ASoC: pcm512x: Support mastering BCLK/LRCLK without using the PLL

Use register field names from the seemingly compatible PCM5242 datasheet,
as the PCM512x and PCM514x datasheets are severly lacking.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 425 insertions, 16 deletions

diff --git a/sound/soc/codecs/pcm512x.c b/sound/soc/codecs/pcm512x.c
index 874723c36d65..526e6b30cdde 100644
--- a/sound/soc/codecs/pcm512x.c
+++ b/sound/soc/codecs/pcm512x.c
@@ -23,6 +23,7 @@
 #include <linux/regulator/consumer.h>
 #include <sound/soc.h>
 #include <sound/soc-dapm.h>
+#include <sound/pcm_params.h>
 #include <sound/tlv.h>
 
 #include "pcm512x.h"
@@ -39,6 +40,7 @@ struct pcm512x_priv {
 	struct clk *sclk;
 	struct regulator_bulk_data supplies[PCM512x_NUM_SUPPLIES];
 	struct notifier_block supply_nb[PCM512x_NUM_SUPPLIES];
+	int fmt;
 };
 
 /*
@@ -69,6 +71,7 @@ static const struct reg_default pcm512x_reg_defaults[] = {
 	{ PCM512x_MUTE,              0x00 },
 	{ PCM512x_DSP,               0x00 },
 	{ PCM512x_PLL_REF,           0x00 },
+	{ PCM512x_DAC_REF,           0x00 },
 	{ PCM512x_DAC_ROUTING,       0x11 },
 	{ PCM512x_DSP_PROGRAM,       0x01 },
 	{ PCM512x_CLKDET,            0x00 },
@@ -87,6 +90,18 @@ static const struct reg_default pcm512x_reg_defaults[] = {
 	{ PCM512x_ANALOG_GAIN_BOOST, 0x00 },
 	{ PCM512x_VCOM_CTRL_1,       0x00 },
 	{ PCM512x_VCOM_CTRL_2,       0x01 },
+	{ PCM512x_BCLK_LRCLK_CFG,    0x00 },
+	{ PCM512x_MASTER_MODE,       0x7c },
+	{ PCM512x_SYNCHRONIZE,       0x10 },
+	{ PCM512x_DSP_CLKDIV,        0x00 },
+	{ PCM512x_DAC_CLKDIV,        0x00 },
+	{ PCM512x_NCP_CLKDIV,        0x00 },
+	{ PCM512x_OSR_CLKDIV,        0x00 },
+	{ PCM512x_MASTER_CLKDIV_1,   0x00 },
+	{ PCM512x_MASTER_CLKDIV_2,   0x00 },
+	{ PCM512x_FS_SPEED_MODE,     0x00 },
+	{ PCM512x_IDAC_1,            0x01 },
+	{ PCM512x_IDAC_2,            0x00 },
 };
 
 static bool pcm512x_readable(struct device *dev, unsigned int reg)
@@ -103,6 +118,8 @@ static bool pcm512x_readable(struct device *dev, unsigned int reg)
 	case PCM512x_DSP_GPIO_INPUT:
 	case PCM512x_MASTER_MODE:
 	case PCM512x_PLL_REF:
+	case PCM512x_DAC_REF:
+	case PCM512x_SYNCHRONIZE:
 	case PCM512x_PLL_COEFF_0:
 	case PCM512x_PLL_COEFF_1:
 	case PCM512x_PLL_COEFF_2:
@@ -303,6 +320,94 @@ static const struct snd_soc_dapm_route pcm512x_dapm_routes[] = {
 	{ "OUTR", NULL, "DACR" },
 };
 
