From: Mark Brown <broonie@opensource.wolfsonmicro.com>
Date: Wed, 30 Sep 2009 13:31:38 +0000 (+0100)
Subject: ASoC: Clean up WM8974 PLL configuration
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=c36b2fc73a6c0e7b185b17d594b38398ce1f7fff;p=openwrt%2Fstaging%2Fblogic.git

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: Mark Brown <broonie@opensource.wolfsonmicro.com>
---

diff --git a/sound/soc/codecs/wm8974.c b/sound/soc/codecs/wm8974.c
index 5104c8aa34f6..f30f86b3bda0 100644
--- a/sound/soc/codecs/wm8974.c
+++ b/sound/soc/codecs/wm8974.c
@@ -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);