Controller integrated audio codec for advanced audio distribution profile audio streaming applications
A novel and useful apparatus for and method of integrating the advanced audio distribution profile (A2DP) audio codec into a Bluetooth controller for audio streaming applications. The mechanism functions to break the prior art Bluetooth protocol stack by integrating a profile packet composer into the controller. The profile/stack control signaling is performed by the host while the profile data packet composer is implemented in the controller. The integrated data packet composer does not break the data path and flow control over the standard HCI. Further, the integrated packet composer allows the controller to open a dedicated data interface for specific applications (e.g., PCM/I2S for audio data).
1. A method of encoding streaming audio in a Bluetooth controller coupled to a communications channel, said method comprising the steps of:
receiving audio streaming data from a host system utilizing a host control application programming interface (API);
encoding said audio streaming data to generate encoded audio data therefrom; and
assembling transmit packets incorporating said encoded audio data for transmission over said communications channel, wherein said communications channel comprises a Bluetooth wireless link,
wherein said transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets; and
wherein said host control API comprises a multiple sink configuration command operative to configure a plurality of advanced audio distribution profile (A2DP) transport channels in said Bluetooth controller.
2. The method according to claim 1 , wherein said audio streaming data comprises pulse code modulated (PCM) data.
3. The method according to claim 1 , wherein said step of encoding comprises encoding pulse code modulated (PCM) input data to subband codec (SBC) format.
4. The method according to claim 1 , wherein data path processing is performed by said controller while control functions and associated signaling channel are performed by said host system.
5. A method of encoding streaming audio in a Bluetooth controller, said method comprising the steps of:
receiving pulse code modulated (PCM) format audio streaming data from a host system utilizing a host control application programming interface (API);
encoding said PCM audio streaming data to subband codec (SBC) format; and
generating transmit packets incorporating said SBC encoded audio data for transmission over a Bluetooth link,
wherein said host control API comprises a multiple sink configuration command operative to configure a plurality of advanced audio distribution profile (A2DP) transport channels in said Bluetooth controller.
6. The method according to claim 5 , wherein data path processing is performed by said Bluetooth controller while control functions and associated signaling channel are performed by said host system.
7. The method according to claim 5 , wherein said transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.
8. The method according to claim 5 , wherein said host control API enables said host system to control and configure said Bluetooth controller.
9. The method according to claim 5 , wherein said host control API comprises an open stream command operative to establish an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.
10. The method according to claim 5 , wherein said host control API comprises a close stream command operative to close an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.
11. The method according to claim 5 , wherein said host control API comprises a codec configuration command operative to configure an SBC codec within said Bluetooth controller.
12. The method according to claim 5 , wherein said host control API comprises a start stream command operative to start SBC data streaming to a remote Bluetooth device.
13. The method according to claim 5 , wherein said host control API comprises a stop stream command operative to stop SBC streaming to a remote Bluetooth device.
14. A single chip Bluetooth controller, comprising:
a Bluetooth radio for establishing a link to a remote device;
a host control application programming interface (API) defining a plurality of commands for controlling and configuring said Bluetooth controller;
a host interface operative to receive a pulse code modulated (PCM) format input audio data stream from a host system utilizing said host control API;
an audio encoder operative to encode said audio data stream into subband codec (SBC) format; and
a profile data packet composer operative to encapsulate said SBC formatted audio data stream to generate Bluetooth transmit packets therefrom for transmission by said Bluetooth radio over said link to said remote device,
wherein said host control API comprises a multiple sink configuration command operative to configure a plurality of advanced audio distribution profile (A2DP) transport channels in said Bluetooth controller.
15. The controller according to claim 14 , wherein said host control API comprises an open stream command operative to establish an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.
16. The controller according to claim 14 , wherein said host control API comprises a close stream command operative to close an advanced audio distribution profile (A2DP) transport channel in said Bluetooth controller.
17. The controller according to claim 14 , wherein said host control API comprises a codec configuration command operative to configure an SBC codec within said Bluetooth controller.
18. The controller according to claim 14 , wherein said host control API comprises a start stream command operative to start SBC data streaming to a remote Bluetooth device.
19. The controller according to claim 14 , wherein said host control API comprises a stop stream command operative to stop SBC streaming to a remote Bluetooth device.
20. The controller according to claim 14 , wherein said Bluetooth transmit packets comprise Audio/Video Distribution Transport Protocol (AVDTP) packets.