1 /* 2 * SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #pragma once 8 9 #ifdef __cplusplus 10 extern "C" { 11 #endif 12 13 #include "soc/soc_caps.h" 14 #if SOC_TWAI_SUPPORTED 15 16 #include "freertos/FreeRTOS.h" 17 #include "esp_types.h" 18 #include "esp_intr_alloc.h" 19 #include "esp_err.h" 20 #include "gpio.h" 21 #include "hal/twai_types.h" 22 23 /* -------------------- Default initializers and flags ---------------------- */ 24 /** @cond */ //Doxy command to hide preprocessor definitions from docs 25 /** 26 * @brief Initializer macro for general configuration structure. 27 * 28 * This initializer macros allows the TX GPIO, RX GPIO, and operating mode to be 29 * configured. The other members of the general configuration structure are 30 * assigned default values. 31 */ 32 #define TWAI_GENERAL_CONFIG_DEFAULT(tx_io_num, rx_io_num, op_mode) {.mode = op_mode, .tx_io = tx_io_num, .rx_io = rx_io_num, \ 33 .clkout_io = TWAI_IO_UNUSED, .bus_off_io = TWAI_IO_UNUSED, \ 34 .tx_queue_len = 5, .rx_queue_len = 5, \ 35 .alerts_enabled = TWAI_ALERT_NONE, .clkout_divider = 0, \ 36 .intr_flags = ESP_INTR_FLAG_LEVEL1} 37 38 /** 39 * @brief Alert flags 40 * 41 * The following flags represents the various kind of alerts available in 42 * the TWAI driver. These flags can be used when configuring/reconfiguring 43 * alerts, or when calling twai_read_alerts(). 44 * 45 * @note The TWAI_ALERT_AND_LOG flag is not an actual alert, but will configure 46 * the TWAI driver to log to UART when an enabled alert occurs. 47 */ 48 #define TWAI_ALERT_TX_IDLE 0x00000001 /**< Alert(1): No more messages to transmit */ 49 #define TWAI_ALERT_TX_SUCCESS 0x00000002 /**< Alert(2): The previous transmission was successful */ 50 #define TWAI_ALERT_RX_DATA 0x00000004 /**< Alert(4): A frame has been received and added to the RX queue */ 51 #define TWAI_ALERT_BELOW_ERR_WARN 0x00000008 /**< Alert(8): Both error counters have dropped below error warning limit */ 52 #define TWAI_ALERT_ERR_ACTIVE 0x00000010 /**< Alert(16): TWAI controller has become error active */ 53 #define TWAI_ALERT_RECOVERY_IN_PROGRESS 0x00000020 /**< Alert(32): TWAI controller is undergoing bus recovery */ 54 #define TWAI_ALERT_BUS_RECOVERED 0x00000040 /**< Alert(64): TWAI controller has successfully completed bus recovery */ 55 #define TWAI_ALERT_ARB_LOST 0x00000080 /**< Alert(128): The previous transmission lost arbitration */ 56 #define TWAI_ALERT_ABOVE_ERR_WARN 0x00000100 /**< Alert(256): One of the error counters have exceeded the error warning limit */ 57 #define TWAI_ALERT_BUS_ERROR 0x00000200 /**< Alert(512): A (Bit, Stuff, CRC, Form, ACK) error has occurred on the bus */ 58 #define TWAI_ALERT_TX_FAILED 0x00000400 /**< Alert(1024): The previous transmission has failed (for single shot transmission) */ 59 #define TWAI_ALERT_RX_QUEUE_FULL 0x00000800 /**< Alert(2048): The RX queue is full causing a frame to be lost */ 60 #define TWAI_ALERT_ERR_PASS 0x00001000 /**< Alert(4096): TWAI controller has become error passive */ 61 #define TWAI_ALERT_BUS_OFF 0x00002000 /**< Alert(8192): Bus-off condition occurred. TWAI controller can no longer influence bus */ 62 #define TWAI_ALERT_RX_FIFO_OVERRUN 0x00004000 /**< Alert(16384): An RX FIFO overrun has occurred */ 63 #define TWAI_ALERT_TX_RETRIED 0x00008000 /**< Alert(32768): An message transmission was cancelled and retried due to an errata workaround */ 64 #define TWAI_ALERT_PERIPH_RESET 0x00010000 /**< Alert(65536): The TWAI controller was reset */ 65 #define TWAI_ALERT_ALL 0x0001FFFF /**< Bit mask to enable all alerts during configuration */ 66 #define TWAI_ALERT_NONE 0x00000000 /**< Bit mask to disable all alerts during configuration */ 67 #define TWAI_ALERT_AND_LOG 0x00020000 /**< Bit mask to enable alerts to also be logged when they occur. Note that logging from the ISR is disabled if CONFIG_TWAI_ISR_IN_IRAM is enabled (see docs). */ 68 69 /** @endcond */ 70 71 #define TWAI_IO_UNUSED ((gpio_num_t) -1) /**< Marks GPIO as unused in TWAI configuration */ 72 73 /* ----------------------- Enum and Struct Definitions ---------------------- */ 74 75 /** 76 * @brief TWAI driver states 77 */ 78 typedef enum { 79 TWAI_STATE_STOPPED, /**< Stopped state. The TWAI controller will not participate in any TWAI bus activities */ 80 TWAI_STATE_RUNNING, /**< Running state. The TWAI controller can transmit and receive messages */ 81 TWAI_STATE_BUS_OFF, /**< Bus-off state. The TWAI controller cannot participate in bus activities until it has recovered */ 82 TWAI_STATE_RECOVERING, /**< Recovering state. The TWAI controller is undergoing bus recovery */ 83 } twai_state_t; 84 85 /** 86 * @brief Structure for general configuration of the TWAI driver 87 * 88 * @note Macro initializers are available for this structure 89 */ 90 typedef struct { 91 twai_mode_t mode; /**< Mode of TWAI controller */ 92 gpio_num_t tx_io; /**< Transmit GPIO number */ 93 gpio_num_t rx_io; /**< Receive GPIO number */ 94 gpio_num_t clkout_io; /**< CLKOUT GPIO number (optional, set to -1 if unused) */ 95 gpio_num_t bus_off_io; /**< Bus off indicator GPIO number (optional, set to -1 if unused) */ 96 uint32_t tx_queue_len; /**< Number of messages TX queue can hold (set to 0 to disable TX Queue) */ 97 uint32_t rx_queue_len; /**< Number of messages RX queue can hold */ 98 uint32_t alerts_enabled; /**< Bit field of alerts to enable (see documentation) */ 99 uint32_t clkout_divider; /**< CLKOUT divider. Can be 1 or any even number from 2 to 14 (optional, set to 0 if unused) */ 100 int intr_flags; /**< Interrupt flags to set the priority of the driver's ISR. Note that to use the ESP_INTR_FLAG_IRAM, the CONFIG_TWAI_ISR_IN_IRAM option should be enabled first. */ 101 } twai_general_config_t; 102 103 /** 104 * @brief Structure to store status information of TWAI driver 105 */ 106 typedef struct { 107 twai_state_t state; /**< Current state of TWAI controller (Stopped/Running/Bus-Off/Recovery) */ 108 uint32_t msgs_to_tx; /**< Number of messages queued for transmission or awaiting transmission completion */ 109 uint32_t msgs_to_rx; /**< Number of messages in RX queue waiting to be read */ 110 uint32_t tx_error_counter; /**< Current value of Transmit Error Counter */ 111 uint32_t rx_error_counter; /**< Current value of Receive Error Counter */ 112 uint32_t tx_failed_count; /**< Number of messages that failed transmissions */ 113 uint32_t rx_missed_count; /**< Number of messages that were lost due to a full RX queue (or errata workaround if enabled) */ 114 uint32_t rx_overrun_count; /**< Number of messages that were lost due to a RX FIFO overrun */ 115 uint32_t arb_lost_count; /**< Number of instances arbitration was lost */ 116 uint32_t bus_error_count; /**< Number of instances a bus error has occurred */ 117 } twai_status_info_t; 118 119 /* ------------------------------ Public API -------------------------------- */ 120 121 /** 122 * @brief Install TWAI driver 123 * 124 * This function installs the TWAI driver using three configuration structures. 125 * The required memory is allocated and the TWAI driver is placed in the stopped 126 * state after running this function. 127 * 128 * @param[in] g_config General configuration structure 129 * @param[in] t_config Timing configuration structure 130 * @param[in] f_config Filter configuration structure 131 * 132 * @note Macro initializers are available for the configuration structures (see documentation) 133 * 134 * @note To reinstall the TWAI driver, call twai_driver_uninstall() first 135 * 136 * @return 137 * - ESP_OK: Successfully installed TWAI driver 138 * - ESP_ERR_INVALID_ARG: Arguments are invalid 139 * - ESP_ERR_NO_MEM: Insufficient memory 140 * - ESP_ERR_INVALID_STATE: Driver is already installed 141 */ 142 esp_err_t twai_driver_install(const twai_general_config_t *g_config, const twai_timing_config_t *t_config, const twai_filter_config_t *f_config); 143 144 /** 145 * @brief Uninstall the TWAI driver 146 * 147 * This function uninstalls the TWAI driver, freeing the memory utilized by the 148 * driver. This function can only be called when the driver is in the stopped 149 * state or the bus-off state. 