[PATCH 1/4] ASoC: sgtl5000: give it a ramping time before writting

Shawn Guo shawn.guo at linaro.org
Mon Jul 1 10:04:55 EDT 2013


On Mon, Jul 01, 2013 at 11:07:10AM +0100, Mark Brown wrote:
> On Mon, Jul 01, 2013 at 04:16:08PM +0800, Shawn Guo wrote:
> 
> > +	/*
> > +	 * It seems that sgtl5000 takes a longer time to get the registers
> > +	 * ready for write than bread.  Let's give it a ramping time before
> > +	 * the first write goes.
> > +	 */
> > +	msleep(50);
> > +
> >  	/* Ensure sgtl5000 will start with sane register values */
> >  	ret = sgtl5000_fill_defaults(sgtl5000);
> >  	if (ret)
> 
> This seems like a really odd place to add the sleep - I'd have expected
> this to be a part of or just after the reset operation.

Since I do not see any reset operation between clk_prepare_enable()
and sgtl5000_fill_defaults(), so I will move the sleep into
sgtl5000_fill_defaults() call.

> It's a *really*
> long sleep too, though if that's what you need that's what you need.
> 
Yeah, from my testing it's what we need.


> Also "bread" :)

Yeah, I was really hungry when writing the comment.

Shawn




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