1 /* 2 * Copyright (c) 2015 - 2018, Nordic Semiconductor ASA 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, this 9 * list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * 3. Neither the name of the copyright holder nor the names of its 16 * contributors may be used to endorse or promote products derived from this 17 * software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 20 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 23 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef NRFX_TWIM_H__ 33 #define NRFX_TWIM_H__ 34 35 #include <nrfx.h> 36 #include <hal/nrf_twim.h> 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /** 43 * @defgroup nrfx_twim TWIM driver 44 * @{ 45 * @ingroup nrf_twim 46 * @brief TWIM peripheral driver. 47 */ 48 49 /** 50 * @brief Structure for the TWI master driver instance. 51 */ 52 typedef struct 53 { 54 NRF_TWIM_Type * p_twim; ///< Pointer to a structure with TWIM registers. 55 uint8_t drv_inst_idx; ///< Driver instance index. 56 } nrfx_twim_t; 57 58 /** 59 * @brief Macro for creating a TWI master driver instance. 60 */ 61 #define NRFX_TWIM_INSTANCE(id) \ 62 { \ 63 .p_twim = NRFX_CONCAT_2(NRF_TWIM, id), \ 64 .drv_inst_idx = NRFX_CONCAT_3(NRFX_TWIM, id, _INST_IDX), \ 65 } 66 67 enum { 68 #if NRFX_CHECK(NRFX_TWIM0_ENABLED) 69 NRFX_TWIM0_INST_IDX, 70 #endif 71 #if NRFX_CHECK(NRFX_TWIM1_ENABLED) 72 NRFX_TWIM1_INST_IDX, 73 #endif 74 NRFX_TWIM_ENABLED_COUNT 75 }; 76 77 /** 78 * @brief Structure for the TWI master driver instance configuration. 79 */ 80 typedef struct 81 { 82 uint32_t scl; ///< SCL pin number. 83 uint32_t sda; ///< SDA pin number. 84 nrf_twim_frequency_t frequency; ///< TWIM frequency. 85 uint8_t interrupt_priority; ///< Interrupt priority. 86 bool hold_bus_uninit; ///< Hold pull up state on gpio pins after uninit. 87 } nrfx_twim_config_t; 88 89 /** 90 * @brief TWI master driver instance default configuration. 91 */ 92 #define NRFX_TWIM_DEFAULT_CONFIG \ 93 { \ 94 .frequency = (nrf_twim_frequency_t)NRFX_TWIM_DEFAULT_CONFIG_FREQUENCY, \ 95 .scl = 31, \ 96 .sda = 31, \ 97 .interrupt_priority = NRFX_TWIM_DEFAULT_CONFIG_IRQ_PRIORITY, \ 98 .hold_bus_uninit = NRFX_TWIM_DEFAULT_CONFIG_HOLD_BUS_UNINIT, \ 99 } 100 101 #define NRFX_TWIM_FLAG_TX_POSTINC (1UL << 0) /**< TX buffer address incremented after transfer. */ 102 #define NRFX_TWIM_FLAG_RX_POSTINC (1UL << 1) /**< RX buffer address incremented after transfer. */ 103 #define NRFX_TWIM_FLAG_NO_XFER_EVT_HANDLER (1UL << 2) /**< Interrupt after each transfer is suppressed, and the event handler is not called. */ 104 #define NRFX_TWIM_FLAG_HOLD_XFER (1UL << 3) /**< Set up the transfer but do not start it. */ 105 #define NRFX_TWIM_FLAG_REPEATED_XFER (1UL << 4) /**< Flag indicating that the transfer will be executed multiple times. */ 106 #define NRFX_TWIM_FLAG_TX_NO_STOP (1UL << 5) /**< Flag indicating that the TX transfer will not end with a stop condition. */ 107 108 /** 109 * @brief TWI master driver event types. 110 */ 111 typedef enum 112 { 113 NRFX_TWIM_EVT_DONE, ///< Transfer completed event. 114 NRFX_TWIM_EVT_ADDRESS_NACK, ///< Error event: NACK received after sending the address. 115 NRFX_TWIM_EVT_DATA_NACK ///< Error event: NACK received after sending a data byte. 116 } nrfx_twim_evt_type_t; 117 118 /** 119 * @brief TWI master driver transfer types. 120 */ 121 typedef enum 122 { 123 NRFX_TWIM_XFER_TX, ///< TX transfer. 124 NRFX_TWIM_XFER_RX, ///< RX transfer. 125 NRFX_TWIM_XFER_TXRX, ///< TX transfer followed by RX transfer with repeated start. 126 NRFX_TWIM_XFER_TXTX ///< TX transfer followed by TX transfer with repeated start. 127 } nrfx_twim_xfer_type_t; 128 129 /** 130 * @brief Structure for a TWI transfer descriptor. 131 */ 132 typedef struct 133 { 134 nrfx_twim_xfer_type_t type; ///< Type of transfer. 135 uint8_t address; ///< Slave address. 136 size_t primary_length; ///< Number of bytes transferred. 137 size_t secondary_length; ///< Number of bytes transferred. 