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  * @warning If multiple users registers for the same pins the behavior for those pins are undefined.
00038  */
00039 
00040 #ifndef APP_GPIOTE_H__
00041 #define APP_GPIOTE_H__
00042 
00043 #include <stdint.h>
00044 #include <stdbool.h>
00045 #include "nrf.h"
00046 #include "app_error.h "
00047 #include "app_util.h "
00048 
00049 #define GPIOTE_USER_NODE_SIZE   20          /**< Size of app_gpiote.gpiote_user_t (only for use inside APP_GPIOTE_BUF_SIZE()). */
00050 #define NO_OF_PINS              32          /**< Number of GPIO pins on the nRF51 chip. */
00051 
00052 /**@brief Compute number of bytes required to hold the GPIOTE data structures.
00053  *
00054  * @param[in]   MAX_USERS   Maximum number of GPIOTE users.
00055  *
00056  * @return      Required buffer size (in bytes).
00057  */
00058 #define APP_GPIOTE_BUF_SIZE(MAX_USERS)  ((MAX_USERS) * GPIOTE_USER_NODE_SIZE)
00059 
00060 typedef uint8_t app_gpiote_user_id_t;
00061 
00062 /**@brief GPIOTE event handler type. */
00063 typedef void (*app_gpiote_event_handler_t)(uint32_t event_pins_low_to_high,
00064                                            uint32_t event_pins_high_to_low);
00065 
00066 /**@brief GPIOTE input event handler type. */
00067 typedef void (*app_gpiote_input_event_handler_t)(void);
00068 
00069 /**@brief Macro for initializing the GPIOTE module.
00070  *
00071  * @details It will handle dimensioning and allocation of the memory buffer required by the module,
00072  *          making sure that the buffer is correctly aligned.
00073  *
00074  * @param[in]   MAX_USERS   Maximum number of GPIOTE users.
00075  *
00076  * @note Since this macro allocates a buffer, it must only be called once (it is OK to call it
00077  *       several times as long as it is from the same location, e.g. to do a reinitialization).
00078  */
00079 /*lint -emacro(506, APP_GPIOTE_INIT) */ /* Suppress "Constant value Boolean */
00080 #define APP_GPIOTE_INIT(MAX_USERS)                                                                 \
00081     do                                                                                             \
00082     {                                                                                              \
00083         static uint32_t app_gpiote_buf[CEIL_DIV(APP_GPIOTE_BUF_SIZE(MAX_USERS), sizeof(uint32_t))];\
00084         uint32_t ERR_CODE = app_gpiote_init((MAX_USERS), app_gpiote_buf);                          \
00085         APP_ERROR_CHECK(ERR_CODE);                                                                 \
00086     } while (0)
00087 
00088 /**@brief Function for initializing the GPIOTE module.
00089  *
00090  * @note Normally initialization should be done using the APP_GPIOTE_INIT() macro, as that will
00091  *       allocate the buffer needed by the GPIOTE module (including aligning the buffer correctly).
00092  *
00093  * @param[in]   max_users               Maximum number of GPIOTE users.
00094  * @param[in]   p_buffer                Pointer to memory buffer for internal use in the app_gpiote
00095  *                                      module. The size of the buffer can be computed using the
00096  *                                      APP_GPIOTE_BUF_SIZE() macro. The buffer must be aligned to 
00097  *                                      a 4 byte boundary.
00098  *
00099  * @retval      NRF_SUCCESS             Successful initialization.
00100  * @retval      NRF_ERROR_INVALID_PARAM Invalid parameter (buffer not aligned to a 4 byte
00101  *                                      boundary).
00102  */
00103 uint32_t app_gpiote_init(uint8_t max_users, void * p_buffer);
00104 
00105 /**@brief Function for registering a GPIOTE user.
00106  *
00107  * @param[out]  p_user_id               Id for the new GPIOTE user.
00108  * @param[in]   pins_low_to_high_mask   Mask defining which pins will generate events to this user 
00109  *                                      when state is changed from low->high.
00110  * @param[in]   pins_high_to_low_mask   Mask defining which pins will generate events to this user
00111  *                                      when state is changed from high->low.
00112  * @param[in]   event_handler           Pointer to function to be executed when an event occurs.
00113  *
00114  * @retval      NRF_SUCCESS             Successful initialization.
00115  * @retval      NRF_ERROR_INVALID_PARAM Invalid parameter (buffer not aligned to a 4 byte boundary).
00116  * @retval      NRF_ERROR_INALID_STATE  If @ref app_gpiote_init has not been called on the GPIOTE
00117  *                                      module.
00118  * @retval      NRF_ERROR_NO_MEM        Returned if the application tries to register more users
00119  *                                      than defined when the GPIOTE module was initialized in
00120  *                                      @ref app_gpiote_init.
00121  */
00122 uint32_t app_gpiote_user_register(app_gpiote_user_id_t *     p_user_id,
00123                                   uint32_t                   pins_low_to_high_mask,
00124                                   uint32_t                   pins_high_to_low_mask,
00125                                   app_gpiote_event_handler_t event_handler);
00126 
00127 /**@brief Function for informing the GPIOTE module that the specified user wants to use the GPIOTE module.
