ASoC: Automatically calculate clock ratio for WM8580

Implement set_sysclk() and then rather than assuming 256fs use the
supplied value to calculate and configure the clock ratio for the
currently used sample rate. As a side effect we also end up
implementing clock selection for the ADC path.

In order to avoid confusion remove the existing set_clkdiv() based
configuration of the clock source for the DAC and update the SMDK64xx
driver (which is the only in-tree user of the CODEC).

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>

3 files changed, 90 insertions, 34 deletions

diff --git a/sound/soc/codecs/wm8580.c b/sound/soc/codecs/wm8580.c
index 9964f02f84e2..7942f917d31e 100644
--- a/sound/soc/codecs/wm8580.c
+++ b/sound/soc/codecs/wm8580.c
@@ -192,6 +192,7 @@ struct wm8580_priv {
         u16 reg_cache[WM8580_MAX_REGISTER + 1];
         struct pll_state a;
         struct pll_state b;
+        int sysclk[2];
 };
 
 static const DECLARE_TLV_DB_SCALE(dac_tlv, -12750, 50, 1);
@@ -464,6 +465,10 @@ static int wm8580_set_dai_pll(struct snd_soc_dai *codec_dai, int pll_id,
         return 0;
 }
 
+static const int wm8580_sysclk_ratios[] = {
+        128, 192, 256, 384, 512, 768, 1152,
+};
+
 /*
  * Set PCM DAI bit size and sample rate.
  */
@@ -473,7 +478,10 @@ static int wm8580_paif_hw_params(struct snd_pcm_substream *substream,
 {
         struct snd_soc_pcm_runtime *rtd = substream->private_data;
         struct snd_soc_codec *codec = rtd->codec;
+        struct wm8580_priv *wm8580 = snd_soc_codec_get_drvdata(codec);
+        u16 paifa = 0;
         u16 paifb = 0;
+        int i, ratio;
 
         /* bit size */
         switch (params_format(params)) {
@@ -492,6 +500,22 @@ static int wm8580_paif_hw_params(struct snd_pcm_substream *substream,
                 return -EINVAL;
         }
 
+        /* Look up the SYSCLK ratio; accept only exact matches */
+        ratio = wm8580->sysclk[dai->id] / params_rate(params);
+        for (i = 0; i < ARRAY_SIZE(wm8580_sysclk_ratios); i++)
+                if (ratio == wm8580_sysclk_ratios[i])
+                        break;
+        if (i == ARRAY_SIZE(wm8580_sysclk_ratios)) {
+                dev_err(codec->dev, "Invalid clock ratio %d/%d\n",
+                        wm8580->sysclk[dai->id], params_rate(params));
+                return -EINVAL;
+        }
+        paifa |= i;
+        dev_dbg(codec->dev, "Running at %dfs with %dHz clock\n",
+                wm8580_sysclk_ratios[i], wm8580->sysclk[dai->driver->id]);
+
+        snd_soc_update_bits(codec, WM8580_PAIF1 + dai->driver->id,
+                            WM8580_AIF_RATE_MASK, paifa);
         snd_soc_update_bits(codec, WM8580_PAIF3 + dai->driver->id,
                             WM8580_AIF_LENGTH_MASK, paifb);
         return 0;
@@ -501,9 +525,11 @@ static int wm8580_set_paif_dai_fmt(struct snd_soc_dai *codec_dai,
                                       unsigned int fmt)
 {
         struct snd_soc_codec *codec = codec_dai->codec;
+        struct wm8580_priv *wm8580 = snd_soc_codec_get_drvdata(codec);
         unsigned int aifa;
         unsigned int aifb;
         int can_invert_lrclk;
+        int sysclk;
 
         aifa = snd_soc_read(codec, WM8580_PAIF1 + codec_dai->driver->id);
         aifb = snd_soc_read(codec, WM8580_PAIF3 + codec_dai->driver->id);
@@ -572,6 +598,8 @@ static int wm8580_set_paif_dai_fmt(struct snd_soc_dai *codec_dai,
                 return -EINVAL;
         }
 
+        sysclk = wm8580->sysclk[codec_dai->driver->id];
+
         snd_soc_write(codec, WM8580_PAIF1 + codec_dai->driver->id, aifa);
         snd_soc_write(codec, WM8580_PAIF3 + codec_dai->driver->id, aifb);
 
@@ -611,28 +639,6 @@ static int wm8580_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
                 snd_soc_write(codec, WM8580_PLLB4, reg);
                 break;
 
-        case WM8580_DAC_CLKSEL:
-                reg = snd_soc_read(codec, WM8580_CLKSEL);
-                reg &= ~WM8580_CLKSEL_DAC_CLKSEL_MASK;
-
-                switch (div) {
-                case WM8580_CLKSRC_MCLK:
-                        break;
-
-                case WM8580_CLKSRC_PLLA:
-                        reg |= WM8580_CLKSEL_DAC_CLKSEL_PLLA;
-                        break;
-
-                case WM8580_CLKSRC_PLLB:
-                        reg |= WM8580_CLKSEL_DAC_CLKSEL_PLLB;
-                        break;
-
-                default:
-                        return -EINVAL;
-                }
-                snd_soc_write(codec, WM8580_CLKSEL, reg);
-                break;
-
         case WM8580_CLKOUTSRC:
                 reg = snd_soc_read(codec, WM8580_PLLB4);
                 reg &= ~WM8580_PLLB4_CLKOUTSRC_MASK;
@@ -666,6 +672,55 @@ static int wm8580_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
         return 0;
 }
 