150 * 151 * @warning The application must ensure that no tasks are blocked on TX/RX 152 * queues or alerts when this function is called. 153 * 154 * @return 155 * - ESP_OK: Successfully uninstalled TWAI driver 156 * - ESP_ERR_INVALID_STATE: Driver is not in stopped/bus-off state, or is not installed 157 */ 158 esp_err_t twai_driver_uninstall(void); 159 160 /** 161 * @brief Start the TWAI driver 162 * 163 * This function starts the TWAI driver, putting the TWAI driver into the running 164 * state. This allows the TWAI driver to participate in TWAI bus activities such 165 * as transmitting/receiving messages. The TX and RX queue are reset in this function, 166 * clearing any messages that are unread or pending transmission. This function 167 * can only be called when the TWAI driver is in the stopped state. 168 * 169 * @return 170 * - ESP_OK: TWAI driver is now running 171 * - ESP_ERR_INVALID_STATE: Driver is not in stopped state, or is not installed 172 */ 173 esp_err_t twai_start(void); 174 175 /** 176 * @brief Stop the TWAI driver 177 * 178 * This function stops the TWAI driver, preventing any further message from being 179 * transmitted or received until twai_start() is called. Any messages in the TX 180 * queue are cleared. Any messages in the RX queue should be read by the 181 * application after this function is called. This function can only be called 182 * when the TWAI driver is in the running state. 183 * 184 * @warning A message currently being transmitted/received on the TWAI bus will 185 * be ceased immediately. This may lead to other TWAI nodes interpreting 186 * the unfinished message as an error. 187 * 188 * @return 189 * - ESP_OK: TWAI driver is now Stopped 190 * - ESP_ERR_INVALID_STATE: Driver is not in running state, or is not installed 191 */ 192 esp_err_t twai_stop(void); 193 194 /** 195 * @brief Transmit a TWAI message 196 * 197 * This function queues a TWAI message for transmission. Transmission will start 198 * immediately if no other messages are queued for transmission. If the TX queue 199 * is full, this function will block until more space becomes available or until 200 * it times out. If the TX queue is disabled (TX queue length = 0 in configuration), 201 * this function will return immediately if another message is undergoing 202 * transmission. This function can only be called when the TWAI driver is in the 203 * running state and cannot be called under Listen Only Mode. 204 * 205 * @param[in] message Message to transmit 206 * @param[in] ticks_to_wait Number of FreeRTOS ticks to block on the TX queue 207 * 208 * @note This function does not guarantee that the transmission is successful. 209 * The TX_SUCCESS/TX_FAILED alert can be enabled to alert the application 210 * upon the success/failure of a transmission. 211 * 212 * @note The TX_IDLE alert can be used to alert the application when no other 213 * messages are awaiting transmission. 214 * 215 * @return 216 * - ESP_OK: Transmission successfully queued/initiated 217 * - ESP_ERR_INVALID_ARG: Arguments are invalid 218 * - ESP_ERR_TIMEOUT: Timed out waiting for space on TX queue 219 * - ESP_FAIL: TX queue is disabled and another message is currently transmitting 220 * - ESP_ERR_INVALID_STATE: TWAI driver is not in running state, or is not installed 221 * - ESP_ERR_NOT_SUPPORTED: Listen Only Mode does not support transmissions 222 */ 223 esp_err_t twai_transmit(const twai_message_t *message, TickType_t ticks_to_wait); 224 225 /** 226 * @brief Receive a TWAI message 227 * 228 * This function receives a message from the RX queue. The flags field of the 229 * message structure will indicate the type of message received. This function 230 * will block if there are no messages in the RX queue 231 * 232 * @param[out] message Received message 233 * @param[in] ticks_to_wait Number of FreeRTOS ticks to block on RX queue 234 * 235 * @warning The flags field of the received message should be checked to determine 236 * if the received message contains any data bytes. 