/** * Copyright (c) 2015 - 2017, Nordic Semiconductor ASA * * All rights reserved. * * 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, except as embedded into a Nordic * Semiconductor ASA integrated circuit in a product or a software update for * such product, 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. Neither the name of Nordic Semiconductor ASA nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * 4. This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS 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. * */ #ifndef NRF_DRV_TWIS_H__ #define NRF_DRV_TWIS_H__ #include "sdk_config.h" #include "nrf_drv_common.h" #include "nrf_gpio.h" #include "sdk_errors.h" #include "nrf_twis.h" #include #include "app_util.h" #ifdef __cplusplus extern "C" { #endif /**@file * @addtogroup nrf_twis Two Wire slave interface (TWIS) * @ingroup nrf_drivers * @brief Two Wire slave interface (TWIS) APIs. * * * @defgroup nrf_drv_twis TWIS driver * @{ * @ingroup nrf_twis * @brief TWI slave APIs. */ /** * @brief Event callback function event definitions. */ typedef enum { TWIS_EVT_READ_REQ, ///< Read request detected /**< If there is no buffer prepared, buf_req flag in the even will be set. Call then @ref nrf_drv_twis_tx_prepare to give parameters for buffer. */ TWIS_EVT_READ_DONE, ///< Read request has finished - free any data TWIS_EVT_READ_ERROR, ///< Read request finished with error TWIS_EVT_WRITE_REQ, ///< Write request detected /**< If there is no buffer prepared, buf_req flag in the even will be set. Call then @ref nrf_drv_twis_rx_prepare to give parameters for buffer. */ TWIS_EVT_WRITE_DONE, ///< Write request has finished - process data TWIS_EVT_WRITE_ERROR, ///< Write request finished with error TWIS_EVT_GENERAL_ERROR ///< Error that happens not inside WRITE or READ transaction } nrf_drv_twis_evt_type_t; /** * @brief TWIS driver instance structure * * @note We only need instance number here so we could really use just a number * that would be send to every driver function. * But for compatibility reason this number is inserted into the structure. */ typedef struct { uint8_t instNr; /**< Instance number */ }nrf_drv_twis_t; /** * @brief TWIS driver event structure */ typedef struct { nrf_drv_twis_evt_type_t type; ///< Event type union { bool buf_req; ///< Flag for @ref TWIS_EVT_READ_REQ and @ref TWIS_EVT_WRITE_REQ /**< Information if transmission buffer requires to be prepared */ uint32_t tx_amount; ///< Data for @ref TWIS_EVT_READ_DONE uint32_t rx_amount; ///< Data for @ref TWIS_EVT_WRITE_DONE uint32_t error; ///< Data for @ref TWIS_EVT_GENERAL_ERROR }data; }nrf_drv_twis_evt_t; /** * @brief TWI slave event callback function type. * * @param[in] p_event Event information structure. */ typedef void (*nrf_drv_twis_event_handler_t)(nrf_drv_twis_evt_t const * const p_event); /** * @brief Structure for TWIS configuration */ typedef struct { uint32_t addr[2]; //!< Set addresses that this slave should respond. Set 0 to disable. uint32_t scl; //!< SCL pin number nrf_gpio_pin_pull_t scl_pull; //!< SCL pin pull uint32_t sda; //!< SDA pin number nrf_gpio_pin_pull_t sda_pull; //!< SDA pin pull uint8_t interrupt_priority; //!< The priority of interrupt for the module to set }nrf_drv_twis_config_t; /** * @brief Possible error sources * * This is flag enum - values from this enum can be connected using logical or operator. * @note * We could use directly @ref nrf_twis_error_t. Error type enum is redefined here becouse * of possible future extension (eg. supporting timeouts and synchronous mode). */ typedef enum { NRF_DRV_TWIS_ERROR_OVERFLOW = NRF_TWIS_ERROR_OVERFLOW, /**< RX buffer overflow detected, and prevented */ NRF_DRV_TWIS_ERROR_DATA_NACK = NRF_TWIS_ERROR_DATA_NACK, /**< NACK sent after receiving a data byte */ NRF_DRV_TWIS_ERROR_OVERREAD = NRF_TWIS_ERROR_OVERREAD, /**< TX buffer over-read detected, and prevented */ NRF_DRV_TWIS_ERROR_UNEXPECTED_EVENT = 1 << 8 /**< Unexpected event detected by state machine */ }nrf_drv_twis_error_t; /** * @internal * @brief Internal macro for creating TWIS driver instance * * Second level