ASoC: wm8960: update pll and clock setting function

Add sysclk auto mode. When it's sysclk auto mode, if the MCLK is
available for clock configure, using MCLK to provide sysclk directly,
otherwise, search a available pll out frequcncy and set pll.

Configure clock in hw_params may cause problems when using bypass style
paths without hw_params in machine driver getting called. So add configure
clock to set_bias_level.

Signed-off-by: Zidan Wang <[e-mail]>
Acked-by: Charles Keepax <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/codecs/wm8960.c

···
 #define WM8960_DISOP     0x40
 #define WM8960_DRES_MASK 0x30
 
+static bool is_pll_freq_available(unsigned int source, unsigned int target);
+static int wm8960_set_pll(struct snd_soc_codec *codec,
+		unsigned int freq_in, unsigned int freq_out);
 /*
  * wm8960 register cache
  * We can't read the WM8960 register space when we are
···
 	struct snd_soc_dapm_widget *rout1;
 	struct snd_soc_dapm_widget *out3;
 	bool deemph;
-	int playback_fs;
+	int lrclk;
 	int bclk;
 	int sysclk;
+	int clk_id;
+	int freq_in;
+	bool is_stream_in_use[2];
 	struct wm8960_data pdata;
 };
 
···
 	if (wm8960->deemph) {
 		best = 1;
 		for (i = 2; i < ARRAY_SIZE(deemph_settings); i++) {
-			if (abs(deemph_settings[i] - wm8960->playback_fs) <
-			    abs(deemph_settings[best] - wm8960->playback_fs))
+			if (abs(deemph_settings[i] - wm8960->lrclk) <
+			    abs(deemph_settings[best] - wm8960->lrclk))
 				best = i;
 		}
 
···
 	{  8000, 5 },
 };
 
+/* -1 for reserved value */
+static const int sysclk_divs[] = { 1, -1, 2, -1 };
+
 /* Multiply 256 for internal 256 div */
 static const int dac_divs[] = { 256, 384, 512, 768, 1024, 1408, 1536 };
 
···
 	120, 160, 220, 240, 320, 320, 320
 };
 
-static void wm8960_configure_clocking(struct snd_soc_codec *codec,
-		bool tx, int lrclk)
+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;
 	u16 iface1 = snd_soc_read(codec, WM8960_IFACE1);
-	u16 iface2 = snd_soc_read(codec, WM8960_IFACE2);
-	u32 sysclk;
-	int i, j;
+	int i, j, k;
 
 	if (!(iface1 & (1<<6))) {
 		dev_dbg(codec->dev,
 			"Codec is slave mode, no need to configure clock\n");
-		return;
+		return 0;
 	}
 
-	if (!wm8960->sysclk) {
-		dev_dbg(codec->dev, "No SYSCLK configured\n");
-		return;
+	if (wm8960->clk_id != WM8960_SYSCLK_MCLK && !wm8960->freq_in) {
+		dev_err(codec->dev, "No MCLK configured\n");
+		return -EINVAL;
 	}
 
-	if (!wm8960->bclk || !lrclk) {
-		dev_dbg(codec->dev, "No audio clocks configured\n");
-		return;
+	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
+	 * directly. Otherwise, auto select a available pll out frequency
+	 * and set PLL.
+	 */
+	if (wm8960->clk_id == WM8960_SYSCLK_AUTO) {
+		/* disable the PLL and using MCLK to provide sysclk */
+		wm8960_set_pll(codec, 0, 0);
+		freq_out = freq_in;
+	} else if (wm8960->sysclk) {
+		freq_out = wm8960->sysclk;
+	} else {
+		dev_err(codec->dev, "No SYSCLK configured\n");
+		return -EINVAL;
 	}
 
