Re: [alsa-devel] [PATCH] ASoC: wm8804: Allow fine-grained control of the PLL generation

[Charles Keepax <ckeepax@opensource.wolfsonmicro.com>]

On Wed, Jan 08, 2014 at 10:36:53PM +0100, Daniel Matuschek wrote:
> Signed-off-by: Daniel Matuschek <daniel@matuschek.net>
>

<snip>

>  			pll_div->freqmode = post_table[i].freqmode;
> -			pll_div->mclkdiv = post_table[i].mclkdiv;
> -			target *= post_table[i].div;
> -			break;
> +			if ((mclk_div == WM8804_MCLKDIV_DONTCARE) ||
> +			    ((post_table[i].mclkdiv == 1) &&
> +				(mclk_div == WM8804_MCLKDIV_1)) ||
> +			    ((post_table[i].mclkdiv == 0) &&
> +				(mclk_div == WM8804_MCLKDIV_0))) {

Would probably be nicer to update the post_table to use the new
defines and directly compare.

> +				pll_div->mclkdiv = post_table[i].mclkdiv;
> +				target *= post_table[i].div;
> +				break;
> +			}
>  		}
>  	}
>
> @@ -388,7 +396,7 @@ static int wm8804_set_pll(struct snd_soc_dai *dai, int pll_id,
>  		int ret;
>  		struct pll_div pll_div;
>
> -		ret = pll_factors(&pll_div, freq_out, freq_in);
> +		ret = pll_factors(&pll_div, freq_out, freq_in, pll_id);

This does feel like a slight abuse of pll_id, it feels to me that
using the set_clkdiv callback would be a little more natural from
a user perspective.

>  		if (ret)
>  			return ret;
>
> diff --git a/sound/soc/codecs/wm8804.h b/sound/soc/codecs/wm8804.h
> index 8ec14f5..0365177 100644
> --- a/sound/soc/codecs/wm8804.h
> +++ b/sound/soc/codecs/wm8804.h
> @@ -58,4 +58,11 @@
>
>  #define WM8804_CLKOUT_DIV			1
>
> +#define WM8804_MCLKDIV_DONTCARE			0
> +#define WM8804_MCLKDIV_0			1
> +#define WM8804_MCLKDIV_1			2
> +#define WM8804_PLL_MCLKDIV_DONTCARE		WM8804_MCLKDIV_DONTCARE
> +#define WM8804_PLL_MCLKDIV_0			WM8804_MCLKDIV_0
> +#define WM8804_PLL_MCLKDIV_1			WM8804_MCLKDIV_1

Do we really need two copies of these?

Thanks,
Charles