[alsa-devel] [PATCH] ASoC: AK4671: add ak4671 codec driver

Joonyoung Shim dofmind at gmail.com
Fri Sep 4 17:37:47 CEST 2009

2009/9/4 Mark Brown <broonie at opensource.wolfsonmicro.com>:
> On Fri, Sep 04, 2009 at 10:30:29AM +0900, Joonyoung Shim wrote:
>> On 9/3/2009 11:02 PM, Mark Brown wrote:
>> >> +  case SND_SOC_BIAS_STANDBY:
>> >> +          if (ak4671->pll_on) {
>> > I suspect this will run into trouble with bypass paths (which do appear
>> > to exist if I read the DAPM routes correctly).  If a bypass path is
>> > active then the CODEC will be brought up to full bias out of sync with
>> > any configuration of pll_on by the DAI format configuration.
>> A bypass path should operate regardless pll_on.
> Yes, I'd expect the bypass path itself to be fine.  What I'm concerned
> about is that because with newer ASoC versions the bypass path will
> cause the CODEC to change bias levels independantly of playback and
> record starting the PLL will be configured when the bypass path is
> enabled rather than when record/playback is started.  This may cause
> things to get out of sync.

Right, so i will use SND_SOC_DAPM_DAC_E and SND_SOC_DAPM_ADC_E.
This event handler desides the setting of PLL, then PLL can be
configured regardless the bypass path.

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