237 * 238 * @return 239 * - ESP_OK: Message successfully received from RX queue 240 * - ESP_ERR_TIMEOUT: Timed out waiting for message 241 * - ESP_ERR_INVALID_ARG: Arguments are invalid 242 * - ESP_ERR_INVALID_STATE: TWAI driver is not installed 243 */ 244 esp_err_t twai_receive(twai_message_t *message, TickType_t ticks_to_wait); 245 246 /** 247 * @brief Read TWAI driver alerts 248 * 249 * This function will read the alerts raised by the TWAI driver. If no alert has 250 * been issued when this function is called, this function will block until an alert 251 * occurs or until it timeouts. 252 * 253 * @param[out] alerts Bit field of raised alerts (see documentation for alert flags) 254 * @param[in] ticks_to_wait Number of FreeRTOS ticks to block for alert 255 * 256 * @note Multiple alerts can be raised simultaneously. The application should 257 * check for all alerts that have been enabled. 258 * 259 * @return 260 * - ESP_OK: Alerts read 261 * - ESP_ERR_TIMEOUT: Timed out waiting for alerts 262 * - ESP_ERR_INVALID_ARG: Arguments are invalid 263 * - ESP_ERR_INVALID_STATE: TWAI driver is not installed 264 */ 265 esp_err_t twai_read_alerts(uint32_t *alerts, TickType_t ticks_to_wait); 266 267 /** 268 * @brief Reconfigure which alerts are enabled 269 * 270 * This function reconfigures which alerts are enabled. If there are alerts 271 * which have not been read whilst reconfiguring, this function can read those 272 * alerts. 273 * 274 * @param[in] alerts_enabled Bit field of alerts to enable (see documentation for alert flags) 275 * @param[out] current_alerts Bit field of currently raised alerts. Set to NULL if unused 276 * 277 * @return 278 * - ESP_OK: Alerts reconfigured 279 * - ESP_ERR_INVALID_STATE: TWAI driver is not installed 280 */ 281 esp_err_t twai_reconfigure_alerts(uint32_t alerts_enabled, uint32_t *current_alerts); 282 283 /** 284 * @brief Start the bus recovery process 285 * 286 * This function initiates the bus recovery process when the TWAI driver is in 287 * the bus-off state. Once initiated, the TWAI driver will enter the recovering 288 * state and wait for 128 occurrences of the bus-free signal on the TWAI bus 289 * before returning to the stopped state. This function will reset the TX queue, 290 * clearing any messages pending transmission. 291 * 292 * @note The BUS_RECOVERED alert can be enabled to alert the application when 293 * the bus recovery process completes. 294 * 295 * @return 296 * - ESP_OK: Bus recovery started 297 * - ESP_ERR_INVALID_STATE: TWAI driver is not in the bus-off state, or is not installed 298 */ 299 esp_err_t twai_initiate_recovery(void); 300 301 /** 302 * @brief Get current status information of the TWAI driver 303 * 304 * @param[out] status_info Status information 305 * 306 * @return 307 * - ESP_OK: Status information retrieved 308 * - ESP_ERR_INVALID_ARG: Arguments are invalid 309 * - ESP_ERR_INVALID_STATE: TWAI driver is not installed 310 */ 311 esp_err_t twai_get_status_info(twai_status_info_t *status_info); 312 313 /** 314 * @brief Clear the transmit queue 315 * 316 * This function will clear the transmit queue of all messages. 317 * 318 * @note The transmit queue is automatically cleared when twai_stop() or 319 * twai_initiate_recovery() is called. 320 * 321 * @return 322 * - ESP_OK: Transmit queue cleared 323 * - ESP_ERR_INVALID_STATE: TWAI driver is not installed or TX queue is disabled 324 */ 325 esp_err_t twai_clear_transmit_queue(void); 326 327 /** 328 * @brief Clear the receive queue 329 * 330 * This function will clear the receive queue of all messages. 331 * 332 * @note The receive queue is automatically cleared when twai_start() is 333 * called. 334 * 335 * @return 336 * - ESP_OK: Transmit queue cleared 337 * - ESP_ERR_INVALID_STATE: TWAI driver is not installed 338 */ 339 esp_err_t twai_clear_receive_queue(void); 340 341 #ifdef __cplusplus 342 } 343 #endif 344 345 #endif //SOC_TWAI_SUPPORTED 346
