Merge "Add a workaround to play A2DP SBC Mono" (af1205d2) · Commits · e / os / android_packages_modules_Bluetooth

system/audio_a2dp_hw/src/audio_a2dp_hw.cc

+31 −2

Original line number	Diff line number	Diff line
		@@ -105,6 +105,7 @@ struct a2dp_audio_device {
		struct a2dp_config {
		uint32_t rate;
		uint32_t channel_mask;
		bool is_stereo_to_mono; // True if fetching Stereo and mixing into Mono
		int format;
		};

		@@ -591,24 +592,34 @@ static int a2dp_read_output_audio_config(
		switch (codec_config->channel_mode) {
		case BTAV_A2DP_CODEC_CHANNEL_MODE_MONO:
		stream_config.channel_mask = AUDIO_CHANNEL_OUT_MONO;
		stream_config.is_stereo_to_mono = true;
		break;
		case BTAV_A2DP_CODEC_CHANNEL_MODE_STEREO:
		stream_config.channel_mask = AUDIO_CHANNEL_OUT_STEREO;
		stream_config.is_stereo_to_mono = false;
		break;
		case BTAV_A2DP_CODEC_CHANNEL_MODE_NONE:
		default:
		ERROR("Invalid channel mode: 0x%x", codec_config->channel_mode);
		return -1;
		}
		if (stream_config.is_stereo_to_mono) {
		stream_config.channel_mask = AUDIO_CHANNEL_OUT_STEREO;
		}

		// Update the output stream configuration
		if (update_stream_config) {
		common->cfg.rate = stream_config.rate;
		common->cfg.channel_mask = stream_config.channel_mask;
		common->cfg.is_stereo_to_mono = stream_config.is_stereo_to_mono;
		common->cfg.format = stream_config.format;
		common->buffer_sz = audio_a2dp_hw_stream_compute_buffer_size(
		codec_config->sample_rate, codec_config->bits_per_sample,
		codec_config->channel_mode);
		if (common->cfg.is_stereo_to_mono) {
		// We need to fetch twice as much data from the Audio framework
		common->buffer_sz *= 2;
		}
		}

		INFO(
		@@ -679,7 +690,11 @@ static int a2dp_write_output_audio_config(struct a2dp_stream_common* common) {
		codec_config.channel_mode = BTAV_A2DP_CODEC_CHANNEL_MODE_MONO;
		break;
		case AUDIO_CHANNEL_OUT_STEREO:
		if (common->cfg.is_stereo_to_mono) {
		codec_config.channel_mode = BTAV_A2DP_CODEC_CHANNEL_MODE_MONO;
		} else {
		codec_config.channel_mode = BTAV_A2DP_CODEC_CHANNEL_MODE_STEREO;
		}
		break;
		default:
		ERROR("Invalid channel mask: 0x%x", common->cfg.channel_mask);
		@@ -844,6 +859,7 @@ static ssize_t out_write(struct audio_stream_out* stream, const void* buffer,
		size_t bytes) {
		struct a2dp_stream_out* out = (struct a2dp_stream_out*)stream;
		int sent = -1;
		size_t write_bytes = bytes;

		DEBUG("write %zu bytes (fd %d)", bytes, out->common.audio_fd);

		@@ -865,8 +881,21 @@ static ssize_t out_write(struct audio_stream_out* stream, const void* buffer,
		goto finish;
		}

		// Mix the stereo into mono if necessary
		if (out->common.cfg.is_stereo_to_mono) {
		const size_t frames = bytes / audio_stream_out_frame_size(stream);
		int16_t* src = (int16_t*)buffer;
		int16_t* dst = (int16_t*)buffer;
		for (size_t i = 0; i < frames; i++, dst++, src += 2) {
		*dst = (int16_t)(((int32_t)src[0] + (int32_t)src[1]) >> 1);
		}
		write_bytes /= 2;
		DEBUG("stereo-to-mono mixing: write %zu bytes (fd %d)", write_bytes,
		out->common.audio_fd);
		}

		lock.unlock();
		sent = skt_write(out->common.audio_fd, buffer, bytes);
		sent = skt_write(out->common.audio_fd, buffer, write_bytes);
		lock.lock();

		if (sent == -1) {