138 uint8_t * p_primary_buf; ///< Pointer to transferred data. 139 uint8_t * p_secondary_buf; ///< Pointer to transferred data. 140 } nrfx_twim_xfer_desc_t; 141 142 143 /**@brief Macro for setting the TX transfer descriptor. */ 144 #define NRFX_TWIM_XFER_DESC_TX(addr, p_data, length) \ 145 { \ 146 .type = NRFX_TWIM_XFER_TX, \ 147 .address = addr, \ 148 .primary_length = length, \ 149 .p_primary_buf = p_data, \ 150 } 151 152 /**@brief Macro for setting the RX transfer descriptor. */ 153 #define NRFX_TWIM_XFER_DESC_RX(addr, p_data, length) \ 154 { \ 155 .type = NRFX_TWIM_XFER_RX, \ 156 .address = addr, \ 157 .primary_length = length, \ 158 .p_primary_buf = p_data, \ 159 } 160 161 /**@brief Macro for setting the TXRX transfer descriptor. */ 162 #define NRFX_TWIM_XFER_DESC_TXRX(addr, p_tx, tx_len, p_rx, rx_len) \ 163 { \ 164 .type = NRFX_TWIM_XFER_TXRX, \ 165 .address = addr, \ 166 .primary_length = tx_len, \ 167 .secondary_length = rx_len, \ 168 .p_primary_buf = p_tx, \ 169 .p_secondary_buf = p_rx, \ 170 } 171 172 /**@brief Macro for setting the TXTX transfer descriptor. */ 173 #define NRFX_TWIM_XFER_DESC_TXTX(addr, p_tx, tx_len, p_tx2, tx_len2) \ 174 { \ 175 .type = NRFX_TWIM_XFER_TXTX, \ 176 .address = addr, \ 177 .primary_length = tx_len, \ 178 .secondary_length = tx_len2, \ 179 .p_primary_buf = p_tx, \ 180 .p_secondary_buf = p_tx2, \ 181 } 182 183 /** 184 * @brief Structure for a TWI event. 185 */ 186 typedef struct 187 { 188 nrfx_twim_evt_type_t type; ///< Event type. 189 nrfx_twim_xfer_desc_t xfer_desc; ///< Transfer details. 190 } nrfx_twim_evt_t; 191 192 /** 193 * @brief TWI event handler prototype. 194 */ 195 typedef void (* nrfx_twim_evt_handler_t)(nrfx_twim_evt_t const * p_event, 196 void * p_context); 197 198 /** 199 * @brief Function for initializing the TWI driver instance. 200 * 201 * @param[in] p_instance Pointer to the driver instance structure. 202 * @param[in] p_config Pointer to the structure with initial configuration. 203 * @param[in] event_handler Event handler provided by the user. If NULL, blocking mode is enabled. 204 * @param[in] p_context Context passed to event handler. 205 * 206 * @retval NRFX_SUCCESS If initialization was successful. 207 * @retval NRFX_ERROR_INVALID_STATE If the driver is in invalid state. 208 * @retval NRFX_ERROR_BUSY If some other peripheral with the same 209 * instance ID is already in use. This is 210 * possible only if @ref nrfx_prs module 211 * is enabled. 212 */ 213 nrfx_err_t nrfx_twim_init(nrfx_twim_t const * p_instance, 214 nrfx_twim_config_t const * p_config, 215 nrfx_twim_evt_handler_t event_handler, 216 void * p_context); 217 218 /** 219 * @brief Function for uninitializing the TWI instance. 220 * 221 * @param[in] p_instance Pointer to the driver instance structure. 222 */ 223 void nrfx_twim_uninit(nrfx_twim_t const * p_instance); 224 225 /** 226 * @brief Function for enabling the TWI instance. 227 * 228 * @param[in] p_instance Pointer to the driver instance structure. 229 */ 230 void nrfx_twim_enable(nrfx_twim_t const * p_instance); 231 232 /** 233 * @brief Function for disabling the TWI instance. 234 * 235 * @param[in] p_instance Pointer to the driver instance structure. 236 */ 237 void nrfx_twim_disable(nrfx_twim_t const * p_instance); 238 239 /** 240 * @brief Function for sending data to a TWI slave. 241 * 242 * The transmission will be stopped when an error occurs. If a transfer is ongoing, 243 * the function returns the error code @ref NRFX_ERROR_BUSY. 244 * 245 * @note Peripherals using EasyDMA (including TWIM) require the transfer buffers 246 * to be placed in the Data RAM region. If this condition is not met, 247 * this function will fail with the error code NRFX_ERROR_INVALID_ADDR. 248 * 249 * @param[in] p_instance Pointer to the driver instance structure. 250 * @param[in] address Address of a specific slave device (only 7 LSB). 251 * @param[in] p_data Pointer to a transmit buffer. 252 * @param[in] length Number of bytes to send. Maximum possible length is 253 * dependent on the used SoC (see the MAXCNT register 254 * description in the Product Specification). The driver 255 * checks it with assertion. 