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      1 /*
      2  *
      3  *  BlueZ - Bluetooth protocol stack for Linux
      4  *
      5  *  Copyright (C) 2004-2010  Marcel Holtmann <marcel (at) holtmann.org>
      6  *
      7  *  This library is free software; you can redistribute it and/or
      8  *  modify it under the terms of the GNU Lesser General Public
      9  *  License as published by the Free Software Foundation; either
     10  *  version 2.1 of the License, or (at your option) any later version.
     11  *
     12  *  This library is distributed in the hope that it will be useful,
     13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
     14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     15  *  Lesser General Public License for more details.
     16  *
     17  *  You should have received a copy of the GNU Lesser General Public
     18  *  License along with this library; if not, write to the Free Software
     19  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
     20  *
     21  */
     22 
     23 /*
     24   Message sequence chart of streaming sequence for A2DP transport
     25 
     26   Audio daemon			User
     27 				on snd_pcm_open
     28 				<--BT_GET_CAPABILITIES_REQ
     29 
     30   BT_GET_CAPABILITIES_RSP-->
     31 
     32 				on snd_pcm_hw_params
     33 				<--BT_SETCONFIGURATION_REQ
     34 
     35   BT_SET_CONFIGURATION_RSP-->
     36 
     37 				on snd_pcm_prepare
     38 				<--BT_START_STREAM_REQ
     39 
     40   <Moves to streaming state>
     41   BT_START_STREAM_RSP-->
     42 
     43   BT_NEW_STREAM_IND -->
     44 
     45 				<  streams data >
     46 				..........
     47 
     48 				on snd_pcm_drop/snd_pcm_drain
     49 
     50 				<--BT_STOP_STREAM_REQ
     51 
     52   <Moves to open state>
     53   BT_STOP_STREAM_RSP-->
     54 
     55 				on IPC close or appl crash
     56   <Moves to idle>
     57 
     58  */
     59 
     60 #ifndef BT_AUDIOCLIENT_H
     61 #define BT_AUDIOCLIENT_H
     62 
     63 #ifdef __cplusplus
     64 extern "C" {
     65 #endif
     66 
     67 #include <stdint.h>
     68 #include <stdio.h>
     69 #include <unistd.h>
     70 #include <sys/socket.h>
     71 #include <sys/un.h>
     72 #include <errno.h>
     73 
     74 #define BT_SUGGESTED_BUFFER_SIZE   512
     75 #define BT_IPC_SOCKET_NAME "\0/org/bluez/audio"
     76 
     77 /* Generic message header definition, except for RESPONSE messages */
     78 typedef struct {
     79 	uint8_t type;
     80 	uint8_t name;
     81 	uint16_t length;
     82 } __attribute__ ((packed)) bt_audio_msg_header_t;
     83 
     84 typedef struct {
     85 	bt_audio_msg_header_t h;
     86 	uint8_t posix_errno;
     87 } __attribute__ ((packed)) bt_audio_error_t;
     88 
     89 /* Message types */
     90 #define BT_REQUEST			0
     91 #define BT_RESPONSE			1
     92 #define BT_INDICATION			2
     93 #define BT_ERROR			3
     94 
     95 /* Messages names */
     96 #define BT_GET_CAPABILITIES		0
     97 #define BT_OPEN				1
     98 #define BT_SET_CONFIGURATION		2
     99 #define BT_NEW_STREAM			3
    100 #define BT_START_STREAM			4
    101 #define BT_STOP_STREAM			5
    102 #define BT_CLOSE			6
    103 #define BT_CONTROL			7
    104 #define BT_DELAY_REPORT			8
    105 
    106 #define BT_CAPABILITIES_TRANSPORT_A2DP	0
    107 #define BT_CAPABILITIES_TRANSPORT_SCO	1
    108 #define BT_CAPABILITIES_TRANSPORT_ANY	2
    109 
    110 #define BT_CAPABILITIES_ACCESS_MODE_READ	1
    111 #define BT_CAPABILITIES_ACCESS_MODE_WRITE	2
    112 #define BT_CAPABILITIES_ACCESS_MODE_READWRITE	3
    113 
    114 #define BT_FLAG_AUTOCONNECT	1
    115 
    116 struct bt_get_capabilities_req {
    117 	bt_audio_msg_header_t	h;
    118 	char			source[18];	/* Address of the local Device */
    119 	char			destination[18];/* Address of the remote Device */
    120 	char			object[128];	/* DBus object path */
    121 	uint8_t			transport;	/* Requested transport */
    122 	uint8_t			flags;		/* Requested flags */
    123 	uint8_t			seid;		/* Requested capability configuration */
    124 } __attribute__ ((packed));
    125 
