[alsa-devel] [PATCH 5/9] ALSA: usb-audio: parse clock topology of UAC2 devices

Daniel Mack daniel at caiaq.de
Mon May 31 14:51:31 CEST 2010


On Mon, May 31, 2010 at 01:35:40PM +0200, Daniel Mack wrote:
> Audio devices which comply to the UAC2 standard can export complex clock
> topologies in its descriptors and set up links between them.
> 
> The entities that are defined are
> 
>  - clock sources, which define the end-leafs.
>  - clock selectors, which act as switch to select one out of many
>    possible clocks sources.
>  - clock multipliers, which have an input clock source, and act as clock
>    source again. They can be used to derive one clock from another.
> 
> All sample rate changes, clock validity queries and the like must go to
> clock source elements, while clock selectors and multipliers can be used
> as terminal clock source.
> 
> The following patch adds a parser for these elements and functions to
> iterate over the tree and find the leaf nodes (clock sources).
> 
> The samplerate set functions were moved to the new clock.c file.
> 
> Signed-off-by: Daniel Mack <daniel at caiaq.de>

Sorry, forgot to squash one hunk into this one.
New version of the patch is below.

Thanks,
Daniel




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