app_gpiote.h

00001 /* Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
00002  *
00003  * The information contained herein is property of Nordic Semiconductor ASA.
00004  * Terms and conditions of usage are described in detail in NORDIC
00005  * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
00006  *
00007  * Licensees are granted free, non-transferable use of the information. NO
00008  * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
00009  * the file.
00010  *
00011  */
00012 
00013 /** @file
00014  *
00015  * @defgroup app_gpiote GPIOTE Handler
00016  * @{
00017  * @ingroup app_common
00018  *
00019  * @brief GPIOTE handler module.
00020  *
00021  * @details The GPIOTE handler allows several modules ("users") to share the GPIOTE interrupt,
00022  *          each user defining a set of pins able to generate events to the user.
00023  *          When a GPIOTE interrupt occurs, the GPIOTE interrupt handler will call the event handler
00024  *          of each user for which at least one of the pins generated an event.
00025  *
00026  *          The GPIOTE users are responsible for configuring all their corresponding pins, except
00027  *          the SENSE field, which should be initialized to GPIO_PIN_CNF_SENSE_Disabled.
00028  *          The SENSE field will be updated by the GPIOTE module when it is enabled or disabled,
00029  *          and also while it is enabled.
00030  *
00031  *          The module specifies on which pins events should be generated if the pin(s) goes
00032  *          from low->high or high->low or both directions.
00033  *
00034  * @note    Even if the application is using the @ref app_scheduler, the GPIOTE event handlers will
00035  *          be called directly from the GPIOTE interrupt handler.
00036  */
00037 
00038 #ifndef APP_GPIOTE_H__
00039 #define APP_GPIOTE_H__
00040 
00041 #include <stdint.h>
00042 #include <stdbool.h>
00043 #include "nordic_global.h"
00044 #include "nrf.h"
00045 #include "app_error.h "
00046 #include "app_util.h "
00047 
00048 #define GPIOTE_USER_NODE_SIZE   20          /**< Size of app_gpiote.gpiote_user_t (only for use inside APP_GPIOTE_BUF_SIZE()). */
00049 #define NO_OF_PINS              32          /**< Number of GPIO pins on the nRF51 chip. */
00050 
00051 /**@brief Compute number of bytes required to hold the GPIOTE data structures.
00052  *
00053  * @param[in]   MAX_USERS   Maximum number of GPIOTE users.
00054  *
00055  * @return      Required buffer size (in bytes).
00056  */
00057 #define APP_GPIOTE_BUF_SIZE(MAX_USERS)  ((MAX_USERS) * GPIOTE_USER_NODE_SIZE)
00058 
00059 typedef uint8_t app_gpiote_user_id_t;
00060 
00061 /**@brief GPIOTE event handler type. */
00062 typedef void (*app_gpiote_event_handler_t)(uint32_t event_pins_low_to_high,
00063                                            uint32_t event_pins_high_to_low);
00064 
00065 /**@brief Macro for initializing the GPIOTE module.
00066  *
00067  * @details It will handle dimensioning and allocation of the memory buffer required by the module,
00068  *          making sure that the buffer is correctly aligned.
00069  *
00070  * @param[in]   MAX_USERS   Maximum number of GPIOTE users.
00071  *
00072  * @note Since this macro allocates a buffer, it must only be called once (it is OK to call it
00073  *       several times as long as it is from the same location, e.g. to do a reinitialization).
00074  */
00075 /*lint -emacro(506, APP_GPIOTE_INIT) */ /* Suppress "Constant value Boolean */
00076 #define APP_GPIOTE_INIT(MAX_USERS)                                                                 \
00077     do                                                                                             \
00078     {                                                                                              \
00079         static uint32_t app_gpiote_buf[CEIL_DIV(APP_GPIOTE_BUF_SIZE(MAX_USERS), sizeof(uint32_t))];\
00080         uint32_t ERR_CODE = app_gpiote_init((MAX_USERS), app_gpiote_buf);                          \
00081         APP_ERROR_CHECK(ERR_CODE);                                                                 \
00082     } while (0)
00083 
00084 /**@brief Function for initializing the GPIOTE module.
00085  *
00086  * @note Normally initialization should be done using the APP_GPIOTE_INIT() macro, as that will
00087  *       allocate the buffer needed by the GPIOTE module (including aligning the buffer correctly).
