Merge "Compute the audio data buffer size based on stream characteristics" (07c99f2a) · Commits · e / os / android_packages_modules_Bluetooth

system/audio_a2dp_hw/audio_a2dp_hw.cc

+114 −4

Original line number	Diff line number	Diff line
		@@ -150,6 +150,10 @@ struct a2dp_stream_in {
		*****************************************************************************/

		static size_t out_get_buffer_size(const struct audio_stream* stream);
		static size_t audio_stream_compute_buffer_size(
		btav_a2dp_codec_sample_rate_t codec_sample_rate,
		btav_a2dp_codec_bits_per_sample_t codec_bits_per_sample,
		btav_a2dp_codec_channel_mode_t codec_channel_mode);

		/*****************************************************************************
		* Externs
		@@ -607,6 +611,9 @@ static int a2dp_read_output_audio_config(
		common->cfg.rate = stream_config.rate;
		common->cfg.channel_mask = stream_config.channel_mask;
		common->cfg.format = stream_config.format;
		common->buffer_sz = audio_stream_compute_buffer_size(
		codec_config->sample_rate, codec_config->bits_per_sample,
		codec_config->channel_mode);
		}

		INFO(
		@@ -712,8 +719,8 @@ static void a2dp_open_ctrl_path(struct a2dp_stream_common* common) {
		/* retry logic to catch any timing variations on control channel */
		for (i = 0; i < CTRL_CHAN_RETRY_COUNT; i++) {
		/* connect control channel if not already connected */
		if ((common->ctrl_fd = skt_connect(A2DP_CTRL_PATH, common->buffer_sz)) >
		0) {
		if ((common->ctrl_fd = skt_connect(
		A2DP_CTRL_PATH, AUDIO_STREAM_CONTROL_OUTPUT_BUFFER_SZ)) > 0) {
		/* success, now check if stack is ready */
		if (check_a2dp_ready(common) == 0) break;

		@@ -927,6 +934,106 @@ static size_t out_get_buffer_size(const struct audio_stream* stream) {
		return period_size;
		}

		static size_t audio_stream_compute_buffer_size(
		btav_a2dp_codec_sample_rate_t codec_sample_rate,
		btav_a2dp_codec_bits_per_sample_t codec_bits_per_sample,
		btav_a2dp_codec_channel_mode_t codec_channel_mode) {
		size_t buffer_sz = AUDIO_STREAM_OUTPUT_BUFFER_SZ; // Default value
		const uint32_t time_period_ms = 20; // Conservative 20ms
		uint32_t sample_rate;
		uint32_t bits_per_sample;
		uint32_t number_of_channels;

		// Check the codec config sample rate
		switch (codec_sample_rate) {
		case BTAV_A2DP_CODEC_SAMPLE_RATE_44100:
		sample_rate = 44100;
		break;
		case BTAV_A2DP_CODEC_SAMPLE_RATE_48000:
		sample_rate = 48000;
		break;
		case BTAV_A2DP_CODEC_SAMPLE_RATE_88200:
		sample_rate = 88200;
		break;
		case BTAV_A2DP_CODEC_SAMPLE_RATE_96000:
		sample_rate = 96000;
		break;
		case BTAV_A2DP_CODEC_SAMPLE_RATE_176400:
		sample_rate = 176400;
		break;
		case BTAV_A2DP_CODEC_SAMPLE_RATE_192000:
		sample_rate = 192000;
		break;
		case BTAV_A2DP_CODEC_SAMPLE_RATE_NONE:
		default:
		ERROR("Invalid sample rate: 0x%x", codec_sample_rate);
		return buffer_sz;
		}

		// Check the codec config bits per sample
		switch (codec_bits_per_sample) {
		case BTAV_A2DP_CODEC_BITS_PER_SAMPLE_16:
		bits_per_sample = 16;
		break;
		case BTAV_A2DP_CODEC_BITS_PER_SAMPLE_24:
		bits_per_sample = 24;
		break;
		case BTAV_A2DP_CODEC_BITS_PER_SAMPLE_32:
		bits_per_sample = 32;
		break;
		case BTAV_A2DP_CODEC_BITS_PER_SAMPLE_NONE:
		default:
		ERROR("Invalid bits per sample: 0x%x", codec_bits_per_sample);
		return buffer_sz;
		}

