text: /**
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  /** @file
   *
   * @defgroup app_gpiote GPIOTE Handler
   * @{
   * @ingroup app_common
   *
   * @brief GPIOTE handler module.
   *
   * @details The GPIOTE handler allows several modules ("users") to share the GPIOTE interrupt,
   *          each user defining a set of pins able to generate events to the user.
   *          When a GPIOTE interrupt occurs, the GPIOTE interrupt handler will call the event handler
   *          of each user for which at least one of the pins generated an event.
   *
   *          The GPIOTE users are responsible for configuring all their corresponding pins, except
   *          the SENSE field, which should be initialized to GPIO_PIN_CNF_SENSE_Disabled.
   *          The SENSE field will be updated by the GPIOTE module when it is enabled or disabled,
   *          and also while it is enabled.
   *
   *          The module specifies on which pins events should be generated if the pin(s) goes
   *          from low->high or high->low or both directions.
   *
   * @note    Even if the application is using the @ref app_scheduler, the GPIOTE event handlers will
   *          be called directly from the GPIOTE interrupt handler.
   *
   * @warning If multiple users registers for the same pins the behavior for those pins are undefined.
   */
  
  #ifndef APP_GPIOTE_H__
  #define APP_GPIOTE_H__
  
  #include <stdint.h>
  #include <stdbool.h>
  #include "nrf.h"
  #include "app_error.h"
  #include "app_util.h"
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #define GPIOTE_USER_NODE_SIZE   ((4*sizeof(uint32_t)*GPIO_COUNT)+8)          /**< Size of app_gpiote.gpiote_user_t (only for use inside APP_GPIOTE_BUF_SIZE()). */
  
  /**@brief Compute number of bytes required to hold the GPIOTE data structures.
   *
   * @param[in]   MAX_USERS   Maximum number of GPIOTE users.
   *
   * @retval      Required buffer size (in bytes).
   */
  #define APP_GPIOTE_BUF_SIZE(MAX_USERS)  ((MAX_USERS) * GPIOTE_USER_NODE_SIZE)
  
  typedef uint8_t app_gpiote_user_id_t;
  
  /**@brief GPIOTE event handler type. */
  typedef void (*app_gpiote_event_handler_t)(uint32_t const * p_event_pins_low_to_high,
                                             uint32_t const * p_event_pins_high_to_low);
  
  /**@brief GPIOTE input event handler type. */
  typedef void (*app_gpiote_input_event_handler_t)(void);
  
  /**@brief Macro for initializing the GPIOTE module.
   *
   * @details It will handle dimensioning and allocation of the memory buffer required by the module,
   *          making sure that the buffer is correctly aligned.
   *
   * @param[in]   MAX_USERS   Maximum number of GPIOTE users.
   *
   * @note Since this macro allocates a buffer, it must only be called once (it is OK to call it
   *       several times as long as it is from the same location, e.g. to do a reinitialization).
   */
  /*lint -emacro(506, APP_GPIOTE_INIT) */ /* Suppress "Constant value Boolean */
  #define APP_GPIOTE_INIT(MAX_USERS)                                                                 \
      do                                                                                             \
      {                                                                                              \
          static uint32_t app_gpiote_buf[CEIL_DIV(APP_GPIOTE_BUF_SIZE(MAX_USERS), sizeof(uint32_t))];\
          uint32_t ERR_CODE = app_gpiote_init((MAX_USERS), app_gpiote_buf);                          \
          APP_ERROR_CHECK(ERR_CODE);                                                                 \
      } while (0)
  
