/*
* SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include "sdkconfig.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "freertos/semphr.h"
#include "freertos/idf_additions.h"
#include "esp_types.h"
#include "esp_log.h"
#include "esp_intr_alloc.h"
#include "esp_pm.h"
#include "esp_attr.h"
#include "esp_heap_caps.h"
#include "esp_clk_tree.h"
#include "clk_ctrl_os.h"
#include "driver/gpio.h"
#include "esp_private/periph_ctrl.h"
#include "esp_private/esp_clk.h"
#include "driver/twai.h"
#include "soc/soc_caps.h"
#include "soc/soc.h"
#include "soc/twai_periph.h"
#include "soc/gpio_sig_map.h"
#include "hal/twai_hal.h"
#include "esp_rom_gpio.h"
/* ---------------------------- Definitions --------------------------------- */
//Internal Macros
#define TWAI_CHECK(cond, ret_val) ({ \
if (!(cond)) { \
return (ret_val); \
} \
})
#define TWAI_CHECK_FROM_CRIT(cond, ret_val) ({ \
if (!(cond)) { \
TWAI_EXIT_CRITICAL(); \
return ret_val; \
} \
})
#define TWAI_SET_FLAG(var, mask) ((var) |= (mask))
#define TWAI_RESET_FLAG(var, mask) ((var) &= ~(mask))
#ifdef CONFIG_TWAI_ISR_IN_IRAM
#define TWAI_MALLOC_CAPS (MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT)
#else
#define TWAI_TAG "TWAI"
#define TWAI_MALLOC_CAPS MALLOC_CAP_DEFAULT
#endif //CONFIG_TWAI_ISR_IN_IRAM
#define DRIVER_DEFAULT_INTERRUPTS 0xE7 //Exclude data overrun (bit[3]) and brp_div (bit[4])
#define ALERT_LOG_LEVEL_WARNING TWAI_ALERT_ARB_LOST //Alerts above and including this level use ESP_LOGW
#define ALERT_LOG_LEVEL_ERROR TWAI_ALERT_TX_FAILED //Alerts above and including this level use ESP_LOGE
#if !SOC_RCC_IS_INDEPENDENT
#define TWAI_RCC_ATOMIC() PERIPH_RCC_ATOMIC()
#else
#define TWAI_RCC_ATOMIC()
#endif
/* ------------------ Typedefs, structures, and variables ------------------- */
//Control structure for TWAI driver
typedef struct {
int controller_id;
//Control and status members
twai_state_t state;
twai_mode_t mode;
uint32_t rx_missed_count;
uint32_t rx_overrun_count;
uint32_t tx_failed_count;
uint32_t arb_lost_count;
uint32_t bus_error_count;
intr_handle_t isr_handle;
//TX and RX
QueueHandle_t tx_queue;
QueueHandle_t rx_queue;
int tx_msg_count;
int rx_msg_count;
//Alerts
SemaphoreHandle_t alert_semphr;
uint32_t alerts_enabled;
uint32_t alerts_triggered;
//Power Management Lock
esp_pm_lock_handle_t pm_lock;
} twai_obj_t;
static twai_obj_t *p_twai_obj = NULL;
static portMUX_TYPE twai_spinlock = portMUX_INITIALIZER_UNLOCKED;
#define TWAI_ENTER_CRITICAL_ISR() portENTER_CRITICAL_ISR(&twai_spinlock)
#define TWAI_EXIT_CRITICAL_ISR() portEXIT_CRITICAL_ISR(&twai_spinlock)
#define TWAI_ENTER_CRITICAL() portENTER_CRITICAL(&twai_spinlock)
#define TWAI_EXIT_CRITICAL() portEXIT_CRITICAL(&twai_spinlock)
static twai_hal_context_t twai_context;
/* -------------------- Interrupt and Alert Handlers ------------------------ */
static void twai_alert_handler(uint32_t alert_code, int *alert_req)
{
if (p_twai_obj->alerts_enabled & alert_code) {
//Signify alert has occurred
TWAI_SET_FLAG(p_twai_obj->alerts_triggered, alert_code);