00128  *
00129  * @param[in]   user_id                 Id of user to enable.
00130  *
00131  * @retval      NRF_SUCCESS             On success.
00132  * @retval      NRF_ERROR_INVALID_PARAM Invalid user_id provided, No a valid user.
00133  * @retval      NRF_ERROR_INALID_STATE  If @ref app_gpiote_init has not been called on the GPIOTE
00134  *                                      module.
00135  */
00136 uint32_t app_gpiote_user_enable(app_gpiote_user_id_t user_id);
00137 
00138 /**@brief Function for informing the GPIOTE module that the specified user is done using the GPIOTE module.
00139  *
00140  * @param[in]   user_id                   Id of user to enable.
00141  *
00142  * @return      NRF_SUCCESS               On success.
00143  * @retval      NRF_ERROR_INVALID_PARAM   Invalid user_id provided, No a valid user.
00144  * @retval      NRF_ERROR_INALID_STATE    If @ref app_gpiote_init has not been called on the GPIOTE
00145  *                                        module.
00146  */
00147 uint32_t app_gpiote_user_disable(app_gpiote_user_id_t user_id);
00148 
00149 /**@brief Function for getting the state of the pins which are registered for the specified user.
00150  *
00151  * @param[in]   user_id         Id of user to check.
00152  * @param[out]  p_pins          Bit mask corresponding to the pins configured to generate events to
00153  *                              the specified user. All bits corresponding to pins in the state
00154  *                              'high' will have value '1', all others will have value '0'.
00155  *
00156  * @return      NRF_SUCCESS               On success.
00157  * @retval      NRF_ERROR_INVALID_PARAM   Invalid user_id provided, No a valid user.
00158  * @retval      NRF_ERROR_INALID_STATE    If @ref app_gpiote_init has not been called on the GPIOTE
00159  *                                        module.
00160  */
00161 uint32_t app_gpiote_pins_state_get(app_gpiote_user_id_t user_id, uint32_t * p_pins);
00162 
00163 /**@brief Function for registering event handlers for GPIOTE IN events.
00164  *
00165  * @param[in] channel         GPIOTE channel [0..3].
00166  * @param[in] pin             Pins associated with GPIOTE channel. Changes on following pins will generate events.
00167  * @param[in] polarity        Specify operation on input that shall trigger IN event.
00168  * @param[in] event_handler   Event handler invoked on the IN event in the GPIOTE interrupt.
00169  *
00170  * @return   NRF_SUCCESS                 On success.
00171  * @retval   NRF_ERROR_INVALID_PARAM     Invalid channel or pin number.
00172  * @retval   NRF_ERROR_NOT_SUPPORTED     Driver doesn't support IN events.
00173  */
00174 uint32_t app_gpiote_input_event_handler_register(const uint8_t channel,
00175                                                  const uint32_t pin,
00176                                                  const uint32_t polarity,
00177                                                  app_gpiote_input_event_handler_t event_handler);
00178 
00179 /**@brief Function for unregistering event handlers for GPIOTE IN events.
00180  *
00181  * @return   NRF_SUCCESS                 On success.
00182  * @retval   NRF_ERROR_NOT_SUPPORTED     Driver doesn't support IN events.
00183  */
00184 uint32_t app_gpiote_input_event_handler_unregister(const uint8_t channel);
00185 
00186 /**@brief Function for registering event handler invoked at the end of a GPIOTE interrupt.
00187  *
00188  * @param[in] event_handler    Event handler invoked at the end of the GPIOTE interrupt.
00189  *
00190  * @return   NRF_SUCCESS                 On success.
00191  * @retval   NRF_ERROR_NOT_SUPPORTED     Driver doesn't support IN events.
00192  */
00193 uint32_t app_gpiote_end_irq_event_handler_register(app_gpiote_input_event_handler_t event_handler);
00194 
00195 /**@brief Function for unregistering event handler invoked at the end of a GPIOTE interrupt.
00196  *
00197  * @return   NRF_SUCCESS                 On success.
00198  * @retval   NRF_ERROR_NOT_SUPPORTED     Driver doesn't support IN events.
00199  */
00200 uint32_t app_gpiote_end_irq_event_handler_unregister(void);
00201 
00202 /**@brief Function for enabling interrupts in the GPIOTE driver.
00203  *
00204  * @return   NRF_SUCCESS                 On success.
00205  * @retval   NRF_ERROR_NOT_SUPPORTED     Driver doesn't support.
00206  */
00207 uint32_t app_gpiote_enable_interrupts(void);
00208 
00209 /**@brief Function for disabling interrupts in the GPIOTE driver.
00210  *
00211  * @return   NRF_SUCCESS                 On success.
00212  * @retval   NRF_ERROR_NOT_SUPPORTED     Driver doesn't support.
00213  */
00214 uint32_t app_gpiote_disable_interrupts(void);
00215 
00216 
00217 #endif // APP_GPIOTE_H__
00218 
00219 /** @} */