[alsa-devel] [PATCH] New ASoC Drivers for ADI AD1938 codec

Mark Brown broonie at opensource.wolfsonmicro.com
Mon Jul 13 11:15:38 CEST 2009

On Mon, Jul 13, 2009 at 04:12:14PM +0800, 宋宝华 wrote:

> I want to use ADC/DAC widgets.
> static const struct snd_soc_dapm_widget ad1938_dapm_widgets[] = {
>         SND_SOC_DAPM_DAC("DAC", "HiFi Playback", AD1938_DAC_CTRL0, 0, 1),
>         SND_SOC_DAPM_ADC("ADC", "HiFi Capture", AD1938_ADC_CTRL0, 0, 1),
> };
> But for this AD1938 codec, DAC's work depends on ADC is powered on in
> hardware.  I think there is no any mechanism to handle this kind of
> strange depending now.  So is there a generic way to handle this?

Make the ADC power a SND_SOC_DAPM_SUPPLY() supplying both the DAC and
the ADC, with the ADC widget marged as having no power management.

More information about the Alsa-devel mailing list