*alert_req = 1;
#ifndef CONFIG_TWAI_ISR_IN_IRAM //Only log if ISR is not in IRAM
if (p_twai_obj->alerts_enabled & TWAI_ALERT_AND_LOG) {
if (alert_code >= ALERT_LOG_LEVEL_ERROR) {
ESP_EARLY_LOGE(TWAI_TAG, "Alert %d", alert_code);
} else if (alert_code >= ALERT_LOG_LEVEL_WARNING) {
ESP_EARLY_LOGW(TWAI_TAG, "Alert %d", alert_code);
} else {
ESP_EARLY_LOGI(TWAI_TAG, "Alert %d", alert_code);
}
}
#endif //CONFIG_TWAI_ISR_IN_IRAM
}
}
static inline void twai_handle_rx_buffer_frames(BaseType_t *task_woken, int *alert_req)
{
#ifdef SOC_TWAI_SUPPORTS_RX_STATUS
uint32_t msg_count = twai_hal_get_rx_msg_count(&twai_context);
for (uint32_t i = 0; i < msg_count; i++) {
twai_hal_frame_t frame;
if (twai_hal_read_rx_buffer_and_clear(&twai_context, &frame)) {
//Valid frame copied from RX buffer
if (xQueueSendFromISR(p_twai_obj->rx_queue, &frame, task_woken) == pdTRUE) {
p_twai_obj->rx_msg_count++;
twai_alert_handler(TWAI_ALERT_RX_DATA, alert_req);
} else { //Failed to send to queue
p_twai_obj->rx_missed_count++;
twai_alert_handler(TWAI_ALERT_RX_QUEUE_FULL, alert_req);
}
} else { //Failed to read from RX buffer because message is overrun
p_twai_obj->rx_overrun_count++;
twai_alert_handler(TWAI_ALERT_RX_FIFO_OVERRUN, alert_req);
}
}
#else //SOC_TWAI_SUPPORTS_RX_STATUS
uint32_t msg_count = twai_hal_get_rx_msg_count(&twai_context);
bool overrun = false;
//Clear all valid RX frames
for (int i = 0; i < msg_count; i++) {
twai_hal_frame_t frame;
if (twai_hal_read_rx_buffer_and_clear(&twai_context, &frame)) {
//Valid frame copied from RX buffer
if (xQueueSendFromISR(p_twai_obj->rx_queue, &frame, task_woken) == pdTRUE) {
p_twai_obj->rx_msg_count++;
twai_alert_handler(TWAI_ALERT_RX_DATA, alert_req);
} else {
p_twai_obj->rx_missed_count++;
twai_alert_handler(TWAI_ALERT_RX_QUEUE_FULL, alert_req);
}
} else {
overrun = true;
break;
}
}
//All remaining frames are treated as overrun. Clear them all
if (overrun) {
p_twai_obj->rx_overrun_count += twai_hal_clear_rx_fifo_overrun(&twai_context);
twai_alert_handler(TWAI_ALERT_RX_FIFO_OVERRUN, alert_req);
}
#endif //SOC_TWAI_SUPPORTS_RX_STATUS
}
static inline void twai_handle_tx_buffer_frame(BaseType_t *task_woken, int *alert_req)
{
//Handle previously transmitted frame
if (twai_hal_check_last_tx_successful(&twai_context)) {
twai_alert_handler(TWAI_ALERT_TX_SUCCESS, alert_req);
} else {
p_twai_obj->tx_failed_count++;
twai_alert_handler(TWAI_ALERT_TX_FAILED, alert_req);
}
//Update TX message count
p_twai_obj->tx_msg_count--;
assert(p_twai_obj->tx_msg_count >= 0); //Sanity check
//Check if there are more frames to transmit
if (p_twai_obj->tx_msg_count > 0 && p_twai_obj->tx_queue != NULL) {
twai_hal_frame_t frame;
int res = xQueueReceiveFromISR(p_twai_obj->tx_queue, &frame, task_woken);
if (res == pdTRUE) {
twai_hal_set_tx_buffer_and_transmit(&twai_context, &frame);
} else {
assert(false && "failed to get a frame from TX queue");
}
} else {
//No more frames to transmit
twai_alert_handler(TWAI_ALERT_TX_IDLE, alert_req);
}
}
