Merge branch 'refactor/i2s_refactor_for_etm' into 'master'

refactor(i2s): refactor to use i2s etm controlling

Closes IDF-10508

See merge request espressif/esp-idf!32315

components/esp_driver_i2s/i2s_common.c

@@ -97,7 +97,9 @@ static void i2s_tx_channel_start(i2s_chan_handle_t handle)
     i2s_hal_tx_enable_dma(&(handle->controller->hal));
     i2s_hal_tx_start_link(&(handle->controller->hal), (uint32_t) handle->dma.desc[0]);
 #endif
-    i2s_hal_tx_start(&(handle->controller->hal));
+    if (!handle->is_etm_start) {
+        i2s_hal_tx_start(&(handle->controller->hal));
+    }
 }
 
 static void i2s_rx_channel_start(i2s_chan_handle_t handle)
@@ -117,12 +119,16 @@ static void i2s_rx_channel_start(i2s_chan_handle_t handle)
     i2s_hal_rx_enable_dma(&(handle->controller->hal));
     i2s_hal_rx_start_link(&(handle->controller->hal), (uint32_t) handle->dma.desc[0]);
 #endif
-    i2s_hal_rx_start(&(handle->controller->hal));
+    if (!handle->is_etm_start) {
+        i2s_hal_rx_start(&(handle->controller->hal));
+    }
 }
 
 static void i2s_tx_channel_stop(i2s_chan_handle_t handle)
 {
-    i2s_hal_tx_stop(&(handle->controller->hal));
+    if (!handle->is_etm_stop) {
+        i2s_hal_tx_stop(&(handle->controller->hal));
+    }
 #if SOC_GDMA_SUPPORTED
     gdma_stop(handle->dma.dma_chan);
 #else
@@ -135,7 +141,9 @@ static void i2s_tx_channel_stop(i2s_chan_handle_t handle)
 
 static void i2s_rx_channel_stop(i2s_chan_handle_t handle)
 {
-    i2s_hal_rx_stop(&(handle->controller->hal));
+    if (!handle->is_etm_stop) {
+        i2s_hal_rx_stop(&(handle->controller->hal));
+    }
 #if SOC_GDMA_SUPPORTED
     gdma_stop(handle->dma.dma_chan);
 #else

components/esp_driver_i2s/i2s_etm.c

@@ -21,15 +21,29 @@
 
 static const char *TAG = "i2s-etm";
 
-static esp_err_t i2s_del_etm_event(esp_etm_event_t *event)
+typedef struct {
+    esp_etm_task_t base;            /*!< Base ETM task object */
+    i2s_chan_handle_t handle;       /*!< I2S channel handle of this etm task */
+    i2s_etm_task_type_t task_type;  /*!< I2S ETM task type */
+} i2s_etm_task_t;
+
+static esp_err_t s_i2s_del_etm_event(esp_etm_event_t *event)
 {
     free(event);
     return ESP_OK;
 }
 
-static esp_err_t i2s_del_etm_task(esp_etm_task_t *task)
+static esp_err_t s_i2s_del_etm_task(esp_etm_task_t *task)
 {
-    free(task);
+    i2s_etm_task_t *i2s_task = __containerof(task, i2s_etm_task_t, base);
+    if (i2s_task->task_type == I2S_ETM_TASK_START) {
+        // The i2s start no longer be controlled by etm
+        i2s_task->handle->is_etm_start = false;
+    } else {
+        // The i2s stop no longer be controlled by etm
+        i2s_task->handle->is_etm_stop = false;
+    }
+    free(i2s_task);
     return ESP_OK;
 }
 
@@ -41,8 +55,11 @@ esp_err_t i2s_new_etm_event(i2s_chan_handle_t handle, const i2s_etm_event_config
     esp_etm_event_t *event = heap_caps_calloc(1, sizeof(esp_etm_event_t), ETM_MEM_ALLOC_CAPS);
     ESP_RETURN_ON_FALSE(event, ESP_ERR_NO_MEM, TAG, "no memory for ETM event");
 