of indirection in creating the instance. * Do not use this macro directly. * Use @ref NRF_DRV_TWIS_INSTANCE instead. */ #define NRF_DRV_TWIS_INSTANCE_x(id) \ { \ TWIS##id##_INSTANCE_INDEX \ } /** * @brief Macro for creating TWIS driver instance * * @param[in] id Instance index. Use 0 for TWIS0 and 1 for TWIS1 */ #define NRF_DRV_TWIS_INSTANCE(id) NRF_DRV_TWIS_INSTANCE_x(id) #define TWIS0_INSTANCE_INDEX 0 #define TWIS1_INSTANCE_INDEX TWIS0_INSTANCE_INDEX+TWIS0_ENABLED /** * @brief Generate default configuration for TWIS driver instance */ #define NRF_DRV_TWIS_DEFAULT_CONFIG \ { \ .addr = { TWIS_DEFAULT_CONFIG_ADDR0, TWIS_DEFAULT_CONFIG_ADDR1 }, \ .scl = 31, \ .scl_pull = (nrf_gpio_pin_pull_t)TWIS_DEFAULT_CONFIG_SCL_PULL, \ .sda = 31, \ .sda_pull = (nrf_gpio_pin_pull_t)TWIS_DEFAULT_CONFIG_SDA_PULL, \ .interrupt_priority = TWIS_DEFAULT_CONFIG_IRQ_PRIORITY \ } /** * @brief Function for initializing the TWIS driver instance. * * Function initializes and enables TWIS driver. * @attention After driver initialization enable it by @ref nrf_drv_twis_enable * * @param[in] p_instance Pointer to the driver instance structure. * @attention @em p_instance has to be global object. * It would be used by interrupts so make it sure that object * would not be destroyed when function is leaving. * @param[in] p_config Initial configuration. * @param[in] event_handler Event handler provided by the user. * * @retval NRF_SUCCESS If initialization was successful. * @retval NRF_ERROR_INVALID_STATE If the driver is already initialized. * @retval NRF_ERROR_BUSY If some other peripheral with the same * instance ID is already in use. This is * possible only if PERIPHERAL_RESOURCE_SHARING_ENABLED * is set to a value other than zero. */ ret_code_t nrf_drv_twis_init( nrf_drv_twis_t const * const p_instance, nrf_drv_twis_config_t const * p_config, nrf_drv_twis_event_handler_t const event_handler); /** * @brief Function for uninitializing the TWIS driver instance. * * Function initializes the peripheral and resets all registers to default values. * * @param[in] p_instance Pointer to the driver instance structure. * @note * It is safe to call nrf_drv_twis_uninit even before initialization. * Actually @ref nrf_drv_twis_init function calls this function to * make sure that TWIS state is known. * @note * If TWIS driver was in uninitialized state before calling this function, * selected pins would not be reset to default configuration. */ void nrf_drv_twis_uninit(nrf_drv_twis_t const * const p_instance); /** * @brief Enable TWIS instance * * This function enables TWIS instance. * Function defined if there is needs for dynamically enabling and disabling the peripheral. * Use @ref nrf_drv_twis_enable and @ref nrf_drv_twis_disable functions. * They do not change any configuration registers. * * @param p_instance Pointer to the driver instance structure. */ void nrf_drv_twis_enable(nrf_drv_twis_t const * const p_instance); /** * @brief Disable TWIS instance * * Disabling TWIS instance gives possibility to turn off the TWIS while * holding configuration done by @ref nrf_drv_twis_init * * @param p_instance Pointer to the driver instance structure. */ void nrf_drv_twis_disable(nrf_drv_twis_t const * const p_instance); /** * @brief Get and clear last error flags * * Function gets information about errors. * This is also the only possibility to exit from error substate of the internal state machine. * * @param[in] p_instance Pointer to the driver instance structure. * @return Error flags defined in @ref nrf_drv_twis_error_t * @attention * This function clears error state and flags. */ uint32_t nrf_drv_twis_error_get_and_clear(nrf_drv_twis_t const * const p_instance); /** * @brief Prepare data for sending * * This function should be used in response for @ref TWIS_EVT_READ_REQ event. * * @param[in] p_instance Pointer to the driver instance structure. * @param[in] p_buf Transmission buffer * @attention Transmission buffer has to be placed in RAM. * @param size Maximum number of bytes that master may read from buffer given. * * @retval NRF_SUCCESS Preparation finished