+static const u32 pcm512x_dai_rates[] = {
+	8000, 11025, 16000, 22050, 32000, 44100, 48000, 64000,
+	88200, 96000, 176400, 192000, 384000,
+};
+
+static const struct snd_pcm_hw_constraint_list constraints_slave = {
+	.count = ARRAY_SIZE(pcm512x_dai_rates),
+	.list  = pcm512x_dai_rates,
+};
+
+static int pcm512x_dai_startup_master(struct snd_pcm_substream *substream,
+				      struct snd_soc_dai *dai)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	struct pcm512x_priv *pcm512x = snd_soc_codec_get_drvdata(codec);
+	struct device *dev = dai->dev;
+	struct snd_pcm_hw_constraint_ratnums *constraints_no_pll;
+	struct snd_ratnum *rats_no_pll;
+
+	if (IS_ERR(pcm512x->sclk)) {
+		dev_err(dev, "Need SCLK for master mode: %ld\n",
+			PTR_ERR(pcm512x->sclk));
+		return PTR_ERR(pcm512x->sclk);
+	}
+
+	constraints_no_pll = devm_kzalloc(dev, sizeof(*constraints_no_pll),
+					  GFP_KERNEL);
+	if (!constraints_no_pll)
+		return -ENOMEM;
+	constraints_no_pll->nrats = 1;
+	rats_no_pll = devm_kzalloc(dev, sizeof(*rats_no_pll), GFP_KERNEL);
+	if (!rats_no_pll)
+		return -ENOMEM;
+	constraints_no_pll->rats = rats_no_pll;
+	rats_no_pll->num = clk_get_rate(pcm512x->sclk) / 64;
+	rats_no_pll->den_min = 1;
+	rats_no_pll->den_max = 128;
+	rats_no_pll->den_step = 1;
+
+	return snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
+					     SNDRV_PCM_HW_PARAM_RATE,
+					     constraints_no_pll);
+}
+
+static int pcm512x_dai_startup_slave(struct snd_pcm_substream *substream,
+				     struct snd_soc_dai *dai)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	struct pcm512x_priv *pcm512x = snd_soc_codec_get_drvdata(codec);
+	struct device *dev = dai->dev;
+	struct regmap *regmap = pcm512x->regmap;
+
+	if (IS_ERR(pcm512x->sclk)) {
+		dev_info(dev, "No SCLK, using BCLK: %ld\n",
+			 PTR_ERR(pcm512x->sclk));
+
+		/* Disable reporting of missing SCLK as an error */
+		regmap_update_bits(regmap, PCM512x_ERROR_DETECT,
+				   PCM512x_IDCH, PCM512x_IDCH);
+
+		/* Switch PLL input to BCLK */
+		regmap_update_bits(regmap, PCM512x_PLL_REF,
+				   PCM512x_SREF, PCM512x_SREF_BCK);
+	}
+
+	return snd_pcm_hw_constraint_list(substream->runtime, 0,
+					  SNDRV_PCM_HW_PARAM_RATE,
+					  &constraints_slave);
+}
+
+static int pcm512x_dai_startup(struct snd_pcm_substream *substream,
+			       struct snd_soc_dai *dai)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	struct pcm512x_priv *pcm512x = snd_soc_codec_get_drvdata(codec);
+
+	switch (pcm512x->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		return pcm512x_dai_startup_master(substream, dai);
+
+	case SND_SOC_DAIFMT_CBS_CFS:
+		return pcm512x_dai_startup_slave(substream, dai);
+
+	default:
+		return -EINVAL;
+	}
+}
+
 static int pcm512x_set_bias_level(struct snd_soc_codec *codec,
 				  enum snd_soc_bias_level level)
 {
@@ -340,17 +445,333 @@ static int pcm512x_set_bias_level(struct snd_soc_codec *codec,
 	return 0;
 }
 