static void twai_intr_handler_main(void *arg)
{
BaseType_t task_woken = pdFALSE;
int alert_req = 0;
uint32_t events;
TWAI_ENTER_CRITICAL_ISR();
if (p_twai_obj == NULL) { //In case intr occurs whilst driver is being uninstalled
TWAI_EXIT_CRITICAL_ISR();
return;
}
events = twai_hal_get_events(&twai_context); //Get the events that triggered the interrupt
#if defined(CONFIG_TWAI_ERRATA_FIX_RX_FRAME_INVALID) || defined(CONFIG_TWAI_ERRATA_FIX_RX_FIFO_CORRUPT)
if (events & TWAI_HAL_EVENT_NEED_PERIPH_RESET) {
twai_hal_prepare_for_reset(&twai_context);
TWAI_RCC_ATOMIC() {
twai_ll_reset_register(p_twai_obj->controller_id);
}
twai_hal_recover_from_reset(&twai_context);
p_twai_obj->rx_missed_count += twai_hal_get_reset_lost_rx_cnt(&twai_context);
twai_alert_handler(TWAI_ALERT_PERIPH_RESET, &alert_req);
}
#endif
if (events & TWAI_HAL_EVENT_RX_BUFF_FRAME) {
//Note: This event will never occur if there is a periph reset event
twai_handle_rx_buffer_frames(&task_woken, &alert_req);
}
if (events & TWAI_HAL_EVENT_TX_BUFF_FREE) {
twai_handle_tx_buffer_frame(&task_woken, &alert_req);
}
//Handle events that only require alerting (i.e. no handler)
if (events & TWAI_HAL_EVENT_BUS_OFF) {
p_twai_obj->state = TWAI_STATE_BUS_OFF;
twai_alert_handler(TWAI_ALERT_BUS_OFF, &alert_req);
}
if (events & TWAI_HAL_EVENT_BUS_RECOV_CPLT) {
p_twai_obj->state = TWAI_STATE_STOPPED;
twai_alert_handler(TWAI_ALERT_BUS_RECOVERED, &alert_req);
}
if (events & TWAI_HAL_EVENT_BUS_ERR) {
p_twai_obj->bus_error_count++;
twai_alert_handler(TWAI_ALERT_BUS_ERROR, &alert_req);
}
if (events & TWAI_HAL_EVENT_ARB_LOST) {
p_twai_obj->arb_lost_count++;
twai_alert_handler(TWAI_ALERT_ARB_LOST, &alert_req);
}
if (events & TWAI_HAL_EVENT_BUS_RECOV_PROGRESS) {
//Bus-recovery in progress. TEC has dropped below error warning limit
twai_alert_handler(TWAI_ALERT_RECOVERY_IN_PROGRESS, &alert_req);
}
if (events & TWAI_HAL_EVENT_ERROR_PASSIVE) {
//Entered error passive
twai_alert_handler(TWAI_ALERT_ERR_PASS, &alert_req);
}
if (events & TWAI_HAL_EVENT_ERROR_ACTIVE) {
//Returned to error active
twai_alert_handler(TWAI_ALERT_ERR_ACTIVE, &alert_req);
}
if (events & TWAI_HAL_EVENT_ABOVE_EWL) {
//TEC or REC surpassed error warning limit
twai_alert_handler(TWAI_ALERT_ABOVE_ERR_WARN, &alert_req);
}
if (events & TWAI_HAL_EVENT_BELOW_EWL) {
//TEC and REC are both below error warning
twai_alert_handler(TWAI_ALERT_BELOW_ERR_WARN, &alert_req);
}
TWAI_EXIT_CRITICAL_ISR();
if (p_twai_obj->alert_semphr != NULL && alert_req) {
//Give semaphore if alerts were triggered
xSemaphoreGiveFromISR(p_twai_obj->alert_semphr, &task_woken);
}
if (task_woken == pdTRUE) {
portYIELD_FROM_ISR();
}
}
/* -------------------------- Helper functions ----------------------------- */
static void twai_configure_gpio(gpio_num_t tx, gpio_num_t rx, gpio_num_t clkout, gpio_num_t bus_status)
{
// assert the GPIO number is not a negative number (shift operation on a negative number is undefined)
assert(tx >= 0 && rx >= 0);
int controller_id = p_twai_obj->controller_id;
