stereo audio output and software volume control

.gitlab-ci.yml

@@ -10,6 +10,8 @@ default:
   # built via:
   #     docker load < $(nix-build nix/docker-image.nix)
   image: registry.gitlab.com/flow3r-badge/flow3r-build:kfjixcricw2358zp5vg15b784l9jnpzz
+  before_script:
+    - sed -i 's/clk_info->bclk_div = 8;/clk_info->bclk_div = 13;/g' $IDF_PATH/components/driver/i2s/i2s_pdm.c
 
 build:
   stage: build

components/flow3r_bsp/flow3r_bsp_audio.c

@@ -2,53 +2,75 @@
 
 #include <string.h>
 
-#include "driver/i2s.h"
+#include "driver/i2s_pdm.h"
 #include "esp_log.h"
 
+i2s_chan_handle_t tx_handle;
+
 esp_err_t flow3r_bsp_audio_write(const void *src, size_t size,
                                  size_t *bytes_written,
                                  TickType_t ticks_to_wait) {
-    return i2s_write(0, src, size, bytes_written, ticks_to_wait);
+    return i2s_channel_write(tx_handle, src, size, bytes_written, ticks_to_wait);
 }
 
 #include "flow3r_bsp_max98091.h"
 
-// TODO: rewrite to new driver, enable stereo
+// copied from ESP-IDF 5.2
+#define I2S_PDM_TX_SLOT_DAC_DEFAULT_CONFIG(bits_per_sample, mono_or_stereo) { \
+    .data_bit_width = bits_per_sample, \
+    .slot_bit_width = I2S_SLOT_BIT_WIDTH_AUTO, \
+    .slot_mode = mono_or_stereo, \
+    .sd_prescale = 0, \
+    .sd_scale = I2S_PDM_SIG_SCALING_MUL_1, \
+    .hp_scale = I2S_PDM_SIG_SCALING_MUL_1, \
+    .lp_scale = I2S_PDM_SIG_SCALING_MUL_1, \
+    .sinc_scale = I2S_PDM_SIG_SCALING_MUL_1, \
+    .line_mode = ((mono_or_stereo) == I2S_SLOT_MODE_MONO ? \
+                 I2S_PDM_TX_ONE_LINE_DAC : I2S_PDM_TX_TWO_LINE_DAC), \
+    .hp_en = true, \
+    .hp_cut_off_freq_hz = 35.5, \
+    .sd_dither = 0, \
+    .sd_dither2 = 1, \
+}
+
+#define I2S_PDM_TX_CLK_DAC_DEFAULT_CONFIG(rate) { \
+    .sample_rate_hz = rate, \
+    .clk_src = I2S_CLK_SRC_DEFAULT, \
+    .mclk_multiple = I2S_MCLK_MULTIPLE_256, \
+    .up_sample_fp = 960, \
+    .up_sample_fs = (rate) / 100, \
+}
+//  .bclk_div = 13,
 
 void flow3r_bsp_audio_init(void) {
     //flow3r_bsp_max98091_init();
     //vTaskDelay(100 / portTICK_PERIOD_MS);  // dunno if necessary
-    static const i2s_config_t i2s_config = {
-        .mode = I2S_MODE_MASTER | I2S_MODE_TX | I2S_MODE_PDM,
-        .sample_rate = FLOW3R_BSP_AUDIO_SAMPLE_RATE,
-        .bits_per_sample = 16,
-        .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
-        .communication_format = I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_LSB,
-        .intr_alloc_flags = 0,  // default interrupt priority
-        .dma_buf_count = FLOW3R_BSP_AUDIO_DMA_BUFFER_COUNT,
-        .dma_buf_len = FLOW3R_BSP_AUDIO_DMA_BUFFER_SIZE,
-        .use_apll = false
-    };
-    static const i2s_pin_config_t pin_config = {
-        .bck_io_num = I2S_PIN_NO_CHANGE,
-        .mck_io_num = I2S_PIN_NO_CHANGE,
-        .ws_io_num = 45,
-        .data_out_num = 46,
-        .data_in_num = I2S_PIN_NO_CHANGE,
+
+    i2s_chan_config_t chan_cfg = I2S_CHANNEL_DEFAULT_CONFIG(I2S_NUM_0, I2S_ROLE_MASTER);
+    i2s_new_channel(&chan_cfg, &tx_handle, NULL);
+
+    i2s_pdm_tx_config_t pdm_tx_cfg = {
+        .clk_cfg = I2S_PDM_TX_CLK_DAC_DEFAULT_CONFIG(FLOW3R_BSP_AUDIO_SAMPLE_RATE),
+        .slot_cfg = I2S_PDM_TX_SLOT_DAC_DEFAULT_CONFIG(I2S_DATA_BIT_WIDTH_16BIT, I2S_SLOT_MODE_STEREO),
+        .gpio_cfg = {
+            .dout = 46,
+            .dout2 = 45
+        },
     };
-    ESP_ERROR_CHECK(i2s_driver_install(0, &i2s_config, 0, NULL));
-    i2s_set_pin(0, &pin_config);
+    i2s_channel_init_pdm_tx_mode(tx_handle, &pdm_tx_cfg);
+    i2s_channel_enable(tx_handle);
 }
+
 float flow3r_bsp_audio_headphones_set_volume(bool mute, float dB) {
-    return dB; //flow3r_bsp_max98091_headphones_set_volume(mute, dB);
+    return 0; //flow3r_bsp_max98091_headphones_set_volume(mute, dB);
 }
 
 float flow3r_bsp_audio_speaker_set_volume(bool mute, float dB) {
-    return dB; //flow3r_bsp_max98091_speaker_set_volume(mute, dB);
+    return 0; //flow3r_bsp_max98091_speaker_set_volume(mute, dB);
 }
 
 int8_t flow3r_bsp_audio_headset_set_gain_dB(int8_t gain_dB) {
-    return gain_dB; //flow3r_bsp_max98091_headset_set_gain_dB(gain_dB);
+    return 0; //flow3r_bsp_max98091_headset_set_gain_dB(gain_dB);
 }
 
 void flow3r_bsp_audio_read_jacksense(flow3r_bsp_audio_jacksense_state_t *st) {