  /**@brief Function for initializing the GPIOTE module.
   *
   * @note Normally initialization should be done using the APP_GPIOTE_INIT() macro, as that will
   *       allocate the buffer needed by the GPIOTE module (including aligning the buffer correctly).
   *
   * @param[in]   max_users               Maximum number of GPIOTE users.
   * @param[in]   p_buffer                Pointer to memory buffer for internal use in the app_gpiote
   *                                      module. The size of the buffer can be computed using the
   *                                      APP_GPIOTE_BUF_SIZE() macro. The buffer must be aligned to
   *                                      a 4 byte boundary.
   *
   * @retval      NRF_SUCCESS             Successful initialization.
   * @retval      NRF_ERROR_INVALID_PARAM Invalid parameter (buffer not aligned to a 4 byte
   *                                      boundary).
   */
  uint32_t app_gpiote_init(uint8_t max_users, void * p_buffer);
  
  /**@brief Function for registering a GPIOTE user.
   *
   * @param[out]  p_user_id               Id for the new GPIOTE user.
   * @param[in]   p_pins_low_to_high_mask Pointer to word array with mask defining which pins
   *                                      will generate events to this user when state is changed
   *                                      from low->high. Size of array depends on number of ports
   *                                      in the device.
   * @param[in]   p_pins_high_to_low_mask Pointer to word array with mask defining which pins
   *                                      will generate events to this user when state is changed
   *                                      from high->low. Size of array depends on number of ports
   *                                      in the device.
   * @param[in]   event_handler           Pointer to function to be executed when an event occurs.
   *
   * @retval      NRF_SUCCESS             Successful initialization.
   * @retval      NRF_ERROR_INVALID_PARAM Invalid parameter (buffer not aligned to a 4 byte boundary).
   * @retval      NRF_ERROR_INALID_STATE  If @ref app_gpiote_init has not been called on the GPIOTE
   *                                      module.
   * @retval      NRF_ERROR_NO_MEM        Returned if the application tries to register more users
   *                                      than defined when the GPIOTE module was initialized in
   *                                      @ref app_gpiote_init.
   */
  uint32_t app_gpiote_user_register(app_gpiote_user_id_t *     p_user_id,
                                    uint32_t const *           p_pins_low_to_high_mask,
                                    uint32_t const *           p_pins_high_to_low_mask,
                                    app_gpiote_event_handler_t event_handler);
  
  /**@brief Function for informing the GPIOTE module that the specified user wants to use the GPIOTE module.
   *
   * @param[in]   user_id                 Id of user to enable.
   *
   * @retval      NRF_SUCCESS             On success.
   * @retval      NRF_ERROR_INVALID_PARAM Invalid user_id provided, No a valid user.
   * @retval      NRF_ERROR_INALID_STATE  If @ref app_gpiote_init has not been called on the GPIOTE
   *                                      module.
   */
  uint32_t app_gpiote_user_enable(app_gpiote_user_id_t user_id);
  
  /**@brief Function for informing the GPIOTE module that the specified user is done using the GPIOTE module.
   *
   * @param[in]   user_id                   Id of user to enable.
   *
   * @retval      NRF_SUCCESS               On success.
   * @retval      NRF_ERROR_INVALID_PARAM   Invalid user_id provided, No a valid user.
   * @retval      NRF_ERROR_INALID_STATE    If @ref app_gpiote_init has not been called on the GPIOTE
   *                                        module.
   */
  uint32_t app_gpiote_user_disable(app_gpiote_user_id_t user_id);
  
  /**@brief Function for getting the state of the pins which are registered for the specified user.
   *
   * @param[in]   user_id         Id of user to check.
   * @param[out]  p_pins          Pointer to array of words with bit mask corresponding to the pins
   *                              configured to generate events to the specified user. All bits
   *                              corresponding to pins in the state 'high' will have value '1',
   *                              all others will have value '0'. Size of array depends on number
   *                              of ports in the device.
   *
   * @retval      NRF_SUCCESS               On success.
   * @retval      NRF_ERROR_INVALID_PARAM   Invalid user_id provided, No a valid user.
   * @retval      NRF_ERROR_INALID_STATE    If @ref app_gpiote_init has not been called on the GPIOTE
   *                                        module.
   */
  uint32_t app_gpiote_pins_state_get(app_gpiote_user_id_t user_id, uint32_t * p_pins);
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif // APP_GPIOTE_H__
  
  /** @} */
  