+    // Get the event id from the I2S ETM event table
     uint32_t event_id = I2S_LL_ETM_EVENT_TABLE(handle->controller->id, handle->dir, config->event_type);
+    // If the event type is threshold, set the threshold to the hardware
     if (config->event_type == I2S_ETM_EVENT_REACH_THRESH) {
+        // Check if the threshold within the supported range
         ESP_GOTO_ON_FALSE(config->threshold <= I2S_LL_ETM_MAX_THRESH_NUM, ESP_ERR_INVALID_ARG, err, TAG,
                           "exceed the max threshold %"PRIu32, (uint32_t)I2S_LL_ETM_MAX_THRESH_NUM);
         if (handle->dir == I2S_DIR_TX) {
@@ -55,7 +72,7 @@ esp_err_t i2s_new_etm_event(i2s_chan_handle_t handle, const i2s_etm_event_config
     // fill the ETM event object
     event->event_id = event_id;
     event->trig_periph = ETM_TRIG_PERIPH_I2S;
-    event->del = i2s_del_etm_event;
+    event->del = s_i2s_del_etm_event;
     *out_event = event;
     return ret;
 err:
@@ -67,15 +84,26 @@ esp_err_t i2s_new_etm_task(i2s_chan_handle_t handle, const i2s_etm_task_config_t
 {
     ESP_RETURN_ON_FALSE(handle && config && out_task, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
     ESP_RETURN_ON_FALSE(config->task_type < I2S_ETM_TASK_MAX, ESP_ERR_INVALID_ARG, TAG, "invalid task type");
-    esp_etm_task_t *task = heap_caps_calloc(1, sizeof(esp_etm_task_t), ETM_MEM_ALLOC_CAPS);
+    i2s_etm_task_t *task = heap_caps_calloc(1, sizeof(i2s_etm_task_t), ETM_MEM_ALLOC_CAPS);
     ESP_RETURN_ON_FALSE(task, ESP_ERR_NO_MEM, TAG, "no memory for ETM task");
 
+    // Get the task id from the I2S ETM task table
     uint32_t task_id = I2S_LL_ETM_TASK_TABLE(handle->controller->id, handle->dir, config->task_type);
 
     // fill the ETM task object
-    task->task_id = task_id;
+    task->base.task_id = task_id;
-    task->trig_periph = ETM_TRIG_PERIPH_I2S;
+    task->base.trig_periph = ETM_TRIG_PERIPH_I2S;
-    task->del = i2s_del_etm_task;
+    task->base.del = s_i2s_del_etm_task;
-    *out_task = task;
+    task->handle = handle;
+    task->task_type = config->task_type;
+    if (config->task_type == I2S_ETM_TASK_START) {
+        // The i2s start will be controlled by etm
+        handle->is_etm_start = true;
+    } else {
+        // The i2s stop will be controlled by etm
+        handle->is_etm_stop = true;
+    }
+    *out_task = &(task->base);
+
     return ESP_OK;
 }

components/esp_driver_i2s/i2s_private.h

@@ -147,6 +147,8 @@ struct i2s_channel_obj_t {
     /* Stored configurations */
     int                     intr_prio_flags;/*!< i2s interrupt priority flags */
     void                    *mode_info;     /*!< Slot, clock and gpio information of each mode */
+    bool                    is_etm_start;   /*!< Whether start by etm tasks */
+    bool                    is_etm_stop;    /*!< Whether stop by etm tasks */
 #if SOC_I2S_SUPPORTS_APLL
     bool                    apll_en;        /*!< Flag of whether APLL enabled */
 #endif

components/esp_driver_i2s/test_apps/i2s/main/CMakeLists.txt

@@ -7,5 +7,5 @@ if(CONFIG_SOC_I2S_SUPPORTS_ETM AND CONFIG_SOC_GPIO_SUPPORT_ETM)
 endif()
 
 idf_component_register(SRCS ${srcs}
-                       PRIV_REQUIRES unity esp_driver_pcnt driver spi_flash esp_driver_gpio
+                       PRIV_REQUIRES unity esp_driver_pcnt spi_flash esp_driver_gpio esp_driver_i2s
                        WHOLE_ARCHIVE)

components/esp_driver_i2s/test_apps/i2s/main/test_i2s_etm.c

@@ -46,7 +46,7 @@ static void s_i2s_etm_check_status(void)
 }
 #endif  // ETM_LL_SUPPORT_STATUS
 
