[alsa-devel] [PATCH v2 2/2] ASoC: wm8960: Let wm8960 driver configure its bit clock and frame clock

Zidan Wang b50113 at freescale.com
Thu Jan 15 14:34:40 CET 2015


On Wed, Jan 14, 2015 at 07:27:03PM +0000, Mark Brown wrote:
> On Wed, Jan 07, 2015 at 03:31:45PM +0800, Zidan Wang wrote:
> 
> > +	for (i = 0; i < ARRAY_SIZE(dac_divs); ++i) {
> > +		if (wm8960->sysclk == lrclk * dac_divs[i]) {
> > +			for (j = 0; j < ARRAY_SIZE(bclk_divs); ++j) {
> > +				if (wm8960->sysclk ==  wm8960->bclk *
> > +						bclk_divs[j] / 10) {
> > +					goto config_clock;
> > +				}
> > +			}
> > +		}
> > +	}
> > +
> > +	dev_err(codec->dev, "Unsupported sysclk %d\n", wm8960->sysclk);
> > +	return;
> 
> It's a bit awkward using the goto like this.  A more common way of
> writing this is to change the above block to be
> 
> 	if (i == ARRAY_SIZE(dac_divs))
> 		/* return error */
> 
> rather than skipping over the error.  Otherwise this looks good.

Hi Mark,

I found it can't generate bclk for S20_3LE data format.

For 2 channel S20_3LE data format:

bclk = fs * 20 * 2
Sysclk = BCLKDIV * bclk = BCLKDIV * fs * 40
Sysclk = DACDIV * fs * 256

BCLKDIV/DACDIV = 256/40 = 32/5

But BCLKDIV/DACDIV can't be 32/5. So I want to support tdm slot.

bclk = fs * slot_width * slots * channal.

Do you think it make sense, or any other ideas?

Best Regards,
Zidan


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