    126 /**
    127  * SBC Codec parameters as per A2DP profile 1.0  4.3
    128  */
    129 
    130 /* A2DP seid are 6 bytes long so HSP/HFP are assigned to 7-8 bits */
    131 #define BT_A2DP_SEID_RANGE			(1 << 6) - 1
    132 
    133 #define BT_A2DP_SBC_SOURCE			0x00
    134 #define BT_A2DP_SBC_SINK			0x01
    135 #define BT_A2DP_MPEG12_SOURCE			0x02
    136 #define BT_A2DP_MPEG12_SINK			0x03
    137 #define BT_A2DP_MPEG24_SOURCE			0x04
    138 #define BT_A2DP_MPEG24_SINK			0x05
    139 #define BT_A2DP_ATRAC_SOURCE			0x06
    140 #define BT_A2DP_ATRAC_SINK			0x07
    141 #define BT_A2DP_UNKNOWN_SOURCE			0x08
    142 #define BT_A2DP_UNKNOWN_SINK			0x09
    143 
    144 #define BT_SBC_SAMPLING_FREQ_16000		(1 << 3)
    145 #define BT_SBC_SAMPLING_FREQ_32000		(1 << 2)
    146 #define BT_SBC_SAMPLING_FREQ_44100		(1 << 1)
    147 #define BT_SBC_SAMPLING_FREQ_48000		1
    148 
    149 #define BT_A2DP_CHANNEL_MODE_MONO		(1 << 3)
    150 #define BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL	(1 << 2)
    151 #define BT_A2DP_CHANNEL_MODE_STEREO		(1 << 1)
    152 #define BT_A2DP_CHANNEL_MODE_JOINT_STEREO	1
    153 
    154 #define BT_A2DP_BLOCK_LENGTH_4			(1 << 3)
    155 #define BT_A2DP_BLOCK_LENGTH_8			(1 << 2)
    156 #define BT_A2DP_BLOCK_LENGTH_12			(1 << 1)
    157 #define BT_A2DP_BLOCK_LENGTH_16			1
    158 
    159 #define BT_A2DP_SUBBANDS_4			(1 << 1)
    160 #define BT_A2DP_SUBBANDS_8			1
    161 
    162 #define BT_A2DP_ALLOCATION_SNR			(1 << 1)
    163 #define BT_A2DP_ALLOCATION_LOUDNESS		1
    164 
    165 #define BT_MPEG_SAMPLING_FREQ_16000		(1 << 5)
    166 #define BT_MPEG_SAMPLING_FREQ_22050		(1 << 4)
    167 #define BT_MPEG_SAMPLING_FREQ_24000		(1 << 3)
    168 #define BT_MPEG_SAMPLING_FREQ_32000		(1 << 2)
    169 #define BT_MPEG_SAMPLING_FREQ_44100		(1 << 1)
    170 #define BT_MPEG_SAMPLING_FREQ_48000		1
    171 
    172 #define BT_MPEG_LAYER_1				(1 << 2)
    173 #define BT_MPEG_LAYER_2				(1 << 1)
    174 #define BT_MPEG_LAYER_3				1
    175 
    176 #define BT_HFP_CODEC_PCM			0x00
    177 
    178 #define BT_PCM_FLAG_NREC			0x01
    179 #define BT_PCM_FLAG_PCM_ROUTING			0x02
    180 
    181 #define BT_WRITE_LOCK				(1 << 1)
    182 #define BT_READ_LOCK				1
    183 
    184 typedef struct {
    185 	uint8_t seid;
    186 	uint8_t transport;
    187 	uint8_t type;
    188 	uint8_t length;
    189 	uint8_t configured;
    190 	uint8_t lock;
    191 	uint8_t data[0];
    192 } __attribute__ ((packed)) codec_capabilities_t;
    193 
    194 typedef struct {
    195 	codec_capabilities_t capability;
    196 	uint8_t channel_mode;
    197 	uint8_t frequency;
    198 	uint8_t allocation_method;
    199 	uint8_t subbands;
    200 	uint8_t block_length;
    201 	uint8_t min_bitpool;
    202 	uint8_t max_bitpool;
    203 } __attribute__ ((packed)) sbc_capabilities_t;
    204 
    205 typedef struct {
    206 	codec_capabilities_t capability;
    207 	uint8_t channel_mode;
    208 	uint8_t crc;
    209 	uint8_t layer;
    210 	uint8_t frequency;
    211 	uint8_t mpf;
    212 	uint16_t bitrate;
    213 } __attribute__ ((packed)) mpeg_capabilities_t;
    214 
    215 typedef struct {
    216 	codec_capabilities_t capability;
    217 	uint8_t flags;
    218 	uint16_t sampling_rate;
    219 } __attribute__ ((packed)) pcm_capabilities_t;
    220 
    221 struct bt_get_capabilities_rsp {
    222 	bt_audio_msg_header_t	h;
    223 	char			source[18];	/* Address of the local Device */
    224 	char			destination[18];/* Address of the remote Device */
    225 	char			object[128];	/* DBus object path */
    226 	uint8_t			data[0];	/* First codec_capabilities_t */
    227 } __attribute__ ((packed));
    228 
    229 struct bt_open_req {
    230 	bt_audio_msg_header_t	h;
    231 	char			source[18];	/* Address of the local Device */
    232 	char			destination[18];/* Address of the remote Device */
    233 	char			object[128];	/* DBus object path */
    234 	uint8_t			seid;		/* Requested capability configuration to lock */
    235 	uint8_t			lock;		/* Requested lock */
    236 } __attribute__ ((packed));
    237 
    238 struct bt_open_rsp {
    239 	bt_audio_msg_header_t	h;