// if TX and RX set to the same GPIO, which means we want to create a loop-back in the GPIO matrix
bool io_loop_back = (tx == rx);
gpio_config_t gpio_conf = {
.intr_type = GPIO_INTR_DISABLE,
.pull_down_en = false,
.pull_up_en = false,
};
//Set RX pin
gpio_conf.mode = GPIO_MODE_INPUT | (io_loop_back ? GPIO_MODE_OUTPUT : 0);
gpio_conf.pin_bit_mask = 1ULL << rx;
gpio_config(&gpio_conf);
esp_rom_gpio_connect_in_signal(rx, twai_controller_periph_signals.controllers[controller_id].rx_sig, false);
//Set TX pin
gpio_conf.mode = GPIO_MODE_OUTPUT | (io_loop_back ? GPIO_MODE_INPUT : 0);
gpio_conf.pin_bit_mask = 1ULL << tx;
gpio_config(&gpio_conf);
esp_rom_gpio_connect_out_signal(tx, twai_controller_periph_signals.controllers[controller_id].tx_sig, false, false);
//Configure output clock pin (Optional)
if (clkout >= 0 && clkout < GPIO_NUM_MAX) {
gpio_set_pull_mode(clkout, GPIO_FLOATING);
esp_rom_gpio_connect_out_signal(clkout, twai_controller_periph_signals.controllers[controller_id].clk_out_sig, false, false);
esp_rom_gpio_pad_select_gpio(clkout);
}
//Configure bus status pin (Optional)
if (bus_status >= 0 && bus_status < GPIO_NUM_MAX) {
gpio_set_pull_mode(bus_status, GPIO_FLOATING);
esp_rom_gpio_connect_out_signal(bus_status, twai_controller_periph_signals.controllers[controller_id].bus_off_sig, false, false);
esp_rom_gpio_pad_select_gpio(bus_status);
}
}
static void twai_free_driver_obj(twai_obj_t *p_obj)
{
//Free driver object and any dependent SW resources it uses (queues, semaphores, interrupts, PM locks etc)
#if CONFIG_PM_ENABLE
if (p_obj->pm_lock != NULL) {
ESP_ERROR_CHECK(esp_pm_lock_delete(p_obj->pm_lock));
}
#endif //CONFIG_PM_ENABLE
if (p_obj->isr_handle) {
ESP_ERROR_CHECK(esp_intr_free(p_obj->isr_handle));
}
//Delete queues and semaphores
if (p_obj->tx_queue != NULL) {
vQueueDeleteWithCaps(p_obj->tx_queue);
}
if (p_obj->rx_queue != NULL) {
vQueueDeleteWithCaps(p_obj->rx_queue);
}
if (p_obj->alert_semphr != NULL) {
vSemaphoreDeleteWithCaps(p_obj->alert_semphr);
}
heap_caps_free(p_obj);
}
static esp_err_t twai_alloc_driver_obj(const twai_general_config_t *g_config, twai_clock_source_t clk_src, int controller_id, twai_obj_t **p_twai_obj_ret)
{
//Allocate driver object and any dependent SW resources it uses (queues, semaphores, interrupts, PM locks etc)
esp_err_t ret;
//Create a TWAI driver object
twai_obj_t *p_obj = heap_caps_calloc(1, sizeof(twai_obj_t), TWAI_MALLOC_CAPS);
if (p_obj == NULL) {
return ESP_ERR_NO_MEM;
}
if (g_config->tx_queue_len > 0) {
p_obj->tx_queue = xQueueCreateWithCaps(g_config->tx_queue_len, sizeof(twai_hal_frame_t), TWAI_MALLOC_CAPS);
}
p_obj->rx_queue = xQueueCreateWithCaps(g_config->rx_queue_len, sizeof(twai_hal_frame_t), TWAI_MALLOC_CAPS);
p_obj->alert_semphr = xSemaphoreCreateBinaryWithCaps(TWAI_MALLOC_CAPS);
if ((g_config->tx_queue_len > 0 && p_obj->tx_queue == NULL) || p_obj->rx_queue == NULL || p_obj->alert_semphr == NULL) {
ret = ESP_ERR_NO_MEM;
goto err;
}
//Allocate interrupt
ret = esp_intr_alloc(twai_controller_periph_signals.controllers[controller_id].irq_id,