properly * @retval NRF_ERROR_INVALID_ADDR Given @em p_buf is not placed inside the RAM * @retval NRF_ERROR_INVALID_LENGTH Wrong value in @em size parameter * @retval NRF_ERROR_INVALID_STATE Module not initialized or not enabled */ ret_code_t nrf_drv_twis_tx_prepare( nrf_drv_twis_t const * const p_instance, void const * const p_buf, size_t size); /** * @brief Get number of transmitted bytes * * Function returns number of bytes sent. * This function may be called after @ref TWIS_EVT_READ_DONE or @ref TWIS_EVT_READ_ERROR events. * * @param[in] p_instance Pointer to the driver instance structure. * * @return Number of bytes sent. */ size_t nrf_drv_twis_tx_amount(nrf_drv_twis_t const * const p_instance); /** * @brief Prepare data for receiving * * This function should be used in response for @ref TWIS_EVT_WRITE_REQ event. * * @param[in] p_instance Pointer to the driver instance structure. * @param[in] p_buf Buffer that would be filled with received data * @attention Receiving buffer has to be placed in RAM. * @param size Size of the buffer (maximum amount of data to receive) * * @retval NRF_SUCCESS Preparation finished properly * @retval NRF_ERROR_INVALID_ADDR Given @em p_buf is not placed inside the RAM * @retval NRF_ERROR_INVALID_LENGTH Wrong value in @em size parameter * @retval NRF_ERROR_INVALID_STATE Module not initialized or not enabled */ ret_code_t nrf_drv_twis_rx_prepare( nrf_drv_twis_t const * const p_instance, void * const p_buf, size_t size); /** * @brief Get number of received bytes * * Function returns number of bytes received. * This function may be called after @ref TWIS_EVT_WRITE_DONE or @ref TWIS_EVT_WRITE_ERROR events. * * @param[in] p_instance Pointer to the driver instance structure. * * @return Number of bytes received. */ size_t nrf_drv_twis_rx_amount(nrf_drv_twis_t const * const p_instance); /** * @brief Function checks if driver is busy right now * * Actual driver substate is tested. * If driver is in any other state than IDLE or ERROR this function returns true. * * @param[in] p_instance Pointer to the driver instance structure. * * @retval true Driver is in state other than ERROR or IDLE * @retval false There is no transmission pending. */ bool nrf_drv_twis_is_busy(nrf_drv_twis_t const * const p_instance); /** * @brief Function checks if driver is waiting for tx buffer * * If this function returns true, it means that driver is stalled expecting * of the @ref nrf_drv_twis_tx_prepare function call. * * @param[in] p_instance Pointer to the driver instance structure. * * @retval true Driver waits for @ref nrf_drv_twis_tx_prepare * @retval false Driver is not in the state where it waits for preparing tx buffer. */ bool nrf_drv_twis_is_waiting_tx_buff(nrf_drv_twis_t const * const p_instance); /** * @brief Function checks if driver is waiting for rx buffer * * If this function returns true, it means that driver is staled expecting * of the @ref nrf_drv_twis_rx_prepare function call. * * @param[in] p_instance Pointer to the driver instance structure. * * @retval true Driver waits for @ref nrf_drv_twis_rx_prepare * @retval false Driver is not in the state where it waits for preparing rx buffer. */ bool nrf_drv_twis_is_waiting_rx_buff(nrf_drv_twis_t const * const p_instance); /** * @brief Check if driver is sending data * * If this function returns true, it means that there is ongoing output transmission. * * @param[in] p_instance Pointer to the driver instance structure. * * @retval true There is ongoing output transmission. * @retval false Driver is in other state. */ bool nrf_drv_twis_is_pending_tx(nrf_drv_twis_t const * const p_instance); /** * @brief Check if driver is receiving data * * If this function returns true, it means that there is ongoing input transmission. * * @param[in] p_instance Pointer to the driver instance structure. * * @retval true There is ongoing input transmission. * @retval false Driver is in other state. */ bool nrf_drv_twis_is_pending_rx(nrf_drv_twis_t const * const p_instance); /** @} */ /* End of lib_twis_drv group */ #ifdef __cplusplus } #endif #endif /* NRF_DRV_TWIS_H__ */