[alsa-devel] ASoC, TWL4030 Register defaults

Mark Brown broonie at sirena.org.uk
Thu Nov 20 13:49:12 CET 2008

On Thu, Nov 20, 2008 at 05:21:11PM +0530, naveen krishna ch wrote:
> On Thu, Nov 20, 2008 at 4:53 PM, Mark Brown <broonie at sirena.org.uk> wrote:

> > As I said in reply to your first mail I'd really like to see some sort
> > of explanation as to why you are making these changes - are the defaults
> > in the existing driver wrong?  There seem to be an awful lot of changes
> > here and there's no discussion in the patch as to what they mean.

> The existing driver does the default settings for only one input device
> (Line in) and one output device (Headset out).
> The CODEC supports 5 output devices and 4 input devices.

Thanks for the detail here - this really should go in the changelog for
your patch so people reviewing the history of the driver can see what's

> The default values given by the drivers author are according to his custom
> requirements, expanding them to the CODEC's ability these values can be
> modified.

> What all this patch is doing is setting the default playback and capture
> volumes of various input and output devices to reasonable values.

It is perfectly normal for the default configuration of codecs to not be
suitable for use on a given platform, normally the codec will have the
power on defaults in silicon.  Systems should use something like alsactl
restore to set things up appropriately for their system during startup.

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