- uint8_t ControlSize; /**< Size of each element in the ChanelControlls array */\r
- uint8_t ChannelControls[3]; /**< Feature masks for the control channel, and each separate audio channel */\r
- \r
- uint8_t FeatureUnitStrIndex; /**< Index of a string descriptor describing this descriptor within the device */\r
- } USB_AudioFeatureUnit_t;\r
-\r
- /** Type define for an Audio class specific input terminal descriptor. This indicates to the host that the device\r
- * contains an input audio source, either from a physical terminal on the device, or a logical terminal (for example,\r
- * a USB endpoint). See the USB Audio specification for more details.\r
- */\r
- typedef struct\r
- {\r
- USB_Descriptor_Header_t Header; /**< Regular descriptor header containing the descriptor's type and length */\r
- uint8_t Subtype; /**< Sub type value used to distinguish between audio class specific descriptors */\r
- \r
- uint8_t TerminalID; /**< ID value of this terminal unit - must be a unique value within the device */\r
- uint16_t TerminalType; /**< Type of terminal, a TERMINAL_* mask */\r
- uint8_t AssociatedOutputTerminal; /**< ID of associated output terminal, for physically grouped terminals\r
- * such as the speaker and microphone of a phone handset\r
- */\r
- uint8_t TotalChannels; /**< Total number of separate audio channels within this interface (right, left, etc.) */\r
- uint16_t ChannelConfig; /**< CHANNEL_* masks indicating what channel layout is supported by this terminal */\r
- \r
- uint8_t ChannelStrIndex; /**< Index of a string descriptor describing this channel within the device */\r
- uint8_t TerminalStrIndex; /**< Index of a string descriptor describing this descriptor within the device */\r
- } USB_AudioInputTerminal_t;\r
-\r
- /** Type define for an Audio class specific output terminal descriptor. This indicates to the host that the device\r
- * contains an output audio sink, either to a physical terminal on the device, or a logical terminal (for example,\r
- * a USB endpoint). See the USB Audio specification for more details.\r
- */\r
- typedef struct\r
- {\r
- USB_Descriptor_Header_t Header; /**< Regular descriptor header containing the descriptor's type and length */\r
- uint8_t Subtype; /**< Sub type value used to distinguish between audio class specific descriptors */\r
- \r
- uint8_t TerminalID; /**< ID value of this terminal unit - must be a unique value within the device */\r
- uint16_t TerminalType; /**< Type of terminal, a TERMINAL_* mask */\r
- uint8_t AssociatedInputTerminal; /**< ID of associated input terminal, for physically grouped terminals\r
- * such as the speaker and microphone of a phone handset\r
- */\r
- uint8_t SourceID; /**< ID value of the unit this terminal's audio is sourced from */\r
- \r
- uint8_t TerminalStrIndex; /**< Index of a string descriptor describing this descriptor within the device */\r
- } USB_AudioOutputTerminal_t;\r
- \r
- /** Type define for an Audio class specific streaming interface descriptor. This indicates to the host\r
- * how audio streams within the device are formatted. See the USB Audio specification for more details.\r
- */\r
- typedef struct\r
- {\r
- USB_Descriptor_Header_t Header; /**< Regular descriptor header containing the descriptor's type and length */\r
- uint8_t Subtype; /**< Sub type value used to distinguish between audio class specific descriptors */\r
- \r
- uint8_t TerminalLink; /**< ID value of the output terminal this descriptor is describing */\r
- \r
- uint8_t FrameDelay; /**< Delay in frames resulting from the complete sample processing from input to output */\r
- uint16_t AudioFormat; /**< Format of the audio stream, see Audio Device Formats specification */\r
- } USB_AudioInterface_AS_t;\r
- \r
- /** Type define for a 24bit audio sample frequency structure. GCC does not contain a built in 24bit datatype,\r
- * this this structure is used to build up the value instead. Fill this structure with the SAMPLE_FREQ() macro.\r
- */\r
- typedef struct\r
- {\r
- uint16_t LowWord; /**< Low 16 bits of the 24-bit value */\r
- uint8_t HighByte; /**< Upper 8 bits of the 24-bit value */\r
- } AudioSampleFreq_t;\r
-\r
- /** Type define for an Audio class specific audio format descriptor. This is used to give the host full details\r
