diff options
author | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2009-09-30 14:31:38 +0100 |
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committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2009-09-30 15:45:25 +0100 |
commit | c36b2fc73a6c0e7b185b17d594b38398ce1f7fff (patch) | |
tree | 7e547f591106bf5611c0772917fe127f78560a59 /sound | |
parent | 25cbf465207e9616e9b7d362ee166abf296d4c1e (diff) | |
download | blackbird-op-linux-c36b2fc73a6c0e7b185b17d594b38398ce1f7fff.tar.gz blackbird-op-linux-c36b2fc73a6c0e7b185b17d594b38398ce1f7fff.zip |
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>
Diffstat (limited to 'sound')
-rw-r--r-- | sound/soc/codecs/wm8974.c | 23 |
1 files 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); |