ASoC topology (formerly called dynamic firmware) allows audio DSP topology to be defined as part of the firmware package and not hard coded into the driver. This allows DSP vendors to ship multiple different firmwares or firmwares with programmable topologies for different devices (i.e. phones, tablets, TVs) using a single DSP driver. The DSP topology can be contained as part of the firmware file or exist as separate files. The topology core and file format is generic text and not tied to any single vendor or device.
The topology core consists of kernel and userspace components :-
Kernel. The kernel core reads in the topology data and builds the driver capabilities and audio topology based on this data. This includes building the DAPM graph, setting PCM and DAI capabilities, registering kcontrols and registering DAPM widgets.
The userspace tool allows the creation of binary DSP FW topology files based on a topology text files. The tool is temporarily available on github and its intended to be merged into the alsa-utils package after a clean up.
https://github.com/lgirdwood/topology.git
Changes since V2 :-
o Moved TLV channel maps into TLV UAPI header. o Report error in logs when no handler exists for vendor data types. o Fix comments on kcontrol/widget ops to match core code.
Changes since RFC :-
o Fixed patch series to survive bisection builds. o Removed widget ID enum from UAPI. o Added channel mappings to controls. o Added TLV macro patch to UAPI. o Fixed locking for runtime and init time topology loading. o Moved the UAPI group index field to the block header.
Changes since V1 (back in 2012) :-
o Name changed to ASoC Topology o Structures from soc.h and soc-dapm.h no longer exposed as UAPIs o Moved to component model from codec/platform model. o Added reserved fields in each UAPI structure. o UAPI structures packed and endianess defined for each structure. o Added support for PCM, DAI and codec <-> codec link capabilities. o Added support for client drivers manifests. o Added support for private data for each dynamic object type. o Single list of dynamic objects rather than list of each object type.
Liam