| # Composite audio driver |
| |
| The `Composite` interface is a FIDL protocol exposed by audio drivers. The `Composite` interface |
| is generic and allows the configuration of various audio hardware types including those supported |
| by the `StreamConfig`, `Dai` and `Codec` FIDL interfaces. The `Composite` interface is more |
| generic and provides more flexible routing within audio subsystems. |
| |
| In this protocol, ring buffer and DAI endpoints are configured based on the topology exposed via |
| the [Audio Signal Processing](signal-processing.md) APIs. In particular, endpoints represent the |
| hardware that is abstracted, specifically the number of ring buffers and DAI interconnects. Audio |
| hardware that can be represented by other audio driver types (`StreamConfig`, `Dai`, `Codec`) can |
| instead be represented with a `Composite` driver. For example, a `Composite` driver can represent |
| a `Codec` with a topology that has zero RingBuffer endpoints and one DAI interconnect endpoint. |
| |
| When an audio driver provides the `Composite` interface, its client is responsible for configuring |
| the hardware, including data topology. Driver responsibilities include using the |
| `SignalProcessing` protocol to enumerate the topologies and capabilities supported by the hardware |
| it abstracts. |
| |
| The `Composite` FIDL protocol is defined at |
| [composite.fidl](/sdk/fidl/fuchsia.hardware.audio/composite.fidl). |
| |
| |