-static void s_i2s_init(uint8_t *buf)
+static void s_i2s_init(void *buf)
 {
     i2s_chan_config_t chan_cfg = I2S_CHANNEL_DEFAULT_CONFIG(I2S_NUM_AUTO, I2S_ROLE_MASTER);
     chan_cfg.dma_desc_num = TEST_DESC_NUM;
@@ -92,9 +92,11 @@ static void s_gpio_init(void)
 
 TEST_CASE("i2s_etm_event_test", "[etm]")
 {
-    uint8_t *buf = calloc(1, TEST_BUFF_SIZE);
+    uint32_t *buf = calloc(1, TEST_BUFF_SIZE);
     assert(buf);
-    memset(buf, 0x3C, TEST_BUFF_SIZE);
+    for (int i = 0; i < TEST_BUFF_SIZE / 4; i++) {
+        buf[i] = i;
+    }
 
     /* I2S init */
     s_i2s_init(buf);
@@ -153,9 +155,11 @@ TEST_CASE("i2s_etm_event_test", "[etm]")
 
 TEST_CASE("i2s_etm_task_test", "[etm]")
 {
-    uint8_t *buf = calloc(1, TEST_BUFF_SIZE);
+    uint32_t *buf = calloc(1, TEST_BUFF_SIZE);
     assert(buf);
-    memset(buf, 0x3C, TEST_BUFF_SIZE);
+    for (int i = 0; i < TEST_BUFF_SIZE / 4; i++) {
+        buf[i] = i;
+    }
 
     /* I2S init */
     s_i2s_init(buf);
@@ -165,39 +169,55 @@ TEST_CASE("i2s_etm_task_test", "[etm]")
 
     /* GPIO ETM event */
     gpio_etm_event_config_t gpio_event_cfg = {
-        .edge = GPIO_ETM_EVENT_EDGE_POS,
+        .edges = {GPIO_ETM_EVENT_EDGE_POS, GPIO_ETM_EVENT_EDGE_NEG},
     };
-    esp_etm_event_handle_t gpio_event_handle;
+    esp_etm_event_handle_t gpio_pos_event_handle;
-    TEST_ESP_OK(gpio_new_etm_event(&gpio_event_cfg, &gpio_event_handle));
+    esp_etm_event_handle_t gpio_neg_event_handle;
-    TEST_ESP_OK(gpio_etm_event_bind_gpio(gpio_event_handle, TEST_GPIO_ETM_NUM));
+    TEST_ESP_OK(gpio_new_etm_event(&gpio_event_cfg, &gpio_pos_event_handle, &gpio_neg_event_handle));
+    TEST_ESP_OK(gpio_etm_event_bind_gpio(gpio_pos_event_handle, TEST_GPIO_ETM_NUM));
+    TEST_ESP_OK(gpio_etm_event_bind_gpio(gpio_neg_event_handle, TEST_GPIO_ETM_NUM));
 
     /* I2S Task init */
-    i2s_etm_task_config_t i2s_task_cfg = {
+    i2s_etm_task_config_t i2s_start_task_cfg = {
+        .task_type = I2S_ETM_TASK_START,
+    };
+    esp_etm_task_handle_t i2s_start_task_handle;
+    TEST_ESP_OK(i2s_new_etm_task(s_tx_handle, &i2s_start_task_cfg, &i2s_start_task_handle));
+    i2s_etm_task_config_t i2s_stop_task_cfg = {
         .task_type = I2S_ETM_TASK_STOP,
     };
-    esp_etm_task_handle_t i2s_task_handle;
+    esp_etm_task_handle_t i2s_stop_task_handle;
-    TEST_ESP_OK(i2s_new_etm_task(s_tx_handle, &i2s_task_cfg, &i2s_task_handle));
+    TEST_ESP_OK(i2s_new_etm_task(s_tx_handle, &i2s_stop_task_cfg, &i2s_stop_task_handle));
 