		// Check the codec config channel mode
		switch (codec_channel_mode) {
		case BTAV_A2DP_CODEC_CHANNEL_MODE_MONO:
		number_of_channels = 1;
		break;
		case BTAV_A2DP_CODEC_CHANNEL_MODE_STEREO:
		number_of_channels = 2;
		break;
		case BTAV_A2DP_CODEC_CHANNEL_MODE_NONE:
		default:
		ERROR("Invalid channel mode: 0x%x", codec_channel_mode);
		return buffer_sz;
		}

		//
		// The buffer size is computed by using the following formula:
		//
		// AUDIO_STREAM_OUTPUT_BUFFER_SIZE =
		// (TIME_PERIOD_MS * AUDIO_STREAM_OUTPUT_BUFFER_PERIODS *
		// SAMPLE_RATE_HZ * NUMBER_OF_CHANNELS * (BITS_PER_SAMPLE / 8)) / 1000
		//
		// AUDIO_STREAM_OUTPUT_BUFFER_PERIODS controls how the socket buffer is
		// divided for AudioFlinger data delivery. The AudioFlinger mixer delivers
		// data in chunks of
		// (AUDIO_STREAM_OUTPUT_BUFFER_SIZE / AUDIO_STREAM_OUTPUT_BUFFER_PERIODS) .
		// If the number of periods is 2, the socket buffer represents "double
		// buffering" of the AudioFlinger mixer buffer.
		//
		// Furthermore, the AudioFlinger expects the buffer size to be a multiple
		// of 16 frames.
		const size_t divisor = (AUDIO_STREAM_OUTPUT_BUFFER_PERIODS * 16 *
		number_of_channels * bits_per_sample) /
		8;

		buffer_sz = (time_period_ms * AUDIO_STREAM_OUTPUT_BUFFER_PERIODS *
		sample_rate * number_of_channels * (bits_per_sample / 8)) /
		1000;

		// Adjust the buffer size so it can be divided by the divisor
		const size_t remainder = buffer_sz % divisor;
		if (remainder != 0) {
		buffer_sz += divisor - remainder;
		}

		return buffer_sz;
		}

		static uint32_t out_get_channels(const struct audio_stream* stream) {
		struct a2dp_stream_out* out = (struct a2dp_stream_out*)stream;

		@@ -1434,8 +1541,11 @@ static int adev_open_output_stream(struct audio_hw_device* dev,
		config->channel_mask =
		out_get_channels((const struct audio_stream*)&out->stream);

		INFO("Output stream config: format=0x%x sample_rate=%d channel_mask=0x%x",
		config->format, config->sample_rate, config->channel_mask);
		INFO(
		"Output stream config: format=0x%x sample_rate=%d channel_mask=0x%x "
		"buffer_sz=%zu",
		config->format, config->sample_rate, config->channel_mask,
		out->common.buffer_sz);
		}
		*stream_out = &out->stream;
		a2dp_dev->output = out;

system/audio_a2dp_hw/audio_a2dp_hw.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -54,6 +54,7 @@
		// resulting in mixer sleep and throttling. We increase this to 28 * 512 to help
		// reduce the effect of variable data consumption.
		#define AUDIO_STREAM_OUTPUT_BUFFER_SZ (28 * 512)
		#define AUDIO_STREAM_CONTROL_OUTPUT_BUFFER_SZ 256

		// AUDIO_STREAM_OUTPUT_BUFFER_PERIODS controls how the socket buffer is divided
		// for AudioFlinger data delivery. The AudioFlinger mixer delivers data in

system/udrv/ulinux/uipc_linux.h

deleted100644 → 0

+0 −34

Original line number	Diff line number	Diff line
		/******************************************************************************
		*
		* Copyright (C) 2007-2012 Broadcom Corporation
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at:
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*
		******************************************************************************/
		#ifndef _UIPC_LINUX_H_
		#define _UIPC_LINUX_H_

		typedef int SOCKET;
		#define INVALID_SOCKET (SOCKET)(-1)
		#define SOCKET_ERROR (-1)

		/* tcp/ip socket configuration */
		typedef struct {
		char* p_address;
		unsigned int port;
		} tUIPC_LINUX_CFG_TCP;

		/* Socket configuration for GLGPS interface */
		extern tUIPC_LINUX_CFG_TCP uipc_linux_cfg_glgps;

		#endif /* _UIPC_LINUX_H_ */