g_config->intr_flags | ESP_INTR_FLAG_INTRDISABLED,
twai_intr_handler_main,
NULL,
&p_obj->isr_handle);
if (ret != ESP_OK) {
goto err;
}
#if CONFIG_PM_ENABLE
#if SOC_TWAI_CLK_SUPPORT_APB
// DFS can change APB frequency. So add lock to prevent sleep and APB freq from changing
if (clk_src == TWAI_CLK_SRC_APB) {
// TODO: pm_lock name should also reflect the controller ID
ret = esp_pm_lock_create(ESP_PM_APB_FREQ_MAX, 0, "twai", &(p_obj->pm_lock));
if (ret != ESP_OK) {
goto err;
}
}
#else // XTAL
// XTAL freq can be closed in light sleep, so we need to create a lock to prevent light sleep
ret = esp_pm_lock_create(ESP_PM_NO_LIGHT_SLEEP, 0, "twai", &(p_obj->pm_lock));
if (ret != ESP_OK) {
goto err;
}
#endif //SOC_TWAI_CLK_SUPPORT_APB
#endif //CONFIG_PM_ENABLE
*p_twai_obj_ret = p_obj;
return ESP_OK;
err:
twai_free_driver_obj(p_obj);
return ret;
}
/* ---------------------------- Public Functions ---------------------------- */
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)
{
//Check arguments
TWAI_CHECK(g_config != NULL, ESP_ERR_INVALID_ARG);
TWAI_CHECK(t_config != NULL, ESP_ERR_INVALID_ARG);
TWAI_CHECK(f_config != NULL, ESP_ERR_INVALID_ARG);
TWAI_CHECK(g_config->rx_queue_len > 0, ESP_ERR_INVALID_ARG);
TWAI_CHECK(GPIO_IS_VALID_OUTPUT_GPIO(g_config->tx_io), ESP_ERR_INVALID_ARG);
TWAI_CHECK(GPIO_IS_VALID_GPIO(g_config->rx_io), ESP_ERR_INVALID_ARG);
#ifndef CONFIG_TWAI_ISR_IN_IRAM
TWAI_CHECK(!(g_config->intr_flags & ESP_INTR_FLAG_IRAM), ESP_ERR_INVALID_ARG);
#endif
TWAI_ENTER_CRITICAL();
TWAI_CHECK_FROM_CRIT(p_twai_obj == NULL, ESP_ERR_INVALID_STATE);
TWAI_EXIT_CRITICAL();
//Get clock source resolution
uint32_t clock_source_hz = 0;
twai_clock_source_t clk_src = t_config->clk_src;
//Fall back to default clock source
if (clk_src == 0) {
clk_src = TWAI_CLK_SRC_DEFAULT;
}
esp_clk_tree_src_get_freq_hz(clk_src, ESP_CLK_TREE_SRC_FREQ_PRECISION_CACHED, &clock_source_hz);
//Check brp validation
uint32_t brp = t_config->brp;
if (t_config->quanta_resolution_hz) {
TWAI_CHECK(clock_source_hz % t_config->quanta_resolution_hz == 0, ESP_ERR_INVALID_ARG);
brp = clock_source_hz / t_config->quanta_resolution_hz;
}
TWAI_CHECK(twai_ll_check_brp_validation(brp), ESP_ERR_INVALID_ARG);
esp_err_t ret;
twai_obj_t *p_twai_obj_dummy;
// TODO: Currently only controller 0 is supported by the driver. IDF-4775
const int controller_id = 0;
//Create a TWAI object (including queues, semaphores, interrupts, and PM locks)
ret = twai_alloc_driver_obj(g_config, clk_src, controller_id, &p_twai_obj_dummy);
if (ret != ESP_OK) {
return ret;
}
//Initialize flags and variables. All other members are already set to zero by twai_alloc_driver_obj()
p_twai_obj_dummy->controller_id = controller_id;
p_twai_obj_dummy->state = TWAI_STATE_STOPPED;
p_twai_obj_dummy->mode = g_config->mode;
p_twai_obj_dummy->alerts_enabled = g_config->alerts_enabled;
//Assign the TWAI object
TWAI_ENTER_CRITICAL();
if (p_twai_obj == NULL) {
p_twai_obj = p_twai_obj_dummy;
} else {
//Check if driver is already installed
TWAI_EXIT_CRITICAL();