00088  *
00089  * @param[in]   max_users               Maximum number of GPIOTE users.
00090  * @param[in]   p_buffer                Pointer to memory buffer for internal use in the app_gpiote
00091  *                                      module. The size of the buffer can be computed using the
00092  *                                      APP_GPIOTE_BUF_SIZE() macro. The buffer must be aligned to 
00093  *                                      a 4 byte boundary.
00094  *
00095  * @retval      NRF_SUCCESS             Successful initialization.
00096  * @retval      NRF_ERROR_INVALID_PARAM Invalid parameter (buffer not aligned to a 4 byte
00097  *                                      boundary).
00098  */
00099 uint32_t app_gpiote_init(uint8_t max_users, void * p_buffer);
00100 
00101 /**@brief Function for registering a GPIOTE user.
00102  *
00103  * @param[out]  p_user_id               Id for the new GPIOTE user.
00104  * @param[in]   pins_low_to_high_mask   Mask defining which pins will generate events to this user 
00105  *                                      when state is changed from low->high.
00106  * @param[in]   pins_high_to_low_mask   Mask defining which pins will generate events to this user
00107  *                                      when state is changed from high->low.
00108  * @param[in]   event_handler           Pointer to function to be executed when an event occurs.
00109  *
00110  * @retval      NRF_SUCCESS             Successful initialization.
00111  * @retval      NRF_ERROR_INVALID_PARAM Invalid parameter (buffer not aligned to a 4 byte boundary).
00112  * @retval      NRF_ERROR_INALID_STATE  If @ref app_gpiote_init has not been called on the GPIOTE
00113  *                                      module.
00114  * @retval      NRF_ERROR_NO_MEM        Returned if the application tries to register more users
00115  *                                      than defined when the GPIOTE module was initialized in
00116  *                                      @ref app_gpiote_init.
00117  */
00118 uint32_t app_gpiote_user_register(app_gpiote_user_id_t *     p_user_id,
00119                                   uint32_t                   pins_low_to_high_mask,
00120                                   uint32_t                   pins_high_to_low_mask,
00121                                   app_gpiote_event_handler_t event_handler);
00122 
00123 /**@brief Function for informing the GPIOTE module that the specified user wants to use the GPIOTE module.
00124  *
00125  * @param[in]   user_id                 Id of user to enable.
00126  *
00127  * @retval      NRF_SUCCESS             On success.
00128  * @retval      NRF_ERROR_INVALID_PARAM Invalid user_id provided, No a valid user.
00129  * @retval      NRF_ERROR_INALID_STATE  If @ref app_gpiote_init has not been called on the GPIOTE
00130  *                                      module.
00131  */
00132 uint32_t app_gpiote_user_enable(app_gpiote_user_id_t user_id);
00133 
00134 /**@brief Function for informing the GPIOTE module that the specified user is done using the GPIOTE module.
00135  *
00136  * @param[in]   user_id                   Id of user to enable.
00137  *
00138  * @return      NRF_SUCCESS               On success.
00139  * @retval      NRF_ERROR_INVALID_PARAM   Invalid user_id provided, No a valid user.
00140  * @retval      NRF_ERROR_INALID_STATE    If @ref app_gpiote_init has not been called on the GPIOTE
00141  *                                        module.
00142  */
00143 uint32_t app_gpiote_user_disable(app_gpiote_user_id_t user_id);
00144 
00145 /**@brief Function for getting the state of the pins which are registered for the specified user.
00146  *
00147  * @param[in]   user_id         Id of user to check.
00148  * @param[out]  p_pins          Bit mask corresponding to the pins configured to generate events to
00149  *                              the specified user. All bits corresponding to pins in the state
00150  *                              'high' will have value '1', all others will have value '0'.
00151  *
00152  * @return      NRF_SUCCESS               On success.
00153  * @retval      NRF_ERROR_INVALID_PARAM   Invalid user_id provided, No a valid user.
00154  * @retval      NRF_ERROR_INALID_STATE    If @ref app_gpiote_init has not been called on the GPIOTE
00155  *                                        module.
00156  */
00157 uint32_t app_gpiote_pins_state_get(app_gpiote_user_id_t user_id, uint32_t * p_pins);
00158 
00159 #endif // APP_GPIOTE_H__
00160 
00161 /** @} */