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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 NRFX_TWIS_H__ #define NRFX_TWIS_H__ #include #include #include #ifdef __cplusplus extern "C" { #endif /** * @defgroup nrfx_twis TWIS driver * @{ * @ingroup nrf_twis * @brief Two Wire Slave interface (TWIS) peripheral driver. */ /** * @brief TWIS driver instance data structure. */ typedef struct { NRF_TWIS_Type * p_reg; ///< Pointer to a structure with TWIS registers. uint8_t drv_inst_idx; ///< Driver instance index. } nrfx_twis_t; enum { #if NRFX_CHECK(NRFX_TWIS0_ENABLED) NRFX_TWIS0_INST_IDX, #endif #if NRFX_CHECK(NRFX_TWIS1_ENABLED) NRFX_TWIS1_INST_IDX, #endif NRFX_TWIS_ENABLED_COUNT }; /** * @brief Macro for creating a TWIS driver instance. */ #define NRFX_TWIS_INSTANCE(id) \ { \ .p_reg = NRFX_CONCAT_2(NRF_TWIS, id), \ .drv_inst_idx = NRFX_CONCAT_3(NRFX_TWIS, id, _INST_IDX), \ } /** * @brief Event callback function event definitions. */ typedef enum { NRFX_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 nrfx_twis_tx_prepare to give parameters for buffer. */ NRFX_TWIS_EVT_READ_DONE, ///< Read request has finished - free any data. NRFX_TWIS_EVT_READ_ERROR, ///< Read request finished with error. NRFX_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 nrfx_twis_rx_prepare to give parameters for buffer. */ NRFX_TWIS_EVT_WRITE_DONE, ///< Write request has finished - process data. NRFX_TWIS_EVT_WRITE_ERROR, ///< Write request finished with error. NRFX_TWIS_EVT_GENERAL_ERROR ///< Error that happens not inside WRITE or READ transaction. } nrfx_twis_evt_type_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 because * of possible future extension (eg. supporting timeouts and synchronous mode). */ typedef enum { NRFX_TWIS_ERROR_OVERFLOW = NRF_TWIS_ERROR_OVERFLOW, /**< RX buffer overflow detected, and prevented. */ NRFX_TWIS_ERROR_DATA_NACK = NRF_TWIS_ERROR_DATA_NACK, /**< NACK sent after receiving a data byte. */ NRFX_TWIS_ERROR_OVERREAD = NRF_TWIS_ERROR_OVERREAD, /**< TX buffer over-read detected, and prevented. */ NRFX_TWIS_ERROR_UNEXPECTED_EVENT = 1 << 8 /**< Unexpected event detected by state machine. */ } nrfx_twis_error_t; /** * @brief TWIS driver event structure. */ typedef struct { nrfx_twis_evt_type_t type; ///< Event type. union { bool buf_req; ///< Flag for @ref NRFX_TWIS_EVT_READ_REQ and @ref NRFX_TWIS_EVT_WRITE_REQ. /**< Information if transmission buffer requires to be prepared. */ uint32_t tx_amount; ///< Data for @ref NRFX_TWIS_EVT_READ_DONE. uint32_t rx_amount; ///< Data for @ref NRFX_TWIS_EVT_WRITE_DONE. uint32_t error; ///< Data for @ref NRFX_TWIS_EVT_GENERAL_ERROR. } data; } nrfx_twis_evt_t; /** * @brief TWI slave event callback function type. * * @param[in] p_event Event information structure. */ typedef void (*nrfx_twis_event_handler_t)(nrfx_twis_evt_t 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. uint32_t sda; //!< SDA pin number. nrf_gpio_pin_pull_t scl_pull; //!< SCL pin pull. nrf_gpio_pin_pull_t sda_pull; //!< SDA pin pull. uint8_t interrupt_priority; //!< The priority of interrupt for the module to set. } nrfx_twis_config_t; /** * @brief Generate default configuration for TWIS driver instance. */ #define NRFX_TWIS_DEFAULT_CONFIG \ { \ .addr = { NRFX_TWIS_DEFAULT_CONFIG_ADDR0, \ NRFX_TWIS_DEFAULT_CONFIG_ADDR1 }, \ .scl = 31, \ .scl_pull = (nrf_gpio_pin_pull_t)NRFX_TWIS_DEFAULT_CONFIG_SCL_PULL, \ .sda = 31, \ .sda_pull = (nrf_gpio_pin_pull_t)NRFX_TWIS_DEFAULT_CONFIG_SDA_PULL, \ .interrupt_priority = NRFX_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 nrfx_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 Pointer to the structure with initial configuration. * @param[in] event_handler Event handler provided by the user. * * @retval NRFX_SUCCESS If initialization was successful. * @retval NRFX_ERROR_INVALID_STATE If the driver is already initialized. * @retval NRFX_ERROR_BUSY If some other peripheral with the same * instance ID is already in use. This is * possible only if NRFX_PRS_ENABLED * is set to a value other than zero. */ nrfx_err_t nrfx_twis_init(nrfx_twis_t const * p_instance, nrfx_twis_config_t const * p_config, nrfx_twis_event_handler_t 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 nrfx_twis_uninit even before initialization. * Actually @ref nrfx_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 nrfx_twis_uninit(nrfx_twis_t 