256 * @param[in] no_stop If set, the stop condition is not generated on the bus 257 * after the transfer has completed successfully (allowing 258 * for a repeated start in the next transfer). 259 * 260 * @retval NRFX_SUCCESS If the procedure was successful. 261 * @retval NRFX_ERROR_BUSY If the driver is not ready for a new transfer. 262 * @retval NRFX_ERROR_INTERNAL If an error was detected by hardware. 263 * @retval NRFX_ERROR_INVALID_ADDR If the provided buffer is not placed in the Data RAM region. 264 * @retval NRFX_ERROR_DRV_TWI_ERR_ANACK If NACK received after sending the address in polling mode. 265 * @retval NRFX_ERROR_DRV_TWI_ERR_DNACK If NACK received after sending a data byte in polling mode. 266 */ 267 nrfx_err_t nrfx_twim_tx(nrfx_twim_t const * p_instance, 268 uint8_t address, 269 uint8_t const * p_data, 270 size_t length, 271 bool no_stop); 272 273 /** 274 * @brief Function for reading data from a TWI slave. 275 * 276 * The transmission will be stopped when an error occurs. If a transfer is ongoing, 277 * the function returns the error code @ref NRFX_ERROR_BUSY. 278 * 279 * @param[in] p_instance Pointer to the driver instance structure. 280 * @param[in] address Address of a specific slave device (only 7 LSB). 281 * @param[in] p_data Pointer to a receive buffer. 282 * @param[in] length Number of bytes to be received. Maximum possible length 283 * is dependent on the used SoC (see the MAXCNT register 284 * description in the Product Specification). The driver 285 * checks it with assertion. 286 * 287 * @retval NRFX_SUCCESS If the procedure was successful. 288 * @retval NRFX_ERROR_BUSY If the driver is not ready for a new transfer. 289 * @retval NRFX_ERROR_INTERNAL If an error was detected by hardware. 290 * @retval NRFX_ERROR_DRV_TWI_ERR_ANACK If NACK received after sending the address in polling mode. 291 * @retval NRFX_ERROR_DRV_TWI_ERR_DNACK If NACK received after sending a data byte in polling mode. 292 */ 293 nrfx_err_t nrfx_twim_rx(nrfx_twim_t const * p_instance, 294 uint8_t address, 295 uint8_t * p_data, 296 size_t length); 297 298 /** 299 * @brief Function for preparing a TWI transfer. 300 * 301 * The following transfer types can be configured (@ref nrfx_twim_xfer_desc_t::type): 302 * - @ref NRFX_TWIM_XFER_TXRX<span></span>: Write operation followed by a read operation (without STOP condition in between). 303 * - @ref NRFX_TWIM_XFER_TXTX<span></span>: Write operation followed by a write operation (without STOP condition in between). 304 * - @ref NRFX_TWIM_XFER_TX<span></span>: Write operation (with or without STOP condition). 305 * - @ref NRFX_TWIM_XFER_RX<span></span>: Read operation (with STOP condition). 306 * 307 * @note TXRX and TXTX transfers are supported only in non-blocking mode. 308 * 309 * Additional options are provided using the flags parameter: 310 * - @ref NRFX_TWIM_FLAG_TX_POSTINC and @ref NRFX_TWIM_FLAG_RX_POSTINC<span></span>: Post-incrementation of buffer addresses. Supported only by TWIM. 311 * - @ref NRFX_TWIM_FLAG_NO_XFER_EVT_HANDLER<span></span>: No user event handler after transfer completion. In most cases, this also means no interrupt at the end of the transfer. 312 * - @ref NRFX_TWIM_FLAG_HOLD_XFER<span></span>: Driver is not starting the transfer. Use this flag if the transfer is triggered externally by PPI. Supported only by TWIM. 313 * Use @ref nrfx_twim_start_task_get to get the address of the start task. 314 * - @ref NRFX_TWIM_FLAG_REPEATED_XFER<span></span>: Prepare for repeated transfers. You can set up a number of transfers that will be triggered externally (for example by PPI). 