+static int pcm512x_set_dividers(struct snd_soc_dai *dai,
+				struct snd_pcm_hw_params *params)
+{
+	struct device *dev = dai->dev;
+	struct snd_soc_codec *codec = dai->codec;
+	struct pcm512x_priv *pcm512x = snd_soc_codec_get_drvdata(codec);
+	unsigned long sck_rate;
+	unsigned long mck_rate;
+	unsigned long bclk_rate;
+	unsigned long sample_rate;
+	unsigned long osr_rate;
+	int bclk_div;
+	int lrclk_div;
+	int dsp_div;
+	int dac_div;
+	unsigned long dac_rate;
+	int ncp_div;
+	int osr_div;
+	unsigned long dac_mul;
+	unsigned long sck_mul;
+	int ret;
+	int idac;
+	int fssp;
+
+	lrclk_div = snd_soc_params_to_frame_size(params);
+	if (lrclk_div == 0) {
+		dev_err(dev, "No LRCLK?\n");
+		return -EINVAL;
+	}
+
+	sck_rate = clk_get_rate(pcm512x->sclk);
+	bclk_div = params->rate_den * 64 / lrclk_div;
+	bclk_rate = DIV_ROUND_CLOSEST(sck_rate, bclk_div);
+
+	mck_rate = sck_rate;
+
+	if (bclk_div > 128) {
+		dev_err(dev, "Failed to find BCLK divider\n");
+		return -EINVAL;
+	}
+
+	/* the actual rate */
+	sample_rate = sck_rate / bclk_div / lrclk_div;
+	osr_rate = 16 * sample_rate;
+
+	/* run DSP no faster than 50 MHz */
+	dsp_div = mck_rate > 50000000 ? 2 : 1;
+
+	/* run DAC no faster than 6144000 Hz */
+	dac_mul = 6144000 / osr_rate;
+	sck_mul = sck_rate / osr_rate;
+	for (; dac_mul; dac_mul--) {
+		if (!(sck_mul % dac_mul))
+			break;
+	}
+	if (!dac_mul) {
+		dev_err(dev, "Failed to find DAC rate\n");
+		return -EINVAL;
+	}
+
+	dac_rate = dac_mul * osr_rate;
+	dev_dbg(dev, "dac_rate %lu sample_rate %lu\n", dac_rate, sample_rate);
+
+	dac_div = DIV_ROUND_CLOSEST(sck_rate, dac_rate);
+	if (dac_div > 128) {
+		dev_err(dev, "Failed to find DAC divider\n");
+		return -EINVAL;
+	}
+
+	ncp_div = DIV_ROUND_CLOSEST(sck_rate / dac_div, 1536000);
+	if (ncp_div > 128 || sck_rate / dac_div / ncp_div > 2048000) {
+		/* run NCP no faster than 2048000 Hz, but why? */
+		ncp_div = DIV_ROUND_UP(sck_rate / dac_div, 2048000);
+		if (ncp_div > 128) {
+			dev_err(dev, "Failed to find NCP divider\n");
+			return -EINVAL;
+		}
+	}
+
+	osr_div = DIV_ROUND_CLOSEST(dac_rate, osr_rate);
+	if (osr_div > 128) {
+		dev_err(dev, "Failed to find OSR divider\n");
+		return -EINVAL;
+	}
+
+	idac = mck_rate / (dsp_div * sample_rate);
+
+	ret = regmap_write(pcm512x->regmap, PCM512x_DSP_CLKDIV, dsp_div - 1);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write DSP divider: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(pcm512x->regmap, PCM512x_DAC_CLKDIV, dac_div - 1);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write DAC divider: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(pcm512x->regmap, PCM512x_NCP_CLKDIV, ncp_div - 1);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write NCP divider: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(pcm512x->regmap, PCM512x_OSR_CLKDIV, osr_div - 1);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write OSR divider: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(pcm512x->regmap,
+			   PCM512x_MASTER_CLKDIV_1, bclk_div - 1);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write BCLK divider: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(pcm512x->regmap,
+			   PCM512x_MASTER_CLKDIV_2, lrclk_div - 1);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write LRCLK divider: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(pcm512x->regmap, PCM512x_IDAC_1, idac >> 8);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write IDAC msb divider: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_write(pcm512x->regmap, PCM512x_IDAC_2, idac & 0xff);
+	if (ret != 0) {
+		dev_err(dev, "Failed to write IDAC lsb divider: %d\n", ret);
+		return ret;
+	}
+
+	if (sample_rate <= 48000)
+		fssp = PCM512x_FSSP_48KHZ;
+	else if (sample_rate <= 96000)
+		fssp = PCM512x_FSSP_96KHZ;
+	else if (sample_rate <= 192000)
+		fssp = PCM512x_FSSP_192KHZ;
+	else
+		fssp = PCM512x_FSSP_384KHZ;
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_FS_SPEED_MODE,
+				 PCM512x_FSSP, fssp);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to set fs speed: %d\n", ret);
+		return ret;
+	}
+
+	dev_dbg(codec->dev, "DSP divider %d\n", dsp_div);
+	dev_dbg(codec->dev, "DAC divider %d\n", dac_div);
+	dev_dbg(codec->dev, "NCP divider %d\n", ncp_div);
+	dev_dbg(codec->dev, "OSR divider %d\n", osr_div);
+	dev_dbg(codec->dev, "BCK divider %d\n", bclk_div);
+	dev_dbg(codec->dev, "LRCK divider %d\n", lrclk_div);
+	dev_dbg(codec->dev, "IDAC %d\n", idac);
+	dev_dbg(codec->dev, "1<<FSSP %d\n", 1 << fssp);
+
+	return 0;
+}
+
+static int pcm512x_hw_params(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *params,
+			     struct snd_soc_dai *dai)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	struct pcm512x_priv *pcm512x = snd_soc_codec_get_drvdata(codec);
+	int alen;
+	int ret;
+
+	dev_dbg(codec->dev, "hw_params %u Hz, %u channels\n",
+		params_rate(params),
+		params_channels(params));
+
+	switch (snd_pcm_format_width(params_format(params))) {
+	case 16:
+		alen = PCM512x_ALEN_16;
+		break;
+	case 20:
+		alen = PCM512x_ALEN_20;
+		break;
+	case 24:
+		alen = PCM512x_ALEN_24;
+		break;
+	case 32:
+		alen = PCM512x_ALEN_32;
+		break;
+	default:
+		dev_err(codec->dev, "Bad frame size: %d\n",
+			snd_pcm_format_width(params_format(params)));
+		return -EINVAL;
+	}
+
+	switch (pcm512x->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBS_CFS:
+		ret = regmap_update_bits(pcm512x->regmap,
+					 PCM512x_BCLK_LRCLK_CFG,
+					 PCM512x_BCKP
+					 | PCM512x_BCKO | PCM512x_LRKO,
+					 0);
+		if (ret != 0) {
+			dev_err(codec->dev,
+				"Failed to enable slave mode: %d\n", ret);
+			return ret;
+		}
+
+		ret = regmap_update_bits(pcm512x->regmap, PCM512x_ERROR_DETECT,
+					 PCM512x_DCAS, 0);
+		if (ret != 0) {
+			dev_err(codec->dev,
+				"Failed to enable clock divider autoset: %d\n",
+				ret);
+			return ret;
+		}
+		return 0;
+	case SND_SOC_DAIFMT_CBM_CFM:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_I2S_1,
+				 PCM512x_ALEN, alen);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to set frame size: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_ERROR_DETECT,
+				 PCM512x_IDFS | PCM512x_IDBK
+				 | PCM512x_IDSK | PCM512x_IDCH
+				 | PCM512x_IDCM | PCM512x_DCAS
+				 | PCM512x_IPLK,
+				 PCM512x_IDFS | PCM512x_IDBK
+				 | PCM512x_IDSK | PCM512x_IDCH
+				 | PCM512x_DCAS | PCM512x_IPLK);
+	if (ret != 0) {
+		dev_err(codec->dev,
+			"Failed to ignore auto-clock failures: %d\n",
+			ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_PLL_EN,
+				 PCM512x_PLLE, 0);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to disable pll: %d\n", ret);
+		return ret;
+	}
+
+	ret = pcm512x_set_dividers(dai, params);
+	if (ret != 0)
+		return ret;
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_DAC_REF,
+				 PCM512x_SDAC, PCM512x_SDAC_SCK);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to set sck as dacref: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_BCLK_LRCLK_CFG,
+				 PCM512x_BCKP | PCM512x_BCKO | PCM512x_LRKO,
+				 PCM512x_BCKO | PCM512x_LRKO);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to enable clock output: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_MASTER_MODE,
+				 PCM512x_RLRK | PCM512x_RBCK,
+				 PCM512x_RLRK | PCM512x_RBCK);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to enable master mode: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_SYNCHRONIZE,
+				 PCM512x_RQSY, PCM512x_RQSY_HALT);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to halt clocks: %d\n", ret);
+		return ret;
+	}
+
+	ret = regmap_update_bits(pcm512x->regmap, PCM512x_SYNCHRONIZE,
+				 PCM512x_RQSY, PCM512x_RQSY_RESUME);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to resume clocks: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int pcm512x_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
+{
+	struct snd_soc_codec *codec = dai->codec;
+	struct pcm512x_priv *pcm512x = snd_soc_codec_get_drvdata(codec);
+
+	pcm512x->fmt = fmt;
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops pcm512x_dai_ops = {
+	.startup = pcm512x_dai_startup,
+	.hw_params = pcm512x_hw_params,
+	.set_fmt = pcm512x_set_fmt,
+};
+
 static struct snd_soc_dai_driver pcm512x_dai = {
 	.name = "pcm512x-hifi",
 	.playback = {
 		.stream_name = "Playback",
 		.channels_min = 2,
 		.channels_max = 2,
-		.rates = SNDRV_PCM_RATE_8000_192000,
+		.rates = SNDRV_PCM_RATE_CONTINUOUS,
+		.rate_min = 8000,
+		.rate_max = 384000,
 		.formats = SNDRV_PCM_FMTBIT_S16_LE |
 			   SNDRV_PCM_FMTBIT_S24_LE |
 			   SNDRV_PCM_FMTBIT_S32_LE
 	},
+	.ops = &pcm512x_dai_ops,
 };
 
