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      1 /*
      2  *
      3  *  BlueZ - Bluetooth protocol stack for Linux
      4  *
      5  *  Copyright (C) 2004-2009  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 
    105 #define BT_CAPABILITIES_TRANSPORT_A2DP	0
    106 #define BT_CAPABILITIES_TRANSPORT_SCO	1
    107 #define BT_CAPABILITIES_TRANSPORT_ANY	2
    108 
    109 #define BT_CAPABILITIES_ACCESS_MODE_READ	1
    110 #define BT_CAPABILITIES_ACCESS_MODE_WRITE	2
    111 #define BT_CAPABILITIES_ACCESS_MODE_READWRITE	3
    112 
    113 #define BT_FLAG_AUTOCONNECT	1
    114 
    115 struct bt_get_capabilities_req {
    116 	bt_audio_msg_header_t	h;
    117 	char			source[18];	/* Address of the local Device */
    118 	char			destination[18];/* Address of the remote Device */
    119 	char			object[128];	/* DBus object path */
    120 	uint8_t			transport;	/* Requested transport */
    121 	uint8_t			flags;		/* Requested flags */
    122 	uint8_t			seid;		/* Requested capability configuration */
    123 } __attribute__ ((packed));
    124 
    125 /**
    126  * SBC Codec parameters as per A2DP profile 1.0  4.3
    127  */
    128 
    129 /* A2DP seid are 6 bytes long so HSP/HFP are assigned to 7-8 bits */
    130 #define BT_A2DP_SEID_RANGE			(1 << 6) - 1
    131 
    132 #define BT_A2DP_SBC_SOURCE			0x00
    133 #define BT_A2DP_SBC_SINK			0x01
    134 #define BT_A2DP_MPEG12_SOURCE			0x02
    135 #define BT_A2DP_MPEG12_SINK			0x03
    136 #define BT_A2DP_MPEG24_SOURCE			0x04
    137 #define BT_A2DP_MPEG24_SINK			0x05
    138 #define BT_A2DP_ATRAC_SOURCE			0x06
    139 #define BT_A2DP_ATRAC_SINK			0x07
    140 #define BT_A2DP_UNKNOWN_SOURCE			0x08
    141 #define BT_A2DP_UNKNOWN_SINK			0x09
    142 
    143 #define BT_SBC_SAMPLING_FREQ_16000		(1 << 3)
    144 #define BT_SBC_SAMPLING_FREQ_32000		(1 << 2)
    145 #define BT_SBC_SAMPLING_FREQ_44100		(1 << 1)
    146 #define BT_SBC_SAMPLING_FREQ_48000		1
    147 
    148 #define BT_A2DP_CHANNEL_MODE_MONO		(1 << 3)
    149 #define BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL	(1 << 2)
    150 #define BT_A2DP_CHANNEL_MODE_STEREO		(1 << 1)
    151 #define BT_A2DP_CHANNEL_MODE_JOINT_STEREO	1
    152 
    153 #define BT_A2DP_BLOCK_LENGTH_4			(1 << 3)
    154 #define BT_A2DP_BLOCK_LENGTH_8			(1 << 2)
    155 #define BT_A2DP_BLOCK_LENGTH_12			(1 << 1)
    156 #define BT_A2DP_BLOCK_LENGTH_16			1
    157 
    158 #define BT_A2DP_SUBBANDS_4			(1 << 1)
    159 #define BT_A2DP_SUBBANDS_8			1
    160 
    161 #define BT_A2DP_ALLOCATION_SNR			(1 << 1)
    162 #define BT_A2DP_ALLOCATION_LOUDNESS		1
    163 
    164 #define BT_MPEG_SAMPLING_FREQ_16000		(1 << 5)
    165 #define BT_MPEG_SAMPLING_FREQ_22050		(1 << 4)
    166 #define BT_MPEG_SAMPLING_FREQ_24000		(1 << 3)
    167 #define BT_MPEG_SAMPLING_FREQ_32000		(1 << 2)
    168 #define BT_MPEG_SAMPLING_FREQ_44100		(1 << 1)
    169 #define BT_MPEG_SAMPLING_FREQ_48000		1
    170 
    171 #define BT_MPEG_LAYER_1				(1 << 2)
    172 #define BT_MPEG_LAYER_2				(1 << 1)