     /* ETM connect */
     esp_etm_channel_config_t etm_config = {};
-    esp_etm_channel_handle_t etm_channel = NULL;
+    esp_etm_channel_handle_t i2s_etm_start_chan = NULL;
-    TEST_ESP_OK(esp_etm_new_channel(&etm_config, &etm_channel));
+    esp_etm_channel_handle_t i2s_etm_stop_chan = NULL;
-    TEST_ESP_OK(esp_etm_channel_connect(etm_channel, gpio_event_handle, i2s_task_handle));
+    TEST_ESP_OK(esp_etm_new_channel(&etm_config, &i2s_etm_start_chan));
-    TEST_ESP_OK(esp_etm_channel_enable(etm_channel));
+    TEST_ESP_OK(esp_etm_new_channel(&etm_config, &i2s_etm_stop_chan));
+    TEST_ESP_OK(esp_etm_channel_connect(i2s_etm_start_chan, gpio_pos_event_handle, i2s_start_task_handle));
+    TEST_ESP_OK(esp_etm_channel_connect(i2s_etm_stop_chan, gpio_neg_event_handle, i2s_stop_task_handle));
+    TEST_ESP_OK(esp_etm_channel_enable(i2s_etm_start_chan));
+    TEST_ESP_OK(esp_etm_channel_enable(i2s_etm_stop_chan));
     esp_etm_dump(stdout);
 
     TEST_ESP_OK(i2s_channel_enable(s_tx_handle));
     TEST_ESP_OK(i2s_channel_enable(s_rx_handle));
 
     /* Test */
-    // receive normally
+    // TX not started, read timeout
-    i2s_channel_read(s_rx_handle, buf, TEST_BUFF_SIZE, NULL, portMAX_DELAY);
+    TEST_ESP_ERR(ESP_ERR_TIMEOUT, i2s_channel_read(s_rx_handle, buf, TEST_BUFF_SIZE, NULL, 100));
-    // Set the GPIO to stop the I2S TX via ETM
+    // start TX via GPIO pos event
     TEST_ESP_OK(gpio_set_level(TEST_GPIO_ETM_NUM, 1));
+    // RX can receive data normally
+    TEST_ESP_OK(i2s_channel_read(s_rx_handle, buf, TEST_BUFF_SIZE, NULL, 100));
+    // Stop TX via GPIO neg event
+    TEST_ESP_OK(gpio_set_level(TEST_GPIO_ETM_NUM, 0));
+    // TX stopped, read will timeout when no legacy data in the queue
     esp_err_t ret = ESP_OK;
     // Receive will timeout after TX stopped
     for (int i = 0; i < 20 && ret == ESP_OK; i++) {
-        ret = i2s_channel_read(s_rx_handle, buf, TEST_BUFF_SIZE, NULL, 1000);
+        ret = i2s_channel_read(s_rx_handle, buf, TEST_BUFF_SIZE, NULL, 100);
     }
     TEST_ESP_ERR(ESP_ERR_TIMEOUT, ret);
 
@@ -206,10 +226,14 @@ TEST_CASE("i2s_etm_task_test", "[etm]")
     TEST_ESP_OK(i2s_channel_disable(s_tx_handle));
     free(buf);
 
-    TEST_ESP_OK(esp_etm_channel_disable(etm_channel));
+    TEST_ESP_OK(esp_etm_channel_disable(i2s_etm_start_chan));
-    TEST_ESP_OK(esp_etm_del_event(gpio_event_handle));
+    TEST_ESP_OK(esp_etm_channel_disable(i2s_etm_stop_chan));
-    TEST_ESP_OK(esp_etm_del_task(i2s_task_handle));
+    TEST_ESP_OK(esp_etm_del_event(gpio_pos_event_handle));
-    TEST_ESP_OK(esp_etm_del_channel(etm_channel));
+    TEST_ESP_OK(esp_etm_del_event(gpio_neg_event_handle));
+    TEST_ESP_OK(esp_etm_del_task(i2s_start_task_handle));
+    TEST_ESP_OK(esp_etm_del_task(i2s_stop_task_handle));
+    TEST_ESP_OK(esp_etm_del_channel(i2s_etm_start_chan));
+    TEST_ESP_OK(esp_etm_del_channel(i2s_etm_stop_chan));
 
     s_i2s_deinit();
 }

docs/en/api-reference/peripherals/etm.rst

@@ -72,6 +72,7 @@ Other Peripheral Events
     :SOC_MCPWM_SUPPORT_ETM: - Refer to :doc:`/api-reference/peripherals/mcpwm` for how to get the ETM event handle from MCPWM.
     :SOC_ANA_CMPR_SUPPORT_ETM: - Refer to :doc:`/api-reference/peripherals/ana_cmpr` for how to get the ETM event handle from analog comparator.
     :SOC_TEMPERATURE_SENSOR_SUPPORT_ETM: - Refer to :doc:`/api-reference/peripherals/temp_sensor` for how to get the ETM event handle from temperature sensor.
+    :SOC_I2S_SUPPORTS_ETM:  - Refer to :doc:`/api-reference/peripherals/i2s` for how to get the ETM event handle from I2S.
 