+static int wm8580_set_sysclk(struct snd_soc_dai *dai, int clk_id,
+                             unsigned int freq, int dir)
+{
+        struct snd_soc_codec *codec = dai->codec;
+        struct wm8580_priv *wm8580 = snd_soc_codec_get_drvdata(codec);
+        int sel, sel_mask, sel_shift;
+
+        switch (dai->driver->id) {
+        case WM8580_DAI_PAIFTX:
+                sel_mask = 0x3;
+                sel_shift = 0;
+                break;
+
+        case WM8580_DAI_PAIFRX:
+                sel_mask = 0xc;
+                sel_shift = 2;
+                break;
+
+        default:
+                BUG_ON("Unknown DAI driver ID\n");
+                return -EINVAL;
+        }
+
+        switch (clk_id) {
+        case WM8580_CLKSRC_ADCMCLK:
+                if (dai->id != WM8580_DAI_PAIFTX)
+                        return -EINVAL;
+                sel = 0 << sel_shift;
+                break;
+        case WM8580_CLKSRC_PLLA:
+                sel = 1 << sel_shift;
+                break;
+        case WM8580_CLKSRC_PLLB:
+                sel = 2 << sel_shift;
+                break;
+        case WM8580_CLKSRC_MCLK:
+                sel = 3 << sel_shift;
+                break;
+        default:
+                dev_err(codec->dev, "Unknown clock %d\n", clk_id);
+                return -EINVAL;
+        }
+
+        /* We really should validate PLL settings but not yet */
+        wm8580->sysclk[dai->id] = freq;
+
+        return snd_soc_update_bits(codec, WM8580_CLKSEL, sel, sel_mask);
+}
+
 static int wm8580_digital_mute(struct snd_soc_dai *codec_dai, int mute)
 {
         struct snd_soc_codec *codec = codec_dai->codec;
@@ -719,6 +774,7 @@ static int wm8580_set_bias_level(struct snd_soc_codec *codec,
                         SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
 
 static struct snd_soc_dai_ops wm8580_dai_ops_playback = {
+        .set_sysclk     = wm8580_set_sysclk,
         .hw_params      = wm8580_paif_hw_params,
         .set_fmt        = wm8580_set_paif_dai_fmt,
         .set_clkdiv     = wm8580_set_dai_clkdiv,
@@ -727,6 +783,7 @@ static struct snd_soc_dai_ops wm8580_dai_ops_playback = {
 };
 
 static struct snd_soc_dai_ops wm8580_dai_ops_capture = {
+        .set_sysclk     = wm8580_set_sysclk,
         .hw_params      = wm8580_paif_hw_params,
         .set_fmt        = wm8580_set_paif_dai_fmt,
         .set_clkdiv     = wm8580_set_dai_clkdiv,
diff --git a/sound/soc/codecs/wm8580.h b/sound/soc/codecs/wm8580.h
index 8328ef667593..1d34656d0dcb 100644
--- a/sound/soc/codecs/wm8580.h
+++ b/sound/soc/codecs/wm8580.h
@@ -19,14 +19,14 @@
 #define WM8580_PLLB  2
 
 #define WM8580_MCLK       1
-#define WM8580_DAC_CLKSEL 2
-#define WM8580_CLKOUTSRC  3
+#define WM8580_CLKOUTSRC  2
 
-#define WM8580_CLKSRC_MCLK 1
-#define WM8580_CLKSRC_PLLA 2
-#define WM8580_CLKSRC_PLLB 3
-#define WM8580_CLKSRC_OSC  4
-#define WM8580_CLKSRC_NONE 5
+#define WM8580_CLKSRC_MCLK    1
+#define WM8580_CLKSRC_PLLA    2
+#define WM8580_CLKSRC_PLLB    3
+#define WM8580_CLKSRC_OSC     4
+#define WM8580_CLKSRC_NONE    5
+#define WM8580_CLKSRC_ADCMCLK 6
 
 #define WM8580_DAI_PAIFRX 0
 #define WM8580_DAI_PAIFTX 1
diff --git a/sound/soc/s3c24xx/smdk64xx_wm8580.c b/sound/soc/s3c24xx/smdk64xx_wm8580.c
index 5c21e26da075..91367f7bfec3 100644
--- a/sound/soc/s3c24xx/smdk64xx_wm8580.c
+++ b/sound/soc/s3c24xx/smdk64xx_wm8580.c
@@ -113,14 +113,13 @@ static int smdk64xx_hw_params(struct snd_pcm_substream *substream,
         if (ret < 0)
                 return ret;
 
-        /* Explicitly set WM8580-DAC to source from MCLK */
-        ret = snd_soc_dai_set_clkdiv(codec_dai, WM8580_DAC_CLKSEL,
-                                        WM8580_CLKSRC_MCLK);
+        ret = snd_soc_dai_set_pll(codec_dai, WM8580_PLLA, 0,
+                                        SMDK64XX_WM8580_FREQ, pll_out);
         if (ret < 0)
                 return ret;
 
-        ret = snd_soc_dai_set_pll(codec_dai, WM8580_PLLA, 0,
-                                        SMDK64XX_WM8580_FREQ, pll_out);
+        ret = snd_soc_dai_set_sysclk(codec_dai, WM8580_CLKSRC_PLLA,
+                                     pll_out, SND_SOC_CLOCK_IN);
         if (ret < 0)
                 return ret;