docs(i2s): update programming guide for I2S ETM feature

components/esp_driver_i2s/i2s_private.h

@@ -147,8 +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/stop by etm tasks */
+    bool                    is_etm_start;   /*!< Whether start by etm tasks */
-    bool                    is_etm_stop;    /*!< Whether start/stop 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

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

@@ -979,6 +979,79 @@ 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

@@ -979,6 +979,79 @@ 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
 ------------