Re: [PATCH v4 1/2] Partially revert ASoC: qcom: Fix enabling BCLK and LRCLK in LPAIF invalid state

[Srinivasa Rao Mandadapu]

Thanks Mark for Your time!!!

On 12/1/2020 11:21 PM, Mark Brown wrote:
> On Tue, Dec 01, 2020 at 11:01:21PM +0530, Srinivasa Rao Mandadapu wrote:
> > On 11/30/2020 6:16 PM, Mark Brown wrote:
> > > Part of this commit message says that the problem was making the registers
> > > non-volatile but both the change and the rest of the commit message say
> > > that the issue was that the registers were made volatile.  I'm also
> > > still unclear as to what the issue is either way - how does reading the
> > > state of the registers from the hardware instead of the cache affect
> > > things?
> > Initial problem was, during playback if device suspended, I2S and DMA
> > control registers
> > are getting reset and unable to recover playback after resume.
> > As these registers were non volatile registers, driver is not getting actual
> > register value
> > and unable to report error state to application. Due to this application
> > keeps on polling for HW current pointer state and not exited from PCM
> > running state.
> > Later from review comments by Srinivas kandagatla, I got to know
> >
> > about regcache sync APIs, which can be used  to sync cache after resume and
> >
> > HW registers can be updated with  original values. With that playback can be
> > continued.
> >
> > So is the reason, I am reverting partial changes in the commit b1824968221c.
> I don't understand why a fix for the register cache not being in sync
> with the hardware doesn't involve syncing the register cache with the
> hardware.

I am sorry I couldn't understand your point. Could you please elaborate 
your query?

Actually I posted V5 version based on review comments.

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