ret = ESP_ERR_INVALID_STATE;
goto err;
}
//Enable TWAI peripheral register clock
TWAI_RCC_ATOMIC() {
twai_ll_enable_bus_clock(p_twai_obj->controller_id, true);
twai_ll_reset_register(p_twai_obj->controller_id);
}
//Initialize TWAI HAL layer
twai_hal_config_t hal_config = {
.clock_source_hz = clock_source_hz,
.controller_id = controller_id,
};
bool res = twai_hal_init(&twai_context, &hal_config);
assert(res);
twai_hal_configure(&twai_context, t_config, f_config, DRIVER_DEFAULT_INTERRUPTS, g_config->clkout_divider);
TWAI_EXIT_CRITICAL();
//Assign GPIO and Interrupts
twai_configure_gpio(g_config->tx_io, g_config->rx_io, g_config->clkout_io, g_config->bus_off_io);
#if CONFIG_PM_ENABLE
//Acquire PM lock
if (p_twai_obj->pm_lock) {
ESP_ERROR_CHECK(esp_pm_lock_acquire(p_twai_obj->pm_lock)); //Acquire pm_lock during the whole driver lifetime
}
#endif //CONFIG_PM_ENABLE
//Enable interrupt
ESP_ERROR_CHECK(esp_intr_enable(p_twai_obj->isr_handle));
return ESP_OK; //TWAI module is still in reset mode, users need to call twai_start() afterwards
err:
twai_free_driver_obj(p_twai_obj_dummy);
return ret;
}
esp_err_t twai_driver_uninstall(void)
{
twai_obj_t *p_twai_obj_dummy;
TWAI_ENTER_CRITICAL();
//Check state
TWAI_CHECK_FROM_CRIT(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK_FROM_CRIT(p_twai_obj->state == TWAI_STATE_STOPPED || p_twai_obj->state == TWAI_STATE_BUS_OFF, ESP_ERR_INVALID_STATE);
//Clear registers by reading
twai_hal_deinit(&twai_context);
TWAI_RCC_ATOMIC() {
twai_ll_enable_bus_clock(p_twai_obj->controller_id, false);
}
p_twai_obj_dummy = p_twai_obj; //Use dummy to shorten critical section
p_twai_obj = NULL;
TWAI_EXIT_CRITICAL();
#if CONFIG_PM_ENABLE
if (p_twai_obj_dummy->pm_lock) {
//Release and delete power management lock
ESP_ERROR_CHECK(esp_pm_lock_release(p_twai_obj_dummy->pm_lock));
}
#endif //CONFIG_PM_ENABLE
//Disable interrupt
ESP_ERROR_CHECK(esp_intr_disable(p_twai_obj_dummy->isr_handle));
//Free can driver object
twai_free_driver_obj(p_twai_obj_dummy);
return ESP_OK;
}
esp_err_t twai_start(void)
{
//Check state
TWAI_ENTER_CRITICAL();
TWAI_CHECK_FROM_CRIT(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK_FROM_CRIT(p_twai_obj->state == TWAI_STATE_STOPPED, ESP_ERR_INVALID_STATE);
//Reset RX queue, RX message count, amd TX queue
xQueueReset(p_twai_obj->rx_queue);
if (p_twai_obj->tx_queue != NULL) {
xQueueReset(p_twai_obj->tx_queue);
}
p_twai_obj->rx_msg_count = 0;
p_twai_obj->tx_msg_count = 0;
twai_hal_start(&twai_context, p_twai_obj->mode);
p_twai_obj->state = TWAI_STATE_RUNNING;
TWAI_EXIT_CRITICAL();
return ESP_OK;
}
esp_err_t twai_stop(void)
{
//Check state
TWAI_ENTER_CRITICAL();
TWAI_CHECK_FROM_CRIT(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK_FROM_CRIT(p_twai_obj->state == TWAI_STATE_RUNNING, ESP_ERR_INVALID_STATE);
twai_hal_stop(&twai_context);
//Reset TX Queue and message count
if (p_twai_obj->tx_queue != NULL) {
xQueueReset(p_twai_obj->tx_queue);
}
p_twai_obj->tx_msg_count = 0;
p_twai_obj->state = TWAI_STATE_STOPPED;
