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ASoC: codec: wm9860: Refactor PLL out freq search

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Add a separate function for deriving (sysclk, lrclk, bclk)
when the clock is auto or pll.

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Daniel Baluta 2017-04-04 19:45:13 +03:00 committed by Mark Brown
parent 3c01b9ee2a
commit 84fdc00d51
1 changed files with 64 additions and 29 deletions
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93
sound/soc/codecs/wm8960.c
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@ -672,10 +672,70 @@ int wm8960_configure_sysclk(struct wm8960_priv *wm8960, int mclk,
return *bclk_idx;
}
/**
* wm8960_configure_pll - checks if there is a PLL out frequency available
* The PLL out frequency must be chosen such that:
* - sysclk = lrclk * dac_divs
* - freq_out = sysclk * sysclk_divs
* - 10 * sysclk = bclk * bclk_divs
*
* @codec: codec structure
* @freq_in: input frequency used to derive freq out via PLL
* @sysclk_idx: sysclk_divs index for found sysclk
* @dac_idx: dac_divs index for found lrclk
* @bclk_idx: bclk_divs index for found bclk
*
* Returns:
* -1, in case no PLL frequency out available was found
* >=0, in case we could derive bclk, lrclk, sysclk from PLL out using
* (@sysclk_idx, @dac_idx, @bclk_idx) dividers
*/
static
int wm8960_configure_pll(struct snd_soc_codec *codec, int freq_in,
int *sysclk_idx, int *dac_idx, int *bclk_idx)
{
struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
int sysclk, bclk, lrclk, freq_out;
int diff, best_freq_out;
int i, j, k;
bclk = wm8960->bclk;
lrclk = wm8960->lrclk;
*bclk_idx = -1;
for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) {
if (sysclk_divs[i] == -1)
continue;
for (j = 0; j < ARRAY_SIZE(dac_divs); ++j) {
sysclk = lrclk * dac_divs[j];
freq_out = sysclk * sysclk_divs[i];
for (k = 0; k < ARRAY_SIZE(bclk_divs); ++k) {
if (!is_pll_freq_available(freq_in, freq_out))
continue;
diff = sysclk - bclk * bclk_divs[k] / 10;
if (diff == 0) {
*sysclk_idx = i;
*dac_idx = j;
*bclk_idx = k;
best_freq_out = freq_out;
break;
}
}
}
}
if (*bclk_idx != -1)
wm8960_set_pll(codec, freq_in, best_freq_out);
return *bclk_idx;
}
static int wm8960_configure_clocking(struct snd_soc_codec *codec)
{
struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
int sysclk, bclk, lrclk, freq_out, freq_in;
int freq_out, freq_in;
u16 iface1 = snd_soc_read(codec, WM8960_IFACE1);
int i, j, k;
int ret;
@ -692,8 +752,6 @@ static int wm8960_configure_clocking(struct snd_soc_codec *codec)
}
freq_in = wm8960->freq_in;
bclk = wm8960->bclk;
lrclk = wm8960->lrclk;
/*
* If it's sysclk auto mode, check if the MCLK can provide sysclk or
* not. If MCLK can provide sysclk, using MCLK to provide sysclk
@ -720,33 +778,10 @@ static int wm8960_configure_clocking(struct snd_soc_codec *codec)
return -EINVAL;
}
}
/* get a available pll out frequency and set pll */
for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) {
if (sysclk_divs[i] == -1)
continue;
for (j = 0; j < ARRAY_SIZE(dac_divs); ++j) {
sysclk = lrclk * dac_divs[j];
freq_out = sysclk * sysclk_divs[i];
for (k = 0; k < ARRAY_SIZE(bclk_divs); ++k) {
if (sysclk == bclk * bclk_divs[k] / 10 &&
is_pll_freq_available(freq_in, freq_out)) {
wm8960_set_pll(codec,
freq_in, freq_out);
break;
} else {
continue;
}
}
if (k != ARRAY_SIZE(bclk_divs))
break;
}
if (j != ARRAY_SIZE(dac_divs))
break;
}
if (i == ARRAY_SIZE(sysclk_divs)) {
dev_err(codec->dev, "failed to configure clock\n");
ret = wm8960_configure_pll(codec, freq_in, &i, &j, &k);
if (ret < 0) {
dev_err(codec->dev, "failed to configure clock via PLL\n");
return -EINVAL;
}