[alsa-devel][PATCH 2/4] ASoC: wm8960: Let wm8960 driver configure its bit clock and frame clock

From: Zidan Wang
Date: Tue Dec 30 2014 - 22:38:39 EST


wm8960 codec driver missing configure its bit clock and frame clock, so add
support for it. It will calculate a appropriate frequency dividing ratio
according to the system clock, bit clock and frame clock, then set the
corresponding registers.

Signed-off-by: Zidan Wang <b50113@xxxxxxxxxxxxx>
---
sound/soc/codecs/wm8960.c | 108 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 108 insertions(+)

diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c
index 1a5f47b..86a5489 100644
--- a/sound/soc/codecs/wm8960.c
+++ b/sound/soc/codecs/wm8960.c
@@ -127,6 +127,8 @@ struct wm8960_priv {
struct snd_soc_dapm_widget *out3;
bool deemph;
int playback_fs;
+ int bclk;
+ int sysclk;
struct wm8960_data pdata;
};

@@ -563,6 +565,79 @@ static struct {
{ 8000, 5 },
};

+/* Multiply 256 for internal 256 div */
+static const int dac_divs[] = { 256, 384, 512, 768, 1024, 1408, 1536 };
+
+/* Multiply 10 to eliminate decimials */
+static const int bclk_divs[] = {
+ 10, 15, 20, 30, 40, 55, 60, 80, 110,
+ 120, 160, 220, 240, 320, 320, 320
+};
+
+static void wm8960_configure_clocking(struct snd_soc_codec *codec,
+ int stream, int lrclk)
+{
+ struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
+ u16 iface1 = snd_soc_read(codec, WM8960_IFACE1);
+ u16 iface2 = snd_soc_read(codec, WM8960_IFACE2);
+ int i, j;
+
+ if (!(iface1 & (1<<6))) {
+ dev_dbg(codec->dev,
+ "Codec is slave mode, no need to configure clock\n");
+ return;
+ }
+
+ if (!wm8960->sysclk) {
+ dev_dbg(codec->dev, "No SYSCLK configured\n");
+ return;
+ }
+
+ if (!wm8960->bclk || !lrclk) {
+ dev_dbg(codec->dev, "No audio clocks configured\n");
+ return;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(dac_divs); ++i) {
+ if (wm8960->sysclk == lrclk * dac_divs[i]) {
+ for (j = 0; j < ARRAY_SIZE(bclk_divs); ++j) {
+ if (wm8960->sysclk == wm8960->bclk *
+ bclk_divs[j] / 10) {
+ /* configure frame clock */
+ if (iface2 & (1<<6))
+ /* If ADCLRC configure as GPIO
+ * pin, DACLRC pin is used as
+ * a frame clock for ADCs and
+ * DACs */
+ snd_soc_update_bits(codec,
+ WM8960_CLOCK1,
+ 0x7 << 3,
+ i << 3);
+ else if (SNDRV_PCM_STREAM_PLAYBACK
+ == stream)
+ snd_soc_update_bits(codec,
+ WM8960_CLOCK1,
+ 0x7 << 3,
+ i << 3);
+ else if (SNDRV_PCM_STREAM_CAPTURE
+ == stream)
+ snd_soc_update_bits(codec,
+ WM8960_CLOCK1,
+ 0x7 << 6,
+ i << 6);
+
+ /* configure bit clock */
+ snd_soc_update_bits(codec,
+ WM8960_CLOCK2, 0xf, j);
+ return;
+ }
+ }
+ }
+ }
+
+ dev_err(codec->dev, "Unsupported sysclk %d\n", wm8960->sysclk);
+}
+
static int wm8960_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai)
@@ -572,6 +647,10 @@ static int wm8960_hw_params(struct snd_pcm_substream *substream,
u16 iface = snd_soc_read(codec, WM8960_IFACE1) & 0xfff3;
int i;

+ wm8960->bclk = snd_soc_params_to_bclk(params);
+ if (params_channels(params) == 1)
+ wm8960->bclk *= 2;
+
/* bit size */
switch (params_width(params)) {
case 16:
@@ -602,6 +681,10 @@ static int wm8960_hw_params(struct snd_pcm_substream *substream,

/* set iface */
snd_soc_write(codec, WM8960_IFACE1, iface);
+
+ wm8960_configure_clocking(codec, substream->stream,
+ params_rate(params));
+
return 0;
}

@@ -943,6 +1026,30 @@ static int wm8960_set_bias_level(struct snd_soc_codec *codec,
return wm8960->set_bias_level(codec, level);
}

+static int wm8960_set_dai_sysclk(struct snd_soc_dai *dai, int clk_id,
+ unsigned int freq, int dir)
+{
+ struct snd_soc_codec *codec = dai->codec;
+ struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
+
+ switch (clk_id) {
+ case WM8960_SYSCLK_MCLK:
+ snd_soc_update_bits(codec, WM8960_CLOCK1,
+ 0x1, WM8960_SYSCLK_MCLK);
+ break;
+ case WM8960_SYSCLK_PLL:
+ snd_soc_update_bits(codec, WM8960_CLOCK1,
+ 0x1, WM8960_SYSCLK_PLL);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ wm8960->sysclk = freq;
+
+ return 0;
+}
+
#define WM8960_RATES SNDRV_PCM_RATE_8000_48000

#define WM8960_FORMATS \
@@ -955,6 +1062,7 @@ static const struct snd_soc_dai_ops wm8960_dai_ops = {
.set_fmt = wm8960_set_dai_fmt,
.set_clkdiv = wm8960_set_dai_clkdiv,
.set_pll = wm8960_set_dai_pll,
+ .set_sysclk = wm8960_set_dai_sysclk,
};

static struct snd_soc_dai_driver wm8960_dai = {
--
1.9.1

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