TWAI_EXIT_CRITICAL();
return ESP_OK;
}
esp_err_t twai_transmit(const twai_message_t *message, TickType_t ticks_to_wait)
{
//Check arguments
TWAI_CHECK(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK(message != NULL, ESP_ERR_INVALID_ARG);
TWAI_CHECK((message->data_length_code <= TWAI_FRAME_MAX_DLC) || message->dlc_non_comp, ESP_ERR_INVALID_ARG);
TWAI_ENTER_CRITICAL();
//Check State
TWAI_CHECK_FROM_CRIT(!(p_twai_obj->mode == TWAI_MODE_LISTEN_ONLY), ESP_ERR_NOT_SUPPORTED);
TWAI_CHECK_FROM_CRIT(p_twai_obj->state == TWAI_STATE_RUNNING, ESP_ERR_INVALID_STATE);
//Format frame
esp_err_t ret = ESP_FAIL;
twai_hal_frame_t tx_frame;
twai_hal_format_frame(message, &tx_frame);
//Check if frame can be sent immediately
if (p_twai_obj->tx_msg_count == 0) {
//No other frames waiting to transmit. Bypass queue and transmit immediately
twai_hal_set_tx_buffer_and_transmit(&twai_context, &tx_frame);
p_twai_obj->tx_msg_count++;
ret = ESP_OK;
}
TWAI_EXIT_CRITICAL();
if (ret != ESP_OK) {
if (p_twai_obj->tx_queue == NULL) {
//TX Queue is disabled and TX buffer is occupied, message was not sent
ret = ESP_FAIL;
} else if (xQueueSend(p_twai_obj->tx_queue, &tx_frame, ticks_to_wait) == pdTRUE) {
//Copied to TX Queue
TWAI_ENTER_CRITICAL();
if ((!twai_hal_check_state_flags(&twai_context, TWAI_HAL_STATE_FLAG_TX_BUFF_OCCUPIED)) && uxQueueMessagesWaiting(p_twai_obj->tx_queue) > 0) {
//If the TX buffer is free but the TX queue is not empty. Check if we need to manually start a transmission
if (twai_hal_check_state_flags(&twai_context, TWAI_HAL_STATE_FLAG_BUS_OFF) || !twai_hal_check_state_flags(&twai_context, TWAI_HAL_STATE_FLAG_RUNNING)) {
//TX buffer became free due to bus-off or is no longer running. No need to start a transmission
ret = ESP_ERR_INVALID_STATE;
} else {
//Manually start a transmission
int res = xQueueReceive(p_twai_obj->tx_queue, &tx_frame, 0);
assert(res == pdTRUE);
(void)res;
twai_hal_set_tx_buffer_and_transmit(&twai_context, &tx_frame);
p_twai_obj->tx_msg_count++;
ret = ESP_OK;
}
} else {
//Frame was copied to queue, waiting to be transmitted
p_twai_obj->tx_msg_count++;
ret = ESP_OK;
}
TWAI_EXIT_CRITICAL();
} else {
//Timed out waiting for free space on TX queue
ret = ESP_ERR_TIMEOUT;
}
}
return ret;
}
esp_err_t twai_receive(twai_message_t *message, TickType_t ticks_to_wait)
{
//Check arguments and state
TWAI_CHECK(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK(message != NULL, ESP_ERR_INVALID_ARG);
//Get frame from RX Queue or RX Buffer
twai_hal_frame_t rx_frame;
if (xQueueReceive(p_twai_obj->rx_queue, &rx_frame, ticks_to_wait) != pdTRUE) {
return ESP_ERR_TIMEOUT;
}
TWAI_ENTER_CRITICAL();
p_twai_obj->rx_msg_count--;
TWAI_EXIT_CRITICAL();
//Decode frame
twai_hal_parse_frame(&rx_frame, message);
return ESP_OK;
}
esp_err_t twai_read_alerts(uint32_t *alerts, TickType_t ticks_to_wait)
{
//Check arguments and state
TWAI_CHECK(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK(alerts != NULL, ESP_ERR_INVALID_ARG);
//Wait for an alert to occur
