Continue to tweak AirPlay to SPDIF (still drifting)

components/squeezelite/decode_external.c

@@ -61,8 +61,9 @@ static void sink_data_handler(const uint8_t *data, uint32_t len)
 	// there will always be room at some point
 	while (len) {
 		LOCK_O;
-		
-		bytes = min(len, _buf_cont_write(outputbuf));
+
+		bytes = min(_buf_space(outputbuf), _buf_cont_write(outputbuf));
+		bytes = min(len, bytes);
 #if BYTES_PER_FRAME == 4
 		memcpy(outputbuf->writep, data, bytes);
 #else
@@ -127,7 +128,7 @@ static void bt_sink_cmd_handler(bt_sink_cmd_t cmd, ...)
 		LOG_INFO("BT sink stopped");
 		break;
 	case BT_SINK_RATE:
-		output.next_sample_rate = va_arg(args, u32_t);
+		output.next_sample_rate = output.current_sample_rate = va_arg(args, u32_t);
 		LOG_INFO("Setting BT sample rate %u", output.next_sample_rate);
 		break;
 	case BT_SINK_VOLUME: {
@@ -151,7 +152,7 @@ static void raop_sink_data_handler(const uint8_t *data, uint32_t len, u32_t play
 	
 	raop_sync.playtime = playtime;
 	raop_sync.len = len;
-	
+
 	sink_data_handler(data, len);
 }	
 
@@ -186,7 +187,7 @@ void raop_sink_cmd_handler(raop_event_t event, void *param)
 				LOG_INFO("backend played %u, desired %u, (delta:%d)", ms, now - raop_sync.start_time, error);
 				if (abs(error) < 10 && abs(raop_sync.error) < 10) raop_sync.start = false;
 			} else {	
-				// in how many ms will the most recent block play (there is one extra block of FRAME_BLOCK == MAX_SILENCE_FRAMES which is not in queue and not in outputbuf)
+				// in how many ms will the most recent block play 
 				ms = ((u64_t) ((_buf_used(outputbuf) - raop_sync.len) / BYTES_PER_FRAME + output.device_frames + output.frames_in_process) * 1000) / RAOP_SAMPLE_RATE - (now - output.updated);
 				error = (raop_sync.playtime - now) - ms;
 				LOG_INFO("head local:%u, remote:%u (delta:%d)", ms, raop_sync.playtime - now, error);
@@ -219,7 +220,7 @@ void raop_sink_cmd_handler(raop_event_t event, void *param)
 			raop_sync.start = true;		
 			raop_sync.enabled = !strcasestr(output.device, "BT");
 			output.external = true;
-			output.next_sample_rate = RAOP_SAMPLE_RATE;
+			output.next_sample_rate = output.current_sample_rate = RAOP_SAMPLE_RATE;
 			output.state = OUTPUT_STOPPED;
 			break;
 		case RAOP_STOP:

components/squeezelite/output_i2s.c

@@ -84,7 +84,7 @@ sure that using rate_delay would fix that
 
 typedef enum { DAC_ON = 0, DAC_OFF, DAC_POWERDOWN, DAC_VOLUME } dac_cmd_e;
 
-// must have an integer ratio with FRAME_BLOCK
+// must have an integer ratio with FRAME_BLOCK (see spdif comment)
 #define DMA_BUF_LEN		512	
 #define DMA_BUF_COUNT	12
 
@@ -116,6 +116,7 @@ static int bytes_per_frame;
 static thread_type thread, stats_thread;
 static u8_t *obuf;
 static bool spdif;
+static size_t dma_buf_frames;
 
 DECLARE_ALL_MIN_MAX;
 
