MLK-17509: ASoC: imx-ak4458: Set MCLK freq as a function of FS

According to AK4458 RM the MCLK freq need to be set
externaly as function of LRCK frequency. Notice that
multiplier is twice the value shown in RM since SAI
MCLK must be at least double the BCLK.

Signed-off-by: Cosmin-Gabriel Samoila <cosmin.samoila@nxp.com>
Reviewed-by: Viorel Suman <viorel.suman@nxp.com>

1 files changed, 102 insertions, 14 deletions

diff --git a/sound/soc/fsl/imx-ak4458.c b/sound/soc/fsl/imx-ak4458.c
index 83d4a4e801a8..2c8c55dac408 100644
--- a/sound/soc/fsl/imx-ak4458.c
+++ b/sound/soc/fsl/imx-ak4458.c
@@ -17,23 +17,58 @@
 #include <linux/of_device.h>
 #include <linux/i2c.h>
 #include <linux/of_gpio.h>
+#include <linux/clk.h>
 #include <sound/soc.h>
 #include <sound/pcm_params.h>
 #include <sound/pcm.h>
 #include <sound/soc-dapm.h>
 
+#include "fsl_sai.h"
+
 struct imx_ak4458_data {
 	struct snd_soc_card card;
 	int num_codec_conf;
 	struct snd_soc_codec_conf *codec_conf;
 	bool tdm_mode;
 	int pdn_gpio;
+	unsigned long freq;
+	unsigned int slots;
+	unsigned int slot_width;
+};
+
+struct imx_ak4458_fs_mul {
+	unsigned int min;
+	unsigned int max;
+	unsigned int mul;
 };
 
 static struct snd_soc_dapm_widget imx_ak4458_dapm_widgets[] = {
 	SND_SOC_DAPM_LINE("Line Out", NULL),
 };
 
+static const struct imx_ak4458_fs_mul fs_mul[] = {
+	/*
+	 * Table 2      - mapping multiplier and speed mode
+	 * Tables 3 & 4 - mapping speed mode and LRCK fs
+	 */
+	{ .min = 8000,   .max = 48000,  .mul = 1024  }, /* Normal */
+	{ .min = 88200,  .max = 96000,  .mul = 512  }, /* Double */
+	{ .min = 176400, .max = 192000, .mul = 256  }, /* Quad */
+	{ .min = 384000, .max = 384000, .mul = 128   }, /* Oct */
+	{ .min = 768000, .max = 768000, .mul = 64   }, /* Hex */
+};
+
+static const struct imx_ak4458_fs_mul fs_mul_tdm[] = {
+	/*
+	 * Table 13	- Audio Interface Format
+	 * For TDM mode, MCLK should is set to
+	 * obtained from 2 * slots * slot_width
+	 */
+	{ .min = 128,	.max = 128,	.mul = 256  }, /* TDM128 */
+	{ .min = 256,	.max = 256,	.mul = 512  }, /* TDM256 */
+	{ .min = 512,	.max = 512,	.mul = 1024  }, /* TDM512 */
+};
+
 static const u32 ak4458_rates[] = {
 	8000, 16000, 32000,
 	48000, 96000, 192000,
@@ -53,6 +88,40 @@ static const u32 ak4458_channels_tdm[] = {
 	1, 2, 3, 4, 5, 6, 7, 8,
 };
 