if (xSemaphoreTake(p_twai_obj->alert_semphr, ticks_to_wait) == pdTRUE) {
TWAI_ENTER_CRITICAL();
*alerts = p_twai_obj->alerts_triggered;
p_twai_obj->alerts_triggered = 0; //Clear triggered alerts
TWAI_EXIT_CRITICAL();
return ESP_OK;
} else {
*alerts = 0;
return ESP_ERR_TIMEOUT;
}
}
esp_err_t twai_reconfigure_alerts(uint32_t alerts_enabled, uint32_t *current_alerts)
{
TWAI_CHECK(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_ENTER_CRITICAL();
//Clear any unhandled alerts
if (current_alerts != NULL) {
*current_alerts = p_twai_obj->alerts_triggered;
}
p_twai_obj->alerts_triggered = 0;
p_twai_obj->alerts_enabled = alerts_enabled; //Update enabled alerts
TWAI_EXIT_CRITICAL();
return ESP_OK;
}
esp_err_t twai_initiate_recovery(void)
{
TWAI_ENTER_CRITICAL();
//Check state
TWAI_CHECK_FROM_CRIT(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK_FROM_CRIT(p_twai_obj->state == TWAI_STATE_BUS_OFF, ESP_ERR_INVALID_STATE);
//Reset TX Queue/Counters
if (p_twai_obj->tx_queue != NULL) {
xQueueReset(p_twai_obj->tx_queue);
}
p_twai_obj->tx_msg_count = 0;
//Trigger start of recovery process
twai_hal_start_bus_recovery(&twai_context);
p_twai_obj->state = TWAI_STATE_RECOVERING;
TWAI_EXIT_CRITICAL();
return ESP_OK;
}
esp_err_t twai_get_status_info(twai_status_info_t *status_info)
{
//Check parameters and state
TWAI_CHECK(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK(status_info != NULL, ESP_ERR_INVALID_ARG);
TWAI_ENTER_CRITICAL();
if (p_twai_obj->mode == TWAI_MODE_LISTEN_ONLY) {
//Error counters are frozen under listen only mode thus are meaningless. Simply return 0 in this case.
status_info->tx_error_counter = 0;
status_info->rx_error_counter = 0;
} else {
status_info->tx_error_counter = twai_hal_get_tec(&twai_context);
status_info->rx_error_counter = twai_hal_get_rec(&twai_context);
}
status_info->msgs_to_tx = p_twai_obj->tx_msg_count;
status_info->msgs_to_rx = p_twai_obj->rx_msg_count;
status_info->tx_failed_count = p_twai_obj->tx_failed_count;
status_info->rx_missed_count = p_twai_obj->rx_missed_count;
status_info->rx_overrun_count = p_twai_obj->rx_overrun_count;
status_info->arb_lost_count = p_twai_obj->arb_lost_count;
status_info->bus_error_count = p_twai_obj->bus_error_count;
status_info->state = p_twai_obj->state;
TWAI_EXIT_CRITICAL();
return ESP_OK;
}
esp_err_t twai_clear_transmit_queue(void)
{
//Check State
TWAI_CHECK(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_CHECK(p_twai_obj->tx_queue != NULL, ESP_ERR_NOT_SUPPORTED);
TWAI_ENTER_CRITICAL();
//If a message is currently undergoing transmission, the tx interrupt handler will decrement tx_msg_count
p_twai_obj->tx_msg_count = twai_hal_check_state_flags(&twai_context, TWAI_HAL_STATE_FLAG_TX_BUFF_OCCUPIED) ? 1 : 0;
xQueueReset(p_twai_obj->tx_queue);
TWAI_EXIT_CRITICAL();
return ESP_OK;
}
esp_err_t twai_clear_receive_queue(void)
{
//Check State
TWAI_CHECK(p_twai_obj != NULL, ESP_ERR_INVALID_STATE);
TWAI_ENTER_CRITICAL();
p_twai_obj->rx_msg_count = 0;
xQueueReset(p_twai_obj->rx_queue);
TWAI_EXIT_CRITICAL();
return ESP_OK;
}