 .. _etm-task:
 
@@ -98,6 +99,7 @@ Other Peripheral Tasks
 
     :SOC_TIMER_SUPPORT_ETM: - Refer to :doc:`GPTimer </api-reference/peripherals/gptimer>` for how to get the ETM task handle from GPTimer.
     :SOC_TEMPERATURE_SENSOR_SUPPORT_ETM: - Refer to :doc:`/api-reference/peripherals/temp_sensor` for how to get the ETM task handle from temperature sensor.
+    :SOC_I2S_SUPPORTS_ETM:  - Refer to :doc:`/api-reference/peripherals/i2s` for how to get the ETM task handle from I2S.
 
 .. _etm-channel-control:
 

docs/en/api-reference/peripherals/i2s.rst

@@ -990,6 +990,79 @@ Here is an example of how to allocate a pair of full-duplex channels:
         i2s_channel_init_std_mode(rx_handle, &std_rx_cfg);
         i2s_channel_enable(rx_handle);
 
+.. only:: SOC_I2S_SUPPORTS_ETM
+
+    I2S ETM Usage
+    ^^^^^^^^^^^^^
+
+    {IDF_TARGET_NAME} supports I2S ETM (Event Task Matrix), which allows to trigger other ETM tasks via I2S ETM events, or to control the start/stop by I2S ETM tasks.
+
+    The I2S ETM APIs can be found in ``driver/i2s_etm.h``, the following example shows how to use GPIO to start/stop I2S channel via ETM:
+
+    .. code-block:: c
+
+        #include "driver/i2s_etm.h"
+        // ...
+        i2s_chan_handle_t tx_handle;
+        // Initialize I2S channel
+        // ......
+        int ctrl_gpio = 4;
+        // Initialize GPIO
+        // ......
+        /* Register GPIO ETM events */
+        gpio_etm_event_config_t gpio_event_cfg = {
+            .edges = {GPIO_ETM_EVENT_EDGE_POS, GPIO_ETM_EVENT_EDGE_NEG},
+        };
+        esp_etm_event_handle_t gpio_pos_event_handle;
+        esp_etm_event_handle_t gpio_neg_event_handle;
+        gpio_new_etm_event(&gpio_event_cfg, &gpio_pos_event_handle, &gpio_neg_event_handle);
+        gpio_etm_event_bind_gpio(gpio_pos_event_handle, ctrl_gpio);
+        gpio_etm_event_bind_gpio(gpio_neg_event_handle, ctrl_gpio);
+        /* Register I2S ETM tasks */
+        i2s_etm_task_config_t i2s_start_task_cfg = {
+            .task_type = I2S_ETM_TASK_START,
+        };
+        esp_etm_task_handle_t i2s_start_task_handle;
+        i2s_new_etm_task(tx_handle, &i2s_start_task_cfg, &i2s_start_task_handle);
+        i2s_etm_task_config_t i2s_stop_task_cfg = {
+            .task_type = I2S_ETM_TASK_STOP,
+        };
+        esp_etm_task_handle_t i2s_stop_task_handle;
+        i2s_new_etm_task(tx_handle, &i2s_stop_task_cfg, &i2s_stop_task_handle);
+        /* Bind GPIO events to I2S ETM tasks */
+        esp_etm_channel_config_t etm_config = {};
+        esp_etm_channel_handle_t i2s_etm_start_chan = NULL;
+        esp_etm_channel_handle_t i2s_etm_stop_chan = NULL;
+        esp_etm_new_channel(&etm_config, &i2s_etm_start_chan);
+        esp_etm_new_channel(&etm_config, &i2s_etm_stop_chan);
+        esp_etm_channel_connect(i2s_etm_start_chan, gpio_pos_event_handle, i2s_start_task_handle);
+        esp_etm_channel_connect(i2s_etm_stop_chan, gpio_neg_event_handle, i2s_stop_task_handle);
+        esp_etm_channel_enable(i2s_etm_start_chan);
+        esp_etm_channel_enable(i2s_etm_stop_chan);
+        /* Enable I2S channel first before starting I2S channel */
+        i2s_channel_enable(tx_handle);
+        // (Optional) Able to load the data into the internal DMA buffer here,
+        // but tx_channel does not start yet, will timeout when the internal buffer is full
+        // i2s_channel_write(tx_handle, data, data_size, NULL, 0);
+        /* Start I2S channel by setting the GPIO to high */
+        gpio_set_level(ctrl_gpio, 1);
+        // Write data ......
+        // i2s_channel_write(tx_handle, data, data_size, NULL, 1000);
+        /* Stop I2S channel by setting the GPIO to low */
+        gpio_set_level(ctrl_gpio, 0);
+
+        /* Free resources */
+        i2s_channel_disable(tx_handle);
+        esp_etm_channel_disable(i2s_etm_start_chan);
+        esp_etm_channel_disable(i2s_etm_stop_chan);
+        esp_etm_del_event(gpio_pos_event_handle);
+        esp_etm_del_event(gpio_neg_event_handle);
+        esp_etm_del_task(i2s_start_task_handle);
+        esp_etm_del_task(i2s_stop_task_handle);
+        esp_etm_del_channel(i2s_etm_start_chan);
+        esp_etm_del_channel(i2s_etm_stop_chan);
+        // De-initialize I2S and GPIO
+        // ......
 