    173 #define BT_MPEG_LAYER_3				1
    174 
    175 #define BT_HFP_CODEC_PCM			0x00
    176 
    177 #define BT_PCM_FLAG_NREC			0x01
    178 #define BT_PCM_FLAG_PCM_ROUTING			0x02
    179 
    180 #define BT_WRITE_LOCK				(1 << 1)
    181 #define BT_READ_LOCK				1
    182 
    183 typedef struct {
    184 	uint8_t seid;
    185 	uint8_t transport;
    186 	uint8_t type;
    187 	uint8_t length;
    188 	uint8_t configured;
    189 	uint8_t lock;
    190 	uint8_t data[0];
    191 } __attribute__ ((packed)) codec_capabilities_t;
    192 
    193 typedef struct {
    194 	codec_capabilities_t capability;
    195 	uint8_t channel_mode;
    196 	uint8_t frequency;
    197 	uint8_t allocation_method;
    198 	uint8_t subbands;
    199 	uint8_t block_length;
    200 	uint8_t min_bitpool;
    201 	uint8_t max_bitpool;
    202 } __attribute__ ((packed)) sbc_capabilities_t;
    203 
    204 typedef struct {
    205 	codec_capabilities_t capability;
    206 	uint8_t channel_mode;
    207 	uint8_t crc;
    208 	uint8_t layer;
    209 	uint8_t frequency;
    210 	uint8_t mpf;
    211 	uint16_t bitrate;
    212 } __attribute__ ((packed)) mpeg_capabilities_t;
    213 
    214 typedef struct {
    215 	codec_capabilities_t capability;
    216 	uint8_t flags;
    217 	uint16_t sampling_rate;
    218 } __attribute__ ((packed)) pcm_capabilities_t;
    219 
    220 struct bt_get_capabilities_rsp {
    221 	bt_audio_msg_header_t	h;
    222 	char			source[18];	/* Address of the local Device */
    223 	char			destination[18];/* Address of the remote Device */
    224 	char			object[128];	/* DBus object path */
    225 	uint8_t			data[0];	/* First codec_capabilities_t */
    226 } __attribute__ ((packed));
    227 
    228 struct bt_open_req {
    229 	bt_audio_msg_header_t	h;
    230 	char			source[18];	/* Address of the local Device */
    231 	char			destination[18];/* Address of the remote Device */
    232 	char			object[128];	/* DBus object path */
    233 	uint8_t			seid;		/* Requested capability configuration to lock */
    234 	uint8_t			lock;		/* Requested lock */
    235 } __attribute__ ((packed));
    236 
    237 struct bt_open_rsp {
    238 	bt_audio_msg_header_t	h;
    239 	char			source[18];	/* Address of the local Device */
    240 	char			destination[18];/* Address of the remote Device */
    241 	char			object[128];	/* DBus object path */
    242 } __attribute__ ((packed));
    243 
    244 struct bt_set_configuration_req {
    245 	bt_audio_msg_header_t	h;
    246 	codec_capabilities_t	codec;		/* Requested codec */
    247 } __attribute__ ((packed));
    248 
    249 struct bt_set_configuration_rsp {
    250 	bt_audio_msg_header_t	h;
    251 	uint16_t		link_mtu;	/* Max length that transport supports */
    252 } __attribute__ ((packed));
    253 
    254 #define BT_STREAM_ACCESS_READ		0
    255 #define BT_STREAM_ACCESS_WRITE		1
    256 #define BT_STREAM_ACCESS_READWRITE	2
    257 struct bt_start_stream_req {
    258 	bt_audio_msg_header_t	h;
    259 } __attribute__ ((packed));