- * about the number of channels, the sample resolution, acceptable sample frequencies and encoding method used\r
- * in the device's audio streams. See the USB Audio specification for more details.\r
- */\r
- typedef struct\r
- {\r
- USB_Descriptor_Header_t Header; /**< Regular descriptor header containing the descriptor's type and length */\r
- uint8_t Subtype; /**< Sub type value used to distinguish between audio class specific descriptors */\r
-\r
- uint8_t FormatType; /**< Format of the audio stream, see Audio Device Formats specification */\r
- uint8_t Channels; /**< Total number of discrete channels in the stream */\r
- \r
- uint8_t SubFrameSize; /**< Size in bytes of each channel's sample data in the stream */\r
- uint8_t BitResolution; /**< Bits of resolution of each channel's samples in the stream */\r
-\r
- uint8_t SampleFrequencyType; /**< Total number of sample frequencies supported by the device */ \r
- AudioSampleFreq_t SampleFrequencies[1]; /**< Sample frequencies supported by the device */\r
- } USB_AudioFormat_t;\r
- \r
- /** Type define for an Audio class specific endpoint descriptor. This contains a regular endpoint \r
- * descriptor with a few Audio-class specific extensions. See the USB Audio specification for more details.\r
- */\r
- typedef struct\r
- {\r
- USB_Descriptor_Endpoint_t Endpoint; /**< Standard endpoint descriptor describing the audio endpoint */\r
-\r
- uint8_t Refresh; /**< Always set to zero */\r
- uint8_t SyncEndpointNumber; /**< Endpoint address to send synchronisation information to, if needed (zero otherwise) */\r
- } USB_AudioStreamEndpoint_Std_t;\r
- \r
- /** Type define for an Audio class specific extended endpoint descriptor. This contains extra information\r
- * on the usage of endpoints used to stream audio in and out of the USB Audio device, and follows an Audio\r
- * class specific extended endpoint descriptor. See the USB Audio specification for more details.\r
- */\r
- typedef struct\r
- {\r
- USB_Descriptor_Header_t Header; /**< Regular descriptor header containing the descriptor's type and length */\r
- uint8_t Subtype; /**< Sub type value used to distinguish between audio class specific descriptors */\r
- \r
- uint8_t Attributes; /**< Audio class specific endpoint attributes, such as ACCEPTS_SMALL_PACKETS */\r
+ /** Determines if the given audio interface is ready for a sample to be read from it, and selects the streaming\r
+ * OUT endpoint ready for reading.\r
+ *\r
+ * \param[in,out] AudioInterfaceInfo Pointer to a structure containing an Audio Class configuration and state\r
+ *\r
+ * \return Boolean true if the given Audio interface has a sample to be read, false otherwise\r
+ */\r
+ bool Audio_Device_IsSampleReceived(USB_ClassInfo_Audio_Device_t* const AudioInterfaceInfo);\r
+\r
+ /** Determines if the given audio interface is ready to accept the next sample to be written to it, and selects\r
+ * the streaming IN endpoint ready for writing.\r
+ *\r
+ * \param[in,out] AudioInterfaceInfo Pointer to a structure containing an Audio Class configuration and state\r
+ *\r
+ * \return Boolean true if the given Audio interface is ready to accept the next sample, false otherwise\r
+ */\r
+ bool Audio_Device_IsReadyForNextSample(USB_ClassInfo_Audio_Device_t* const AudioInterfaceInfo);\r
+\r
+ /* Inline Functions: */\r
+ /** Reads the next 8-bit audio sample from the current audio interface.\r
+ *\r
+ * \note This should be preceded immediately by a call to the USB_Audio_IsSampleReceived() function to ensure that\r
+ * the correct endpoint is selected and ready for data.\r
+ *\r
+ * \param[in,out] AudioInterfaceInfo Pointer to a structure containing an Audio Class configuration and state\r
+ *\r
+ * \return Signed 8-bit audio sample from the audio interface\r
+ */\r
+ static inline int8_t Audio_Device_ReadSample8(USB_ClassInfo_Audio_Device_t* const AudioInterfaceInfo) ATTR_ALWAYS_INLINE;\r
+ static inline int8_t Audio_Device_ReadSample8(USB_ClassInfo_Audio_Device_t* const AudioInterfaceInfo)\r
+ {\r
+ int8_t Sample;\r
+ \r
+ (void)AudioInterfaceInfo;\r
+\r
+ Sample = Endpoint_Read_Byte();\r
+\r
+ if (!(Endpoint_BytesInEndpoint()))\r
+ Endpoint_ClearOUT();\r
+ \r
+ return Sample;\r
+ }\r