-	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) {
-				sysclk = wm8960->bclk * bclk_divs[j] / 10;
-				if (wm8960->sysclk == sysclk)
+	/* check if the sysclk frequency is available. */
+	for (i = 0; i < ARRAY_SIZE(sysclk_divs); ++i) {
+		if (sysclk_divs[i] == -1)
+			continue;
+		sysclk = freq_out / sysclk_divs[i];
+		for (j = 0; j < ARRAY_SIZE(dac_divs); ++j) {
+			if (sysclk == dac_divs[j] * lrclk) {
+				for (k = 0; k < ARRAY_SIZE(bclk_divs); ++k)
+					if (sysclk == bclk * bclk_divs[k] / 10)
+						break;
+				if (k != ARRAY_SIZE(bclk_divs))
 					break;
 			}
-			if(j != ARRAY_SIZE(bclk_divs))
+		}
+		if (j != ARRAY_SIZE(dac_divs))
+			break;
+	}
+
+	if (i != ARRAY_SIZE(sysclk_divs)) {
+		goto configure_clock;
+	} else if (wm8960->clk_id != WM8960_SYSCLK_AUTO) {
+		dev_err(codec->dev, "failed to configure clock\n");
+		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(dac_divs)) {
-		dev_err(codec->dev, "Unsupported sysclk %d\n", wm8960->sysclk);
-		return;
+	if (i == ARRAY_SIZE(sysclk_divs)) {
+		dev_err(codec->dev, "failed to configure clock\n");
+		return -EINVAL;
 	}
 
-	/*
-	 * configure frame clock. If ADCLRC configure as GPIO pin, DACLRC
-	 * pin is used as a frame clock for ADCs and DACs.
-	 */
-	if (iface2 & (1<<6))
-		snd_soc_update_bits(codec, WM8960_CLOCK1, 0x7 << 3, i << 3);
-	else if (tx)
-		snd_soc_update_bits(codec, WM8960_CLOCK1, 0x7 << 3, i << 3);
-	else if (!tx)
-		snd_soc_update_bits(codec, WM8960_CLOCK1, 0x7 << 6, i << 6);
+configure_clock:
+	/* configure sysclk clock */
+	snd_soc_update_bits(codec, WM8960_CLOCK1, 3 << 1, i << 1);
+
+	/* configure frame clock */
+	snd_soc_update_bits(codec, WM8960_CLOCK1, 0x7 << 3, j << 3);
+	snd_soc_update_bits(codec, WM8960_CLOCK1, 0x7 << 6, j << 6);
 
 	/* configure bit clock */
-	snd_soc_update_bits(codec, WM8960_CLOCK2, 0xf, j);
+	snd_soc_update_bits(codec, WM8960_CLOCK2, 0xf, k);
+
+	return 0;
 }
 
 static int wm8960_hw_params(struct snd_pcm_substream *substream,
···
 		return -EINVAL;
 	}
 
+	wm8960->lrclk = params_rate(params);
 	/* Update filters for the new rate */
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		wm8960->playback_fs = params_rate(params);
+	if (tx) {
 		wm8960_set_deemph(codec);
 	} else {
 		for (i = 0; i < ARRAY_SIZE(alc_rates); i++)
···
 	/* set iface */
 	snd_soc_write(codec, WM8960_IFACE1, iface);
 
-	wm8960_configure_clocking(codec, tx, params_rate(params));
+	wm8960->is_stream_in_use[tx] = true;
+
+	if (snd_soc_codec_get_bias_level(codec) == SND_SOC_BIAS_ON &&
+	    !wm8960->is_stream_in_use[!tx])
+		return wm8960_configure_clocking(codec);
+
+	return 0;
+}
+
+static int wm8960_hw_free(struct snd_pcm_substream *substream,
+		struct snd_soc_dai *dai)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
+	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
+
+	wm8960->is_stream_in_use[tx] = false;
 
 	return 0;
 }
···
 				      enum snd_soc_bias_level level)
 {
 	struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
+	u16 pm2 = snd_soc_read(codec, WM8960_POWER2);
 	int ret;
 
 	switch (level) {
···
 				}
 			}
 
+			ret = wm8960_configure_clocking(codec);
+			if (ret)
+				return ret;
+
 			/* Set VMID to 2x50k */
 			snd_soc_update_bits(codec, WM8960_POWER1, 0x180, 0x80);
 			break;
 