    240 	char			source[18];	/* Address of the local Device */
    241 	char			destination[18];/* Address of the remote Device */
    242 	char			object[128];	/* DBus object path */
    243 } __attribute__ ((packed));
    244 
    245 struct bt_set_configuration_req {
    246 	bt_audio_msg_header_t	h;
    247 	codec_capabilities_t	codec;		/* Requested codec */
    248 } __attribute__ ((packed));
    249 
    250 struct bt_set_configuration_rsp {
    251 	bt_audio_msg_header_t	h;
    252 	uint16_t		link_mtu;	/* Max length that transport supports */
    253 } __attribute__ ((packed));
    254 
    255 #define BT_STREAM_ACCESS_READ		0
    256 #define BT_STREAM_ACCESS_WRITE		1
    257 #define BT_STREAM_ACCESS_READWRITE	2
    258 struct bt_start_stream_req {
    259 	bt_audio_msg_header_t	h;
    260 } __attribute__ ((packed));
    261 
    262 struct bt_start_stream_rsp {
    263 	bt_audio_msg_header_t	h;
    264 } __attribute__ ((packed));
    265 
    266 /* This message is followed by one byte of data containing the stream data fd
    267    as ancilliary data */
    268 struct bt_new_stream_ind {
    269 	bt_audio_msg_header_t	h;
    270 } __attribute__ ((packed));
    271 
    272 struct bt_stop_stream_req {
    273 	bt_audio_msg_header_t	h;
    274 } __attribute__ ((packed));
    275 
    276 struct bt_stop_stream_rsp {
    277 	bt_audio_msg_header_t	h;
    278 } __attribute__ ((packed));
    279 
    280 struct bt_close_req {
    281 	bt_audio_msg_header_t	h;
    282 } __attribute__ ((packed));
    283 
    284 struct bt_close_rsp {
    285 	bt_audio_msg_header_t	h;
    286 } __attribute__ ((packed));
    287 
    288 struct bt_suspend_stream_ind {
    289 	bt_audio_msg_header_t	h;
    290 } __attribute__ ((packed));
    291 
    292 struct bt_resume_stream_ind {
    293 	bt_audio_msg_header_t	h;
    294 } __attribute__ ((packed));
    295 
    296 #define BT_CONTROL_KEY_POWER			0x40
    297 #define BT_CONTROL_KEY_VOL_UP			0x41
    298 #define BT_CONTROL_KEY_VOL_DOWN			0x42
    299 #define BT_CONTROL_KEY_MUTE			0x43
    300 #define BT_CONTROL_KEY_PLAY			0x44
    301 #define BT_CONTROL_KEY_STOP			0x45
    302 #define BT_CONTROL_KEY_PAUSE			0x46
    303 #define BT_CONTROL_KEY_RECORD			0x47
    304 #define BT_CONTROL_KEY_REWIND			0x48
    305 #define BT_CONTROL_KEY_FAST_FORWARD		0x49
    306 #define BT_CONTROL_KEY_EJECT			0x4A
    307 #define BT_CONTROL_KEY_FORWARD			0x4B
    308 #define BT_CONTROL_KEY_BACKWARD			0x4C
    309 
    310 struct bt_control_req {
    311 	bt_audio_msg_header_t	h;
    312 	uint8_t			mode;		/* Control Mode */
    313 	uint8_t			key;		/* Control Key */
    314 } __attribute__ ((packed));
    315 
    316 struct bt_control_rsp {
    317 	bt_audio_msg_header_t	h;
    318 	uint8_t			mode;		/* Control Mode */
    319 	uint8_t			key;		/* Control Key */
    320 } __attribute__ ((packed));
    321 
    322 struct bt_control_ind {
    323 	bt_audio_msg_header_t	h;
    324 	uint8_t			mode;		/* Control Mode */
    325 	uint8_t			key;		/* Control Key */
    326 } __attribute__ ((packed));
    327 
    328 struct bt_delay_report_req {
    329 	bt_audio_msg_header_t	h;
    330 	uint16_t		delay;
    331 } __attribute__ ((packed));
    332 
    333 struct bt_delay_report_ind {
    334 	bt_audio_msg_header_t	h;
    335 	uint16_t		delay;
    336 } __attribute__ ((packed));
    337 
    338 /* Function declaration */
    339 
    340 /* Opens a connection to the audio service: return a socket descriptor */
    341 int bt_audio_service_open(void);
    342 
    343 /* Closes a connection to the audio service */
    344 int bt_audio_service_close(int sk);
    345 
    346 /* Receives stream data file descriptor : must be called after a
    347 BT_STREAMFD_IND message is returned */
    348 int bt_audio_service_get_data_fd(int sk);
    349 
    350 /* Human readable message type string */
    351 const char *bt_audio_strtype(uint8_t type);
    352 
    353 /* Human readable message name string */
    354 const char *bt_audio_strname(uint8_t name);
    355 
    356 #ifdef __cplusplus
    357 }
    358 #endif
    359 
    360 #endif /* BT_AUDIOCLIENT_H */
    361