 static struct snd_soc_codec_driver pcm512x_codec_driver = {
@@ -448,21 +869,9 @@ int pcm512x_probe(struct device *dev, struct regmap *regmap)
 	}
 
 	pcm512x->sclk = devm_clk_get(dev, NULL);
-	if (IS_ERR(pcm512x->sclk)) {
-		if (PTR_ERR(pcm512x->sclk) == -EPROBE_DEFER)
-			return -EPROBE_DEFER;
-
-		dev_info(dev, "No SCLK, using BCLK: %ld\n",
-			 PTR_ERR(pcm512x->sclk));
-
-		/* Disable reporting of missing SCLK as an error */
-		regmap_update_bits(regmap, PCM512x_ERROR_DETECT,
-				   PCM512x_IDCH, PCM512x_IDCH);
-
-		/* Switch PLL input to BCLK */
-		regmap_update_bits(regmap, PCM512x_PLL_REF,
-				   PCM512x_SREF, PCM512x_SREF);
-	} else {
+	if (PTR_ERR(pcm512x->sclk) == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+	if (!IS_ERR(pcm512x->sclk)) {
 		ret = clk_prepare_enable(pcm512x->sclk);
 		if (ret != 0) {
 			dev_err(dev, "Failed to enable SCLK: %d\n", ret);