High Definition Audio (HD Audio) is a infrastructure to support high
quality audio in a PC environment which supersede AC'97. HD audio
introduce several widgets like:
1) Audio Output Converter widget
2) Audio Input Converter widget
3) Pin widget
4) Mixer widget
5) Selector widget
6) Power widget
These widget can be on the input list of other widgets. By this way,
these widget can be pipelined with each other to build a complete
audio input or output stream. Currently, audioHD driver was hard coded
to build the input and output stream to support SUN's workstations like
ultra 40 and it is not surprise the driver does not work on non sun
hardware.
A parser in audioHD driver will be implemented to search the input/output
path based on widgets layout. And the parser is expected to handle
different kinds of hardware layout by different vendors.