Messages in this thread | | | Date | Sat, 24 Sep 2016 19:10:42 +0100 | From | Mark Brown <> | Subject | Re: [PATCH v2] ASoC: rk3399_gru_sound: fix recording pop at first attempt |
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On Fri, Sep 23, 2016 at 04:27:37PM -0500, Rob Herring wrote: > On Thu, Sep 22, 2016 at 09:50:06PM +0800, Xing Zheng wrote: > > From: Wonjoon Lee <woojoo.lee@samsung.com>
> > Pop happens when mclk applied but dmic's own boot-time
> This statement doesn't make sense.
It is very clear if you're familiar with the problem domain - because a DMIC is digital it's got an on/off state which means that when it transitions from off and not outputting anything to outputting something you get a sudden DC transition which manifests as a pop in the audio output.
> > Specify dmic delay times in dt to make sure > > clocks are ready earlier than dmic working
> I don't think this really belongs in DT. Seems like better control of > the init order is needed. Or why not just a fixed delay in the driver?
The changelog says this is due to the DMICs having a startup time of their own so needing a delay after they've started. That's going to be a system dependent thing since it'll depend on the specific component selected and DMICs are easily interchangable. [unhandled content-type:application/pgp-signature] | |