[alsa-devel] [PATCH 07/11] ASoC: tegra: Add tegra-das driver

Stephen Warren swarren at nvidia.com
Thu Jan 6 22:58:22 CET 2011

Mark Brown wrote:
> On Thu, Jan 06, 2011 at 09:46:10AM -0800, Stephen Warren wrote:
> > Finally, all the above is really talking about what a machine driver
> > "allows". It'd still be nice if the default (in the absence of any
> > alsamixer or UCM setup) was that opening e.g. hw:0,0 would allow some
> > simple use of the audio, e.g. playback to primary output, capture from
> > primary input, so that simple testing could be performed without having
> Define "primary output" and "primary input" and what a sensible setup
> for them is; it's not terribly clear what they are always.  Besides,
> it's not like ALSA supports *any* use without alsa-lib or equivalent and
> if you've got that far you've already got the infrastructure you need to
> do configuration anyway more or less.  You'd need to do that to develop
> the default settings anyway, and once you've done that you've then got
> to translate them back into kernel space.
> Probably the only people who'd get much from this are people who are
> using a reference system with no userspace provided, which is fairly
> unusual.  If a userspace is being shipped then including config there
> generally isn't much of an issue, and if you're bringing up a board then
> you're in the situation where you need to work out what the setup that's
> needed is.

People who're bringup up a board without expecting they need to know
anything about alsa-lib would get a bit out of this:-) :-)

So I guess what'd help me through this the most is knowing exactly how
the user-space is configured; is this all stuff in /etc/asound.conf or
some other config file? When you were talking about user-space earlier,
I was thinking of writing a custom application per board/machine to
configure the system at e.g. boot time (or libraries that apps would use),
which didn't sound appealing; maybe that's part of my misunderstanding.

Are there any public examples for ASoC in particular that I can read in
concert with the driver source to get the idea? I did find
alsa-lib.git/src/conf but that seems to only cover desktop PCs, not
ASoC drivers.



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