 Application Notes
 -----------------

docs/zh_CN/api-reference/peripherals/etm.rst

@@ -72,6 +72,7 @@ GPIO **边沿** 事件是最常见的事件类型，任何 GPIO 管脚均可触
     :SOC_MCPWM_SUPPORT_ETM: - 要了解如何从 MCPWM 中获取 ETM 事件句柄，请参阅 :doc:`/api-reference/peripherals/mcpwm`。
     :SOC_ANA_CMPR_SUPPORT_ETM: - 要了解如何从模拟比较器获取 ETM 事件句柄，请参阅 :doc:`/api-reference/peripherals/ana_cmpr`。
     :SOC_TEMPERATURE_SENSOR_SUPPORT_ETM: - 要了解如何从温度传感器获取 ETM 事件句柄，请参阅 :doc:`/api-reference/peripherals/temp_sensor`。
+    :SOC_I2S_SUPPORTS_ETM:  - 要了解如何从 I2S 获取 ETM 事件句柄，请参阅 :doc:`/api-reference/peripherals/i2s`。
 
 .. _etm-task:
 
@@ -98,6 +99,7 @@ GPIO 任务是最常见的任务类型。一个 GPIO 可以采取一个或多个
 
     :SOC_TIMER_SUPPORT_ETM: - 要了解如何从 GPTimer 获取 ETM 任务句柄，请参阅 :doc:`/api-reference/peripherals/gptimer`。
     :SOC_TEMPERATURE_SENSOR_SUPPORT_ETM: - 要了解如何从温度传感器获取 ETM 任务句柄，请参阅 :doc:`/api-reference/peripherals/temp_sensor`。
+    :SOC_I2S_SUPPORTS_ETM:  - 要了解如何从 I2S 获取 ETM 任务句柄，请参阅 :doc:`/api-reference/peripherals/i2s`。
 
 .. _etm-channel-control:
 

docs/zh_CN/api-reference/peripherals/i2s.rst

@@ -990,6 +990,79 @@ STD RX 模式
         i2s_channel_init_std_mode(rx_handle, &std_rx_cfg);
         i2s_channel_enable(rx_handle);
 
