Re: [alsa-devel] [PATCH] ASoC: core: Support for limiting the volume

On Fri, 2010-05-07 at 14:05 +0300, Peter Ujfalusi wrote:

Add support for the core to limit the maximum volume on an existing control. The function will modify the soc_mixer_control.max value of the given control. The new value must be lower than the original one (chip maximum)

If there is a need for limiting a gain on a given control, than machine drivers can do the following in their snd_soc_dai_link.init function:

snd_soc_limit_volume(codec, "TPA6140A2 Headphone Playback Volume", 21);

This will modify the original 31 (chip maximum) to 21, so user space will not be able to set the gain higher than this.

Signed-off-by: Peter Ujfalusi peter.ujfalusi@nokia.com

Acked-by: Liam Girdwood lrg@slimlogic.co.uk