    260 
    261 struct bt_start_stream_rsp {
    262 	bt_audio_msg_header_t	h;
    263 } __attribute__ ((packed));
    264 
    265 /* This message is followed by one byte of data containing the stream data fd
    266    as ancilliary data */
    267 struct bt_new_stream_ind {
    268 	bt_audio_msg_header_t	h;
    269 } __attribute__ ((packed));
    270 
    271 struct bt_stop_stream_req {
    272 	bt_audio_msg_header_t	h;
    273 } __attribute__ ((packed));
    274 
    275 struct bt_stop_stream_rsp {
    276 	bt_audio_msg_header_t	h;
    277 } __attribute__ ((packed));
    278 
    279 struct bt_close_req {
    280 	bt_audio_msg_header_t	h;
    281 } __attribute__ ((packed));
    282 
    283 struct bt_close_rsp {
    284 	bt_audio_msg_header_t	h;
    285 } __attribute__ ((packed));
    286 
    287 struct bt_suspend_stream_ind {
    288 	bt_audio_msg_header_t	h;
    289 } __attribute__ ((packed));
    290 
    291 struct bt_resume_stream_ind {
    292 	bt_audio_msg_header_t	h;
    293 } __attribute__ ((packed));
    294 
    295 #define BT_CONTROL_KEY_POWER			0x40
    296 #define BT_CONTROL_KEY_VOL_UP			0x41
    297 #define BT_CONTROL_KEY_VOL_DOWN			0x42
    298 #define BT_CONTROL_KEY_MUTE			0x43
    299 #define BT_CONTROL_KEY_PLAY			0x44
    300 #define BT_CONTROL_KEY_STOP			0x45
    301 #define BT_CONTROL_KEY_PAUSE			0x46
    302 #define BT_CONTROL_KEY_RECORD			0x47
    303 #define BT_CONTROL_KEY_REWIND			0x48
    304 #define BT_CONTROL_KEY_FAST_FORWARD		0x49
    305 #define BT_CONTROL_KEY_EJECT			0x4A
    306 #define BT_CONTROL_KEY_FORWARD			0x4B
    307 #define BT_CONTROL_KEY_BACKWARD			0x4C
    308 
    309 struct bt_control_req {
    310 	bt_audio_msg_header_t	h;
    311 	uint8_t			mode;		/* Control Mode */
    312 	uint8_t			key;		/* Control Key */
    313 } __attribute__ ((packed));
    314 
    315 struct bt_control_rsp {
    316 	bt_audio_msg_header_t	h;
    317 	uint8_t			mode;		/* Control Mode */
    318 	uint8_t			key;		/* Control Key */
    319 } __attribute__ ((packed));
    320 
    321 struct bt_control_ind {
    322 	bt_audio_msg_header_t	h;
    323 	uint8_t			mode;		/* Control Mode */
    324 	uint8_t			key;		/* Control Key */
    325 } __attribute__ ((packed));
    326 
    327 /* Function declaration */
    328 
    329 /* Opens a connection to the audio service: return a socket descriptor */
    330 int bt_audio_service_open(void);
    331 
    332 /* Closes a connection to the audio service */
    333 int bt_audio_service_close(int sk);
    334 
    335 /* Receives stream data file descriptor : must be called after a
    336 BT_STREAMFD_IND message is returned */
    337 int bt_audio_service_get_data_fd(int sk);
    338 
    339 /* Human readable message type string */
    340 const char *bt_audio_strtype(uint8_t type);
    341 
    342 /* Human readable message name string */
    343 const char *bt_audio_strname(uint8_t name);
    344 
    345 #ifdef __cplusplus
    346 }
    347 #endif
    348 
    349 #endif /* BT_AUDIOCLIENT_H */
    350