
  /** @brief Pin. */
  typedef uint32_t nrf_drv_gpiote_pin_t;
  
  /**
   * @brief Pin event handler prototype.
   * @param pin    Pin that triggered this event.
   * @param action Action that lead to triggering this event.
   */
  typedef void (*nrf_drv_gpiote_evt_handler_t)(nrf_drv_gpiote_pin_t pin, nrf_gpiote_polarity_t action);
  
  /**
   * @brief Function for initializing the GPIOTE module.
   *
   * @details Only static configuration is supported to prevent the shared
   * resource being customized by the initiator.
   *
   * @retval    NRF_SUCCESS If initialization was successful.
   * @retval    NRF_ERROR_INVALID_STATE If the driver was already initialized.
   */
  ret_code_t nrf_drv_gpiote_init(void);
  
  /**
   * @brief Function for checking if the GPIOTE module is initialized.
   *
   * @details The GPIOTE module is a shared module. Therefore, you should check if
   * the module is already initialized and skip initialization if it is.
   *
   * @retval    true  If the module is already initialized.
   * @retval    false If the module is not initialized.
   */
  bool nrf_drv_gpiote_is_init(void);
  
  /**
   * @brief Function for uninitializing the GPIOTE module.
   */
  void nrf_drv_gpiote_uninit(void);
  
  /**
   * @brief Function for initializing a GPIOTE output pin.
   * @details The output pin can be controlled by the CPU or by PPI. The initial
   * configuration specifies which mode is used. If PPI mode is used, the driver
   * attempts to allocate one of the available GPIOTE channels. If no channel is
   * available, an error is returned.
   *
   * @param[in] pin       Pin.
   * @param[in] p_config  Initial configuration.
   *
   * @retval NRF_SUCCESS             If initialization was successful.
   * @retval NRF_ERROR_INVALID_STATE If the driver is not initialized or the pin is already used.
   * @retval NRF_ERROR_NO_MEM        If no GPIOTE channel is available.
   */
  ret_code_t nrf_drv_gpiote_out_init(nrf_drv_gpiote_pin_t pin,
                                     nrf_drv_gpiote_out_config_t const * p_config);
  
  /**
   * @brief Function for uninitializing a GPIOTE output pin.
   * @details The driver frees the GPIOTE channel if the output pin was using one.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_out_uninit(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for setting a GPIOTE output pin.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_out_set(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for clearing a GPIOTE output pin.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_out_clear(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for toggling a GPIOTE output pin.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_out_toggle(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for enabling a GPIOTE output pin task.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_out_task_enable(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for disabling a GPIOTE output pin task.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_out_task_disable(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for getting the address of a configurable GPIOTE task.
   *
   * @param[in] pin       Pin.
   *
   * @return Address of OUT task.
   */
  uint32_t nrf_drv_gpiote_out_task_addr_get(nrf_drv_gpiote_pin_t pin);
  
  #if defined(GPIOTE_FEATURE_SET_PRESENT)
  /**
   * @brief Function for getting the address of a configurable GPIOTE task.
   *
   * @param[in] pin       Pin.
   *
   * @return Address of SET task.
   */
  uint32_t nrf_drv_gpiote_set_task_addr_get(nrf_drv_gpiote_pin_t pin);
  #endif // defined(GPIOTE_FEATURE_SET_PRESENT)
  
  #if defined(GPIOTE_FEATURE_CLR_PRESENT)
  /**
   * @brief Function for getting the address of a configurable GPIOTE task.
   *
   * @param[in] pin       Pin.
   *
   * @return Address of CLR task.
   */
  uint32_t nrf_drv_gpiote_clr_task_addr_get(nrf_drv_gpiote_pin_t pin);
  #endif // defined(GPIOTE_FEATURE_CLR_PRESENT)
  
  /**
   * @brief Function for initializing a GPIOTE input pin.
   * @details The input pin can act in two ways:
   * - lower accuracy but low power (high frequency clock not needed)
   * - higher accuracy (high frequency clock required)
   *
   * The initial configuration specifies which mode is used.
   * If high-accuracy mode is used, the driver attempts to allocate one
   * of the available GPIOTE channels. If no channel is
   * available, an error is returned.
   * In low accuracy mode SENSE feature is used. In this case only one active pin
   * can be detected at a time. It can be worked around by setting all of the used
   * low accuracy pins to toggle mode.
   * For more information about SENSE functionality, refer to Product Specification.
   *
   * @param[in] pin       Pin.
   * @param[in] p_config    Initial configuration.
   * @param[in] evt_handler User function to be called when the configured transition occurs.
   *
   * @retval NRF_SUCCESS             If initialization was successful.
   * @retval NRF_ERROR_INVALID_STATE If the driver is not initialized or the pin is already used.
   * @retval NRF_ERROR_NO_MEM        If no GPIOTE channel is available.
   */
  ret_code_t nrf_drv_gpiote_in_init(nrf_drv_gpiote_pin_t pin,
                                    nrf_drv_gpiote_in_config_t const * p_config,
                                    nrf_drv_gpiote_evt_handler_t evt_handler);
  
  /**
   * @brief Function for uninitializing a GPIOTE input pin.
   * @details The driver frees the GPIOTE channel if the input pin was using one.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_in_uninit(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for enabling sensing of a GPIOTE input pin.
   *
   * @details If the input pin is configured as high-accuracy pin, the function
   * enables an IN_EVENT. Otherwise, the function enables the GPIO sense mechanism.
   * Note that a PORT event is shared between multiple pins, therefore the
   * interrupt is always enabled.
   *
   * @param[in] pin       Pin.
   * @param[in] int_enable  True to enable the interrupt. Always valid for a high-accuracy pin.
   */
  void nrf_drv_gpiote_in_event_enable(nrf_drv_gpiote_pin_t pin, bool int_enable);
  
  /**
   * @brief Function for disabling a GPIOTE input pin.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_in_event_disable(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for checking if a GPIOTE input pin is set.
   *
   * @param[in] pin       Pin.
   * @retval    true If the input pin is set.
   * @retval    false If the input pin is not set.
   */
  bool nrf_drv_gpiote_in_is_set(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for getting the address of a GPIOTE input pin event.
   * @details If the pin is configured to use low-accuracy mode, the address of the PORT event is returned.
   *
   * @param[in] pin       Pin.
   */
  uint32_t nrf_drv_gpiote_in_event_addr_get(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for forcing a specific state on the pin configured as task.
   *
   * @param[in] pin       Pin.
   * @param[in] state     Pin state.
   */
  void nrf_drv_gpiote_out_task_force(nrf_drv_gpiote_pin_t pin, uint8_t state);
  
  /**
   * @brief Function for triggering the task OUT manually.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_out_task_trigger(nrf_drv_gpiote_pin_t pin);
  
  #ifdef NRF52
  /**
   * @brief Function for triggering the task SET manually.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_set_task_trigger(nrf_drv_gpiote_pin_t pin);
  
  /**
   * @brief Function for triggering the task CLR manually.
   *
   * @param[in] pin       Pin.
   */
  void nrf_drv_gpiote_clr_task_trigger(nrf_drv_gpiote_pin_t pin);
  #endif
  
  /**
   *@}
   **/
  
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif //NRF_DRV_GPIOTE__
  