+.. only:: SOC_I2S_SUPPORTS_ETM
+
+    I2S ETM 用法
+    ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+    {IDF_TARGET_NAME} 支持 I2S ETM （Event Task Matrix，事件任务矩阵）。 它可以通过 I2S 事件触发一个其他的 ETM 任务，或者通过其他的 ETM 事件来控制 I2S 的启停任务。
+
+    头文件 ``driver/i2s_etm.h`` 中可以找到 I2S ETM 所需的接口函数，下面示例代码将展示如何通过 GPIO 的 ETM 事件控制 I2S 的启停。
+
+    .. code-block:: c
+
+        #include "driver/i2s_etm.h"
+        // ...
+        i2s_chan_handle_t tx_handle;
+        // 初始化 I2S 通道
+        // ......
+        int ctrl_gpio = 4;
+        // 初始化 GPIO 用于控制
+        // ......
+        /* 注册 GPIO ETM 事件 */
+        gpio_etm_event_config_t gpio_event_cfg = {
+            .edges = {GPIO_ETM_EVENT_EDGE_POS, GPIO_ETM_EVENT_EDGE_NEG},
+        };
+        esp_etm_event_handle_t gpio_pos_event_handle;
+        esp_etm_event_handle_t gpio_neg_event_handle;
+        gpio_new_etm_event(&gpio_event_cfg, &gpio_pos_event_handle, &gpio_neg_event_handle);
+        gpio_etm_event_bind_gpio(gpio_pos_event_handle, ctrl_gpio);
+        gpio_etm_event_bind_gpio(gpio_neg_event_handle, ctrl_gpio);
+        /* 注册 I2S ETM 任务 */
+        i2s_etm_task_config_t i2s_start_task_cfg = {
+            .task_type = I2S_ETM_TASK_START,
+        };
+        esp_etm_task_handle_t i2s_start_task_handle;
+        i2s_new_etm_task(tx_handle, &i2s_start_task_cfg, &i2s_start_task_handle);
+        i2s_etm_task_config_t i2s_stop_task_cfg = {
+            .task_type = I2S_ETM_TASK_STOP,
+        };
+        esp_etm_task_handle_t i2s_stop_task_handle;
+        i2s_new_etm_task(tx_handle, &i2s_stop_task_cfg, &i2s_stop_task_handle);
+        /* 绑定 GPIO 事件和 I2S ETM 任务 */
+        esp_etm_channel_config_t etm_config = {};
+        esp_etm_channel_handle_t i2s_etm_start_chan = NULL;
+        esp_etm_channel_handle_t i2s_etm_stop_chan = NULL;
+        esp_etm_new_channel(&etm_config, &i2s_etm_start_chan);
+        esp_etm_new_channel(&etm_config, &i2s_etm_stop_chan);
+        esp_etm_channel_connect(i2s_etm_start_chan, gpio_pos_event_handle, i2s_start_task_handle);
+        esp_etm_channel_connect(i2s_etm_stop_chan, gpio_neg_event_handle, i2s_stop_task_handle);
+        esp_etm_channel_enable(i2s_etm_start_chan);
+        esp_etm_channel_enable(i2s_etm_stop_chan);
+        /* 通过 ETM 启动 I2S 前需要先使能这个通道 */
+        i2s_channel_enable(tx_handle);
+        // （可选）这里可以把要发送的数据先加载到内部的发送缓冲区中
+        // 但是由于 tx_channel 还没有启动，所以当内部缓冲区加载满后，再写入会超时
+        // i2s_channel_write(tx_handle, data, data_size, NULL, 0);
+        /* 通过拉高 GPIO 启动 I2S tx 通道 */
+        gpio_set_level(ctrl_gpio, 1);
+        // 写数据 ......
+        // i2s_channel_write(tx_handle, data, data_size, NULL, 1000);
+        /* 通过拉低 GPIO 停止 I2S tx 通道 */
+        gpio_set_level(ctrl_gpio, 0);
+
+        /* 释放 ETM 相关资源 */
+        i2s_channel_disable(tx_handle);
+        esp_etm_channel_disable(i2s_etm_start_chan);
+        esp_etm_channel_disable(i2s_etm_stop_chan);
+        esp_etm_del_event(gpio_pos_event_handle);
+        esp_etm_del_event(gpio_neg_event_handle);
+        esp_etm_del_task(i2s_start_task_handle);
+        esp_etm_del_task(i2s_stop_task_handle);
+        esp_etm_del_channel(i2s_etm_start_chan);
+        esp_etm_del_channel(i2s_etm_stop_chan);
+        // 去初始化 I2S 和 GPIO
+        // ......
 
 应用注意事项
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