315 * An example is a TXRX transfer with the options @ref NRFX_TWIM_FLAG_RX_POSTINC, @ref NRFX_TWIM_FLAG_NO_XFER_EVT_HANDLER, and @ref NRFX_TWIM_FLAG_REPEATED_XFER. 316 * After the transfer is set up, a set of transfers can be triggered by PPI that will read, for example, the same register of an 317 * external component and put it into a RAM buffer without any interrupts. @ref nrfx_twim_stopped_event_get can be used to get the 318 * address of the STOPPED event, which can be used to count the number of transfers. If @ref NRFX_TWIM_FLAG_REPEATED_XFER is used, 319 * the driver does not set the driver instance into busy state, so you must ensure that the next transfers are set up 320 * when TWIM is not active. Supported only by TWIM. 321 * - @ref NRFX_TWIM_FLAG_TX_NO_STOP<span></span>: No stop condition after TX transfer. 322 * 323 * @note 324 * Some flag combinations are invalid: 325 * - @ref NRFX_TWIM_FLAG_TX_NO_STOP with @ref nrfx_twim_xfer_desc_t::type different than @ref NRFX_TWIM_XFER_TX 326 * - @ref NRFX_TWIM_FLAG_REPEATED_XFER with @ref nrfx_twim_xfer_desc_t::type set to @ref NRFX_TWIM_XFER_TXTX 327 * 328 * If @ref nrfx_twim_xfer_desc_t::type is set to @ref NRFX_TWIM_XFER_TX and the @ref NRFX_TWIM_FLAG_TX_NO_STOP and @ref NRFX_TWIM_FLAG_REPEATED_XFER 329 * flags are set, two tasks must be used to trigger a transfer: TASKS_RESUME followed by TASKS_STARTTX. If no stop condition is generated, 330 * TWIM is in SUSPENDED state. Therefore, it must be resumed before the transfer can be started. 331 * 332 * @note Peripherals using EasyDMA (including TWIM) require the transfer buffers 333 * to be placed in the Data RAM region. If this condition is not met, 334 * this function will fail with the error code NRFX_ERROR_INVALID_ADDR. 335 * 336 * @param[in] p_instance Pointer to the driver instance structure. 337 * @param[in] p_xfer_desc Pointer to the transfer descriptor. 338 * @param[in] flags Transfer options (0 for default settings). 339 * 340 * @retval NRFX_SUCCESS If the procedure was successful. 341 * @retval NRFX_ERROR_BUSY If the driver is not ready for a new transfer. 342 * @retval NRFX_ERROR_NOT_SUPPORTED If the provided parameters are not supported. 343 * @retval NRFX_ERROR_INTERNAL If an error was detected by hardware. 344 * @retval NRFX_ERROR_INVALID_ADDR If the provided buffers are not placed in the Data RAM region. 345 * @retval NRFX_ERROR_DRV_TWI_ERR_ANACK If NACK received after sending the address. 346 * @retval NRFX_ERROR_DRV_TWI_ERR_DNACK If NACK received after sending a data byte. 347 */ 348 nrfx_err_t nrfx_twim_xfer(nrfx_twim_t const * p_instance, 349 nrfx_twim_xfer_desc_t const * p_xfer_desc, 350 uint32_t flags); 351 352 /** 353 * @brief Function for checking the TWI driver state. 354 * 355 * @param[in] p_instance TWI instance. 356 * 357 * @retval true If the TWI driver is currently busy performing a transfer. 358 * @retval false If the TWI driver is ready for a new transfer. 359 */ 360 bool nrfx_twim_is_busy(nrfx_twim_t const * p_instance); 361 362 363 /** 364 * @brief Function for returning the address of a TWIM start task. 365 * 366 * This function should be used if @ref nrfx_twim_xfer was called with the flag @ref NRFX_TWIM_FLAG_HOLD_XFER. 367 * In that case, the transfer is not started by the driver, but it must be started externally by PPI. 368 * 369 * @param[in] p_instance Pointer to the driver instance structure. 370 * @param[in] xfer_type Transfer type used in the last call of the @ref nrfx_twim_xfer function. 371 * 372 * @return Start task address (TX or RX) depending on the value of xfer_type. 373 */ 374 uint32_t nrfx_twim_start_task_get(nrfx_twim_t const * p_instance, nrfx_twim_xfer_type_t xfer_type); 375 376 /** 377 * @brief Function for returning the address of a STOPPED TWIM event. 378 * 379 * A STOPPED event can be used to detect the end of a transfer if the @ref NRFX_TWIM_FLAG_NO_XFER_EVT_HANDLER 380 * option is used. 381 * 382 * @param[in] p_instance Pointer to the driver instance structure. 383 * 384 * @return STOPPED event address. 385 */ 386 uint32_t nrfx_twim_stopped_event_get(nrfx_twim_t const * p_instance); 387 388 389 void nrfx_twim_0_irq_handler(void); 390 void nrfx_twim_1_irq_handler(void); 391 392 393 /** @} */ 394 395 #ifdef __cplusplus 396 } 397 #endif 398 399 #endif // NRFX_TWIM_H__ 400