+static unsigned long ak4458_get_mclk_rate(struct snd_pcm_substream *substream,
+					  struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct imx_ak4458_data *data = snd_soc_card_get_drvdata(rtd->card);
+	unsigned int rate = params_rate(params);
+	int i;
+	int mode;
+	unsigned int freq = data->freq;
+
+	if (data->tdm_mode) {
+		/* can be 128, 256 or 512 */
+		mode = data->slots * data->slot_width;
+
+		for (i = 0; i < ARRAY_SIZE(fs_mul_tdm); i++) {
+			/* min = max = slots * slots_width */
+			if (mode != fs_mul_tdm[i].min)
+				continue;
+			freq = rate * fs_mul_tdm[i].mul;
+			break;
+		}
+	} else {
+		for (i = 0; i < ARRAY_SIZE(fs_mul); i++) {
+			if (rate < fs_mul[i].min || rate > fs_mul[i].max)
+				continue;
+			/* rate is within min and max */
+			freq = rate * fs_mul[i].mul;
+			break;
+		}
+	}
+
+	return freq;
+}
+
 static int imx_aif_hw_params(struct snd_pcm_substream *substream,
 				struct snd_pcm_hw_params *params)
 {
@@ -64,6 +133,7 @@ static int imx_aif_hw_params(struct snd_pcm_substream *substream,
 	struct imx_ak4458_data *data = snd_soc_card_get_drvdata(card);
 	unsigned int channels = params_channels(params);
 	unsigned int fmt;
+	unsigned long mclk_freq;
 	int ret;
 	int i;
 
@@ -91,29 +161,37 @@ static int imx_aif_hw_params(struct snd_pcm_substream *substream,
 	}
 
 	if (data->tdm_mode) {
-		ret = snd_soc_dai_set_tdm_slot(cpu_dai,
-				       BIT(channels) - 1, BIT(channels) - 1,
-				       8, 32);
-		if (ret) {
-			dev_err(dev, "failed to set cpu dai tdm slot: %d\n", ret);
-			return ret;
-		}
+		data->slots = 8;
+		data->slot_width = 32;
 
 		ret = snd_soc_dai_set_tdm_slot(codec_dai,
 				       BIT(channels) - 1, BIT(channels) - 1,
-				       8, 32);
+				       data->slots, data->slot_width);
 		if (ret) {
 			dev_err(dev, "failed to set codec dai tdm slot: %d\n", ret);
 			return ret;
 		}
 	} else {
-		ret = snd_soc_dai_set_tdm_slot(cpu_dai,
+		data->slots = 2;
+		data->slot_width = params_physical_width(params);
+	}
+
+	ret = snd_soc_dai_set_tdm_slot(cpu_dai,
 				       BIT(channels) - 1, BIT(channels) - 1,
-				       2, params_physical_width(params));
-		if (ret) {
-			dev_err(dev, "failed to set cpu dai tdm slot: %d\n", ret);
-			return ret;
-		}
+				       data->slots, data->slot_width);
+	if (ret) {
+		dev_err(dev, "failed to set cpu dai tdm slot: %d\n", ret);
+		return ret;
+	}
+
+	/* set MCLK freq */
+	mclk_freq = ak4458_get_mclk_rate(substream, params);
+	ret = snd_soc_dai_set_sysclk(cpu_dai, FSL_SAI_CLK_MAST1, mclk_freq,
+				     SND_SOC_CLOCK_OUT);
+	if (ret < 0) {
+		dev_err(dev, "failed to set cpui dai mclk1 rate (%lu): %d\n",
+			mclk_freq, ret);
+		return ret;
 	}
 
 	return ret;
@@ -185,6 +263,7 @@ static int imx_ak4458_probe(struct platform_device *pdev)
 	struct imx_ak4458_data *priv;
 	struct device_node *cpu_np, *codec_np_0 = NULL, *codec_np_1 = NULL;
 	struct platform_device *cpu_pdev;
+	struct clk *mclk;
 	int ret;
 
 
@@ -267,6 +346,15 @@ static int imx_ak4458_probe(struct platform_device *pdev)
 		usleep_range(1000, 2000);
 	}
 
+	mclk = devm_clk_get(&cpu_pdev->dev, "mclk1");
+	if (IS_ERR(mclk)) {
+		ret = PTR_ERR(mclk);
+		dev_err(&pdev->dev, "failed to get DAI mclk1: %d\n", ret);
+		return -EINVAL;
+	}
+
+	priv->freq = clk_get_rate(mclk);
+
 	ret = snd_soc_of_parse_card_name(&priv->card, "model");
 	if (ret)
 		goto fail;