Merge branch 'feature/bt_a2dp_i2s' into 'master'

examples/bluetooth/a2dp_sink: add i2s audio to a2dp_sink example application

See merge request !853

examples/bluetooth/a2dp_sink/README.rst

@@ -11,4 +11,19 @@ Options choose step:
     3. enter menu Bluetooth, choose "Classic Bluetooth" and do not choose "Release DRAM from Classic BT controller"
     4. choose your options.
 
+For the I2S codec, pick whatever chip or board works for you; this code was written using a PCM5102 chip, but other I2S boards and chips will probably work as well. The default I2S connections are shown below, but these can be changed in menuconfig:
+
++-----------+--------------+
+| ESP pin   | I2S signal   |
++===========+==============+
+| GPIO22    | LRCK         |
++-----------+--------------+
+| GPIO25    | DATA         |
++-----------+--------------+
+| GPIO26    | BCK          |
++-----------+--------------+
+
+If the internal DAC is selected, analog audio will be available on GPIO25 and GPIO26. The output resolution on these pins will always be limited to 8 bit because of the internal structure of the DACs.
+
+
 After the program started, other bluetooth devices such as smart phones can discover this device named "ESP_SPEAKER", and after connection is established, audio data can be transmitted and there will occur a count of audio data packets printed.

examples/bluetooth/a2dp_sink/main/Kconfig.projbuild

@@ -0,0 +1,43 @@
+menu "A2DP Example Configuration"
+
+choice A2DP_SINK_OUTPUT
+    prompt "A2DP Sink Output"
+    default A2DP_SINK_OUTPUT_EXTERNAL_I2S
+    help
+        Select to use Internal DAC or external I2S driver
+
+config A2DP_SINK_OUTPUT_INTERNAL_DAC
+    bool "Internal DAC"
+    help
+        Select this to use Internal DAC sink output
+
+config A2DP_SINK_OUTPUT_EXTERNAL_I2S
+    bool "External I2S Codec"
+    help
+        Select this to use External I2S sink output
+
+endchoice
+
+config I2S_LRCK_PIN
+    int "I2S LRCK (WS) GPIO"
+    default 22
+    depends on A2DP_SINK_OUTPUT_EXTERNAL_I2S
+    help
+        GPIO number to use for I2S LRCK(WS) Driver.
+
+config I2S_BCK_PIN
+    int "I2S BCK GPIO"
+    default 26
+    depends on A2DP_SINK_OUTPUT_EXTERNAL_I2S
+    help
+        GPIO number to use for I2S BCK Driver.
+
+config I2S_DATA_PIN
+    int "I2S DATA GPIO"
+    default 25
+    depends on A2DP_SINK_OUTPUT_EXTERNAL_I2S
+    help
+        GPIO number to use for I2S Data Driver.
+
+
+endmenu

examples/bluetooth/a2dp_sink/main/bt_app_av.c

@@ -26,6 +26,10 @@
 #include "esp_a2dp_api.h"
 #include "esp_avrc_api.h"
 
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "driver/i2s.h"
+
 /* a2dp event handler */
 static void bt_av_hdl_a2d_evt(uint16_t event, void *p_param);
 /* avrc event handler */
@@ -53,6 +57,7 @@ void bt_app_a2d_cb(esp_a2d_cb_event_t event, esp_a2d_cb_param_t *param)
 
 void bt_app_a2d_data_cb(const uint8_t *data, uint32_t len)
 {
+    i2s_write_bytes(0, (const char *)data, len, portMAX_DELAY);
     if (++m_pkt_cnt % 100 == 0) {
         ESP_LOGE(BT_AV_TAG, "audio data pkt cnt %u", m_pkt_cnt);
     }
@@ -96,7 +101,23 @@ static void bt_av_hdl_a2d_evt(uint16_t event, void *p_param)
         ESP_LOGI(BT_AV_TAG, "a2dp audio_cfg_cb , codec type %d", a2d->audio_cfg.mcc.type);
         // for now only SBC stream is supported
         if (a2d->audio_cfg.mcc.type == ESP_A2D_MCT_SBC) {
-            ESP_LOGI(BT_AV_TAG, "audio player configured");
+            int sample_rate = 16000;
+            char oct0 = a2d->audio_cfg.mcc.cie.sbc[0];
+            if (oct0 & (0x01 << 6)) {
+                sample_rate = 32000;
+            } else if (oct0 & (0x01 << 5)) {
+                sample_rate = 44100;
+            } else if (oct0 & (0x01 << 4)) {
+                sample_rate = 48000;
+            }
+            i2s_set_clk(0, sample_rate, 16, 2);
+        
+            ESP_LOGI(BT_AV_TAG, "configure audio player %x-%x-%x-%x\n",
+                     a2d->audio_cfg.mcc.cie.sbc[0],
+                     a2d->audio_cfg.mcc.cie.sbc[1],
+                     a2d->audio_cfg.mcc.cie.sbc[2],
+                     a2d->audio_cfg.mcc.cie.sbc[3]);
+            ESP_LOGI(BT_AV_TAG, "audio player configured, samplerate=%d", sample_rate);
         }
         break;
     }

examples/bluetooth/a2dp_sink/main/main.c

@@ -31,6 +31,7 @@
 #include "esp_gap_bt_api.h"
 #include "esp_a2dp_api.h"
 #include "esp_avrc_api.h"
+#include "driver/i2s.h"
 
 /* event for handler "bt_av_hdl_stack_up */
 enum {
@@ -51,6 +52,37 @@ void app_main()
     }
     ESP_ERROR_CHECK( ret );
 
+    i2s_config_t i2s_config = {
+#ifdef CONFIG_A2DP_SINK_OUTPUT_INTERNAL_DAC
+        .mode = I2S_MODE_DAC_BUILT_IN,
+#else
+        .mode = I2S_MODE_MASTER | I2S_MODE_TX,                                  // Only TX
+#endif
+        .sample_rate = 44100,
+        .bits_per_sample = 16,                                              
+        .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,                           //2-channels
+        .communication_format = I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_MSB,
+        .dma_buf_count = 6,
+        .dma_buf_len = 60,                                                      //
+        .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1                                //Interrupt level 1
+    };
+
+
+    i2s_driver_install(0, &i2s_config, 0, NULL);
+#ifdef CONFIG_A2DP_SINK_OUTPUT_INTERNAL_DAC
+    i2s_set_pin(0, NULL);
+#else
+    i2s_pin_config_t pin_config = {
+        .bck_io_num = CONFIG_I2S_BCK_PIN,
+        .ws_io_num = CONFIG_I2S_LRCK_PIN,
+        .data_out_num = CONFIG_I2S_DATA_PIN,
+        .data_in_num = -1                                                       //Not used
+    };
+
+    i2s_set_pin(0, &pin_config);
+#endif
+
+
 
     esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
     if (esp_bt_controller_init(&bt_cfg) != ESP_OK) {

examples/bluetooth/a2dp_sink/sdkconfig.defaults

@@ -2,4 +2,3 @@
 # Classic BT is enabled and BT_DRAM_RELEASE is disabled
 CONFIG_BT_ENABLED=y
 CONFIG_CLASSIC_BT_ENABLED=y
-