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 nrfx_twis_enable and @ref nrfx_twis_disable functions. * They do not change any configuration registers. * * @param p_instance Pointer to the driver instance structure. */ void nrfx_twis_enable(nrfx_twis_t const * p_instance); /** * @brief Disable TWIS instance. * * Disabling TWIS instance gives possibility to turn off the TWIS while * holding configuration done by @ref nrfx_twis_init. * * @param p_instance Pointer to the driver instance structure. */ void nrfx_twis_disable(nrfx_twis_t 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 nrfx_twis_error_t. * @attention * This function clears error state and flags. */ uint32_t nrfx_twis_error_get_and_clear(nrfx_twis_t const * p_instance); /** * @brief Prepare data for sending. * * This function should be used in response for @ref NRFX_TWIS_EVT_READ_REQ event. * * @note Peripherals using EasyDMA (including TWIS) require the transfer buffers * to be placed in the Data RAM region. If this condition is not met, * this function will fail with the error code NRFX_ERROR_INVALID_ADDR. * * @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 NRFX_SUCCESS Preparation finished properly. * @retval NRFX_ERROR_INVALID_ADDR Given @em p_buf is not placed inside the RAM. * @retval NRFX_ERROR_INVALID_LENGTH Wrong value in @em size parameter. * @retval NRFX_ERROR_INVALID_STATE Module not initialized or not enabled. */ nrfx_err_t nrfx_twis_tx_prepare(nrfx_twis_t const * p_instance, void 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 NRFX_TWIS_EVT_READ_DONE or @ref NRFX_TWIS_EVT_READ_ERROR events. * * @param[in] p_instance Pointer to the driver instance structure. * * @return Number of bytes sent. */ __STATIC_INLINE size_t nrfx_twis_tx_amount(nrfx_twis_t const * p_instance); /** * @brief Prepare data for receiving * * This function should be used in response for @ref NRFX_TWIS_EVT_WRITE_REQ event. * * @note Peripherals using EasyDMA (including TWIS) require the transfer buffers * to be placed in the Data RAM region. If this condition is not met, * this function will fail with the error code NRFX_ERROR_INVALID_ADDR. * * @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 NRFX_SUCCESS Preparation finished properly. * @retval NRFX_ERROR_INVALID_ADDR Given @em p_buf is not placed inside the RAM. * @retval NRFX_ERROR_INVALID_LENGTH Wrong value in @em size parameter. * @retval NRFX_ERROR_INVALID_STATE Module not initialized or not enabled. */ nrfx_err_t nrfx_twis_rx_prepare(nrfx_twis_t const * p_instance, void * p_buf, size_t size); /** * @brief Get number of received bytes. * * Function returns number of bytes received. * This function may be called after @ref NRFX_TWIS_EVT_WRITE_DONE or @ref NRFX_TWIS_EVT_WRITE_ERROR events. * * @param[in] p_instance Pointer to the driver instance structure. * * @return Number of bytes received. */ __STATIC_INLINE size_t nrfx_twis_rx_amount(nrfx_twis_t 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 nrfx_twis_is_busy(nrfx_twis_t 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 nrfx_twis_tx_prepare function call. * * @param[in] p_instance Pointer to the driver instance structure. * * @retval true Driver waits for @ref nrfx_twis_tx_prepare. * @retval false Driver is not in the state where it waits for preparing tx buffer. */ bool nrfx_twis_is_waiting_tx_buff(nrfx_twis_t 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 nrfx_twis_rx_prepare function call. * * @param[in] p_instance Pointer to the driver instance structure. * * @retval true Driver waits for @ref nrfx_twis_rx_prepare. * @retval false Driver is not in the state where it waits for preparing rx buffer. */ bool nrfx_twis_is_waiting_rx_buff(nrfx_twis_t 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 nrfx_twis_is_pending_tx(nrfx_twis_t 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 nrfx_twis_is_pending_rx(nrfx_twis_t const * p_instance); #ifndef SUPPRESS_INLINE_IMPLEMENTATION __STATIC_INLINE size_t nrfx_twis_tx_amount(nrfx_twis_t const * p_instance) { return nrf_twis_tx_amount_get(p_instance->p_reg); } __STATIC_INLINE size_t nrfx_twis_rx_amount(nrfx_twis_t const * p_instance) { return nrf_twis_rx_amount_get(p_instance->p_reg); } #endif // SUPPRESS_INLINE_IMPLEMENTATION void nrfx_twis_0_irq_handler(void); void nrfx_twis_1_irq_handler(void); /** @} */ #ifdef __cplusplus } #endif #endif // NRFX_TWIS_H__