@@ -268,27 +269,37 @@ void output_init_i2s(log_level level, char *device, unsigned output_buf_size, ch
 									};
 		i2s_config.sample_rate = output.current_sample_rate * 2;
 		i2s_config.bits_per_sample = 32;
+		// Normally counted in frames, but 16 sample are transformed into 32 bits in spdif
+		i2s_config.dma_buf_len = DMA_BUF_LEN / 2;	
+		i2s_config.dma_buf_count = DMA_BUF_COUNT * 2;
+		/* 
+		   In DMA, we have room for (LEN * COUNT) frames of 32 bits samples that 
+		   we push at sample_rate * 2. Each of these peuso-frames is a single true
+		   audio frame. So the real depth is true frames is (LEN * COUNT / 2)
+		*/   
+		dma_buf_frames = DMA_BUF_COUNT * DMA_BUF_LEN / 2;	
 	} else {
 		pin_config = (i2s_pin_config_t) { .bck_io_num = CONFIG_I2S_BCK_IO, .ws_io_num = CONFIG_I2S_WS_IO, 
 										.data_out_num = CONFIG_I2S_DO_IO, .data_in_num = -1 //Not used
 									};
 		i2s_config.sample_rate = output.current_sample_rate;
 		i2s_config.bits_per_sample = bytes_per_frame * 8 / 2;
+		// Counted in frames (but i2s allocates a buffer <= 4092 bytes)
+		i2s_config.dma_buf_len = DMA_BUF_LEN;	
+		i2s_config.dma_buf_count = DMA_BUF_COUNT;
+		dma_buf_frames = DMA_BUF_COUNT * DMA_BUF_LEN;	
 #ifdef TAS575x	
 		gpio_pad_select_gpio(CONFIG_SPDIF_DO_IO);
 		gpio_set_direction(CONFIG_SPDIF_DO_IO, GPIO_MODE_OUTPUT);
 		gpio_set_level(CONFIG_SPDIF_DO_IO, 0);
 #endif			
 	}
-	
+
 	i2s_config.mode = I2S_MODE_MASTER | I2S_MODE_TX;
 	i2s_config.channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT;
 	i2s_config.communication_format = I2S_COMM_FORMAT_I2S| I2S_COMM_FORMAT_I2S_MSB;
 	// in case of overflow, do not replay old buffer
 	i2s_config.tx_desc_auto_clear = true;		
-	i2s_config.dma_buf_count = DMA_BUF_COUNT;
-	// Counted in frames (but i2s allocates a buffer <= 4092 bytes)
-	i2s_config.dma_buf_len = DMA_BUF_LEN;
 	i2s_config.use_apll = true;
 	i2s_config.intr_alloc_flags = ESP_INTR_FLAG_LEVEL1; //Interrupt level 1
 
@@ -391,7 +402,6 @@ static int _i2s_write_frames(frames_t out_frames, bool silence, s32_t gainL, s32
 	return out_frames;
 }
 
-
 /****************************************************************************************
  * Main output thread
  */
@@ -415,7 +425,7 @@ static void *output_thread_i2s() {
 		TIME_MEASUREMENT_START(timer_start);
 		
 		LOCK;
-		
+				
 		// manage led display
 		if (state != output.state) {
 			LOG_INFO("Output state is %d", output.state);
@@ -441,11 +451,11 @@ static void *output_thread_i2s() {
 		
 		output.updated = gettime_ms();
 		output.frames_played_dmp = output.frames_played;
-		// try to estimate how much we have consumed from the DMA buffer
-		output.device_frames = DMA_BUF_COUNT * DMA_BUF_LEN - ((output.updated - fullness) * output.current_sample_rate) / 1000;
+		// try to estimate how much we have consumed from the DMA buffer (calculation is incorrect at the very beginning ...)
+		output.device_frames = dma_buf_frames - ((output.updated - fullness) * output.current_sample_rate) / 1000;
 		oframes = _output_frames( iframes );
 		output.frames_in_process = oframes;
-				
+								
 		SET_MIN_MAX_SIZED(oframes,rec,iframes);
 		SET_MIN_MAX_SIZED(_buf_used(outputbuf),o,outputbuf->size);
 		SET_MIN_MAX_SIZED(_buf_used(streambuf),s,streambuf->size);
@@ -547,6 +557,11 @@ static void *output_thread_i2s_stats() {
 			LOG_INFO("              ----------+----------+-----------+-----------+");
 			RESET_ALL_MIN_MAX;
 		}
+		LOG_INFO("Heap internal:%zu (min:%zu) external:%zu (min:%zu)", 
+					heap_caps_get_free_size(MALLOC_CAP_INTERNAL),
+					heap_caps_get_minimum_free_size(MALLOC_CAP_INTERNAL),
+					heap_caps_get_free_size(MALLOC_CAP_SPIRAM),
+					heap_caps_get_minimum_free_size(MALLOC_CAP_SPIRAM));
 		usleep(STATS_PERIOD_MS *1000);
 	}
 	return NULL;