Commit c36b2fc7 authored by Mark Brown's avatar Mark Brown

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
...@@ -330,36 +330,38 @@ static int wm8974_add_widgets(struct snd_soc_codec *codec) ...@@ -330,36 +330,38 @@ static int wm8974_add_widgets(struct snd_soc_codec *codec)
} }
struct pll_ { struct pll_ {
unsigned int pre_div:4; /* prescale - 1 */ unsigned int pre_div:1;
unsigned int n:4; unsigned int n:4;
unsigned int k; unsigned int k;
}; };
static struct pll_ pll_div;
/* The size in bits of the pll divide multiplied by 10 /* The size in bits of the pll divide multiplied by 10
* to allow rounding later */ * to allow rounding later */
#define FIXED_PLL_SIZE ((1 << 24) * 10) #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 long long Kpart;
unsigned int K, Ndiv, Nmod; unsigned int K, Ndiv, Nmod;
/* There is a fixed divide by 4 in the output path */
target *= 4;
Ndiv = target / source; Ndiv = target / source;
if (Ndiv < 6) { if (Ndiv < 6) {
source >>= 1; source /= 2;
pll_div.pre_div = 1; pll_div->pre_div = 1;
Ndiv = target / source; Ndiv = target / source;
} else } else
pll_div.pre_div = 0; pll_div->pre_div = 0;
if ((Ndiv < 6) || (Ndiv > 12)) if ((Ndiv < 6) || (Ndiv > 12))
printk(KERN_WARNING printk(KERN_WARNING
"WM8974 N value %u outwith recommended range!\n", "WM8974 N value %u outwith recommended range!\n",
Ndiv); Ndiv);
pll_div.n = Ndiv; pll_div->n = Ndiv;
Nmod = target % source; Nmod = target % source;
Kpart = FIXED_PLL_SIZE * (long long)Nmod; Kpart = FIXED_PLL_SIZE * (long long)Nmod;
...@@ -374,13 +376,14 @@ static void pll_factors(unsigned int target, unsigned int source) ...@@ -374,13 +376,14 @@ static void pll_factors(unsigned int target, unsigned int source)
/* Move down to proper range now rounding is done */ /* Move down to proper range now rounding is done */
K /= 10; K /= 10;
pll_div.k = K; pll_div->k = K;
} }
static int wm8974_set_dai_pll(struct snd_soc_dai *codec_dai, static int wm8974_set_dai_pll(struct snd_soc_dai *codec_dai,
int pll_id, unsigned int freq_in, unsigned int freq_out) int pll_id, unsigned int freq_in, unsigned int freq_out)
{ {
struct snd_soc_codec *codec = codec_dai->codec; struct snd_soc_codec *codec = codec_dai->codec;
struct pll_ pll_div;
u16 reg; u16 reg;
if (freq_in == 0 || freq_out == 0) { if (freq_in == 0 || freq_out == 0) {
...@@ -394,7 +397,7 @@ static int wm8974_set_dai_pll(struct snd_soc_dai *codec_dai, ...@@ -394,7 +397,7 @@ static int wm8974_set_dai_pll(struct snd_soc_dai *codec_dai,
return 0; 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_PLLN, (pll_div.pre_div << 4) | pll_div.n);
wm8974_write(codec, WM8974_PLLK1, pll_div.k >> 18); wm8974_write(codec, WM8974_PLLK1, pll_div.k >> 18);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment