From c36b2fc73a6c0e7b185b17d594b38398ce1f7fff Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Wed, 30 Sep 2009 14:31:38 +0100 Subject: [PATCH] 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 --- sound/soc/codecs/wm8974.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) 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); -- 2.20.1