[alsa-devel] [PATCH 0/8] ASoC: TWL4030: DAPM implementation for outputs (playback)

Peter Ujfalusi peter.ujfalusi at nokia.com
Tue Dec 9 07:51:58 CET 2008

On Monday 08 December 2008 15:20:41 ext Mark Brown wrote:
> On Mon, Dec 08, 2008 at 10:09:00AM +0200, Peter Ujfalusi wrote:
> > Based on the output routing selections all the corresponding DAC and
> > analog PGA on the chain will be powered on.
> One other question: how does this all interact with the existing power
> control in set_bias_level()?

This is a good question.
As I see: when the twl4030_power_down is called from the 
twl4030_set_bias_level (SND_SOC_BIAS_STANDBY, SND_SOC_BIAS_OFF) it sets the 
codec to power-off state (CODEC_MODE:CODECPDZ = 0), which effectively turns 
off the digital filter, analog section, so basically everything.
When the CODECPDZ is 0, APGA, DAC, analog output settings have no effect (they 
are powered off)


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