Commit c36b2fc7 authored by Mark Brown's avatar Mark Brown
Browse files

ASoC: Clean up WM8974 PLL configuration 



Don't use a static for WM8974 PLL factors - we don't support more than
one device so it won't happen but no sense in leaving the race condition
hanging around.  Also, pre_div is a single bit and it's a bit simpler if
we move the handling of the factor of 4 in the output into the
coefficient setup.

Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
parent 25cbf465

sound/soc/codecs/wm8974.c

+13 −10
Original line number Diff line number Diff line
@@ -330,36 +330,38 @@ static int wm8974_add_widgets(struct snd_soc_codec *codec) 
}



struct pll_ {

	unsigned int pre_div:4; /* prescale - 1 */

	unsigned int pre_div:1;

	unsigned int n:4;

	unsigned int k;

};



static struct pll_ pll_div;



/* The size in bits of the pll divide multiplied by 10

 * to allow rounding later */

#define FIXED_PLL_SIZE ((1 << 24) * 10)



static void pll_factors(unsigned int target, unsigned int source)

static void pll_factors(struct pll_ *pll_div,

			unsigned int target, unsigned int source)

{

	unsigned long long Kpart;

	unsigned int K, Ndiv, Nmod;



	/* There is a fixed divide by 4 in the output path */

	target *= 4;



	Ndiv = target / source;

	if (Ndiv < 6) {

		source >>= 1;

		pll_div.pre_div = 1;

		source /= 2;

		pll_div->pre_div = 1;

		Ndiv = target / source;

	} else

		pll_div.pre_div = 0;

		pll_div->pre_div = 0;



	if ((Ndiv < 6) || (Ndiv > 12))

		printk(KERN_WARNING

			"WM8974 N value %u outwith recommended range!\n",

			Ndiv);



	pll_div.n = Ndiv;

	pll_div->n = Ndiv;

	Nmod = target % source;

	Kpart = FIXED_PLL_SIZE * (long long)Nmod;
@@ -374,13 +376,14 @@ static void pll_factors(unsigned int target, unsigned int source) 
	/* Move down to proper range now rounding is done */

	K /= 10;



	pll_div.k = K;

	pll_div->k = K;

}



static int wm8974_set_dai_pll(struct snd_soc_dai *codec_dai,

		int pll_id, unsigned int freq_in, unsigned int freq_out)

{

	struct snd_soc_codec *codec = codec_dai->codec;

	struct pll_ pll_div;

	u16 reg;



	if (freq_in == 0 || freq_out == 0) {
@@ -394,7 +397,7 @@ static int wm8974_set_dai_pll(struct snd_soc_dai *codec_dai, 
		return 0;

	}



	pll_factors(freq_out*4, freq_in);

	pll_factors(&pll_div, freq_out, freq_in);



	wm8974_write(codec, WM8974_PLLN, (pll_div.pre_div << 4) | pll_div.n);

	wm8974_write(codec, WM8974_PLLK1, pll_div.k >> 18);

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