 		case SND_SOC_BIAS_ON:
+			/*
+			 * If it's sysclk auto mode, and the pll is enabled,
+			 * disable the pll
+			 */
+			if (wm8960->clk_id == WM8960_SYSCLK_AUTO && (pm2 & 0x1))
+				wm8960_set_pll(codec, 0, 0);
+
 			if (!IS_ERR(wm8960->mclk))
 				clk_disable_unprepare(wm8960->mclk);
 			break;
···
 					 enum snd_soc_bias_level level)
 {
 	struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
+	u16 pm2 = snd_soc_read(codec, WM8960_POWER2);
 	int reg, ret;
 
 	switch (level) {
···
 					return ret;
 				}
 			}
+
+			ret = wm8960_configure_clocking(codec);
+			if (ret)
+				return ret;
+
 			break;
 
 		case SND_SOC_BIAS_ON:
+			/*
+			 * If it's sysclk auto mode, and the pll is enabled,
+			 * disable the pll
+			 */
+			if (wm8960->clk_id == WM8960_SYSCLK_AUTO && (pm2 & 0x1))
+				wm8960_set_pll(codec, 0, 0);
+
 			if (!IS_ERR(wm8960->mclk))
 				clk_disable_unprepare(wm8960->mclk);
 
···
 	u32 k:24;
 };
 
+static bool is_pll_freq_available(unsigned int source, unsigned int target)
+{
+	unsigned int Ndiv;
+
+	if (source == 0 || target == 0)
+		return false;
+
+	/* Scale up target to PLL operating frequency */
+	target *= 4;
+	Ndiv = target / source;
+
+	if (Ndiv < 6) {
+		source >>= 1;
+		Ndiv = target / source;
+	}
+
+	if ((Ndiv < 6) || (Ndiv > 12))
+		return false;
+
+	return true;
+}
+
 /* The size in bits of the pll divide multiplied by 10
  * to allow rounding later */
 #define FIXED_PLL_SIZE ((1 << 24) * 10)
···
 	return 0;
 }
 
-static int wm8960_set_dai_pll(struct snd_soc_dai *codec_dai, int pll_id,
-		int source, unsigned int freq_in, unsigned int freq_out)
+static int wm8960_set_pll(struct snd_soc_codec *codec,
+		unsigned int freq_in, unsigned int freq_out)
 {
-	struct snd_soc_codec *codec = codec_dai->codec;
 	u16 reg;
 	static struct _pll_div pll_div;
 	int ret;
···
 	snd_soc_update_bits(codec, WM8960_CLOCK1, 0x1, 0x1);
 
 	return 0;
+}
+
+static int wm8960_set_dai_pll(struct snd_soc_dai *codec_dai, int pll_id,
+		int source, unsigned int freq_in, unsigned int freq_out)
+{
+	struct snd_soc_codec *codec = codec_dai->codec;
+	struct wm8960_priv *wm8960 = snd_soc_codec_get_drvdata(codec);
+
+	wm8960->freq_in = freq_in;
+
+	if (pll_id == WM8960_SYSCLK_AUTO)
+		return 0;
+
+	return wm8960_set_pll(codec, freq_in, freq_out);
 }
 
 static int wm8960_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
···
 		snd_soc_update_bits(codec, WM8960_CLOCK1,
 					0x1, WM8960_SYSCLK_PLL);
 		break;
+	case WM8960_SYSCLK_AUTO:
+		break;
 	default:
 		return -EINVAL;
 	}
 
 	wm8960->sysclk = freq;
+	wm8960->clk_id = clk_id;
 
 	return 0;
 }
···
 
 static const struct snd_soc_dai_ops wm8960_dai_ops = {
 	.hw_params = wm8960_hw_params,
+	.hw_free = wm8960_hw_free,
 	.digital_mute = wm8960_mute,
 	.set_fmt = wm8960_set_dai_fmt,
 	.set_clkdiv = wm8960_set_dai_clkdiv,

sound/soc/codecs/wm8960.h

···
 
 #define WM8960_SYSCLK_MCLK		(0 << 0)
 #define WM8960_SYSCLK_PLL		(1 << 0)
+#define WM8960_SYSCLK_AUTO		(2 << 0)
 
 #define WM8960_DAC_DIV_1		(0 << 3)
 #define WM8960_DAC_DIV_1_5		(1 << 3)