[alsa-devel] [PATCH 1/2] ASoC: tlv320aic31xx: Fix 24bit samples with I2S format and 12MHz mclk

Jyri Sarha jsarha at ti.com
Wed Sep 3 14:52:33 CEST 2014


I2S format requires bitclock to have an exact amount of cycles in a
frame for audio to work cleanly. With dsp formats that is not so
important.

Updates aic31xx_setup_pll() to look for a line in aic31xx_divs table
that produces the best match for the bitclock and adds lines to
aic31xx_divs for 12MHz mclk and 24bit samples.

Signed-off-by: Jyri Sarha <jsarha at ti.com>
---
 sound/soc/codecs/tlv320aic31xx.c |   51 +++++++++++++++++++++++++++++---------
 1 file changed, 39 insertions(+), 12 deletions(-)

diff --git a/sound/soc/codecs/tlv320aic31xx.c b/sound/soc/codecs/tlv320aic31xx.c
index 0f64c78..aea9e1f 100644
--- a/sound/soc/codecs/tlv320aic31xx.c
+++ b/sound/soc/codecs/tlv320aic31xx.c
@@ -189,46 +189,57 @@ static const struct aic31xx_rate_divs aic31xx_divs[] = {
 	/* mclk      rate  pll: p  j	 d     dosr ndac mdac  aors nadc madc */
 	/* 8k rate */
 	{12000000,   8000,	1, 8, 1920,	128,  48,  2,	128,  48,  2},
+	{12000000,   8000,	1, 8, 1920,	128,  32,  3,	128,  32,  3},
 	{24000000,   8000,	2, 8, 1920,	128,  48,  2,	128,  48,  2},
 	{25000000,   8000,	2, 7, 8643,	128,  48,  2,	128,  48,  2},
 	/* 11.025k rate */
 	{12000000,  11025,	1, 7, 5264,	128,  32,  2,	128,  32,  2},
+	{12000000,  11025,	1, 8, 4672,	128,  24,  3,	128,  24,  3},
 	{24000000,  11025,	2, 7, 5264,	128,  32,  2,	128,  32,  2},
 	{25000000,  11025,	2, 7, 2253,	128,  32,  2,	128,  32,  2},
 	/* 16k rate */
 	{12000000,  16000,	1, 8, 1920,	128,  24,  2,	128,  24,  2},
+	{12000000,  16000,	1, 8, 1920,	128,  16,  3,	128,  16,  3},
 	{24000000,  16000,	2, 8, 1920,	128,  24,  2,	128,  24,  2},
 	{25000000,  16000,	2, 7, 8643,	128,  24,  2,	128,  24,  2},
 	/* 22.05k rate */
 	{12000000,  22050,	1, 7, 5264,	128,  16,  2,	128,  16,  2},
+	{12000000,  22050,	1, 8, 4672,	128,  12,  3,	128,  12,  3},
 	{24000000,  22050,	2, 7, 5264,	128,  16,  2,	128,  16,  2},
 	{25000000,  22050,	2, 7, 2253,	128,  16,  2,	128,  16,  2},
 	/* 32k rate */
 	{12000000,  32000,	1, 8, 1920,	128,  12,  2,	128,  12,  2},
+	{12000000,  32000,	1, 8, 1920,	128,   8,  3,	128,   8,  3},
 	{24000000,  32000,	2, 8, 1920,	128,  12,  2,	128,  12,  2},
 	{25000000,  32000,	2, 7, 8643,	128,  12,  2,	128,  12,  2},
 	/* 44.1k rate */
 	{12000000,  44100,	1, 7, 5264,	128,   8,  2,	128,   8,  2},
+	{12000000,  44100,	1, 8, 4672,	128,   6,  3,	128,   6,  3},
 	{24000000,  44100,	2, 7, 5264,	128,   8,  2,	128,   8,  2},
 	{25000000,  44100,	2, 7, 2253,	128,   8,  2,	128,   8,  2},
 	/* 48k rate */
 	{12000000,  48000,	1, 8, 1920,	128,   8,  2,	128,   8,  2},
+	{12000000,  48000,	1, 7, 6800,	 96,   5,  4,	 96,   5,  4},
 	{24000000,  48000,	2, 8, 1920,	128,   8,  2,	128,   8,  2},
 	{25000000,  48000,	2, 7, 8643,	128,   8,  2,	128,   8,  2},
 	/* 88.2k rate */
 	{12000000,  88200,	1, 7, 5264,	 64,   8,  2,	 64,   8,  2},
+	{12000000,  88200,	1, 8, 4672,	 64,   6,  3,	 64,   6,  3},
 	{24000000,  88200,	2, 7, 5264,	 64,   8,  2,	 64,   8,  2},
 	{25000000,  88200,	2, 7, 2253,	 64,   8,  2,	 64,   8,  2},
 	/* 96k rate */
 	{12000000,  96000,	1, 8, 1920,	 64,   8,  2,	 64,   8,  2},
+	{12000000,  96000,	1, 7, 6800,	 48,   5,  4,	 48,   5,  4},
 	{24000000,  96000,	2, 8, 1920,	 64,   8,  2,	 64,   8,  2},
 	{25000000,  96000,	2, 7, 8643,	 64,   8,  2,	 64,   8,  2},
 	/* 176.4k rate */
 	{12000000, 176400,	1, 7, 5264,	 32,   8,  2,	 32,   8,  2},
+	{12000000, 176400,	1, 8, 4672,	 32,   6,  3,	 32,   6,  3},
 	{24000000, 176400,	2, 7, 5264,	 32,   8,  2,	 32,   8,  2},
 	{25000000, 176400,	2, 7, 2253,	 32,   8,  2,	 32,   8,  2},
 	/* 192k rate */
 	{12000000, 192000,	1, 8, 1920,	 32,   8,  2,	 32,   8,  2},
+	{12000000, 192000,	1, 7, 6800,	 24,   5,  4,	 24,   5,  4},
 	{24000000, 192000,	2, 8, 1920,	 32,   8,  2,	 32,   8,  2},
 	{25000000, 192000,	2, 7, 8643,	 32,   8,  2,	 32,   8,  2},
 };
@@ -680,7 +691,9 @@ static int aic31xx_setup_pll(struct snd_soc_codec *codec,
 			     struct snd_pcm_hw_params *params)
 {
 	struct aic31xx_priv *aic31xx = snd_soc_codec_get_drvdata(codec);
+	int bclk_score = snd_soc_params_to_frame_size(params);
 	int bclk_n = 0;
+	int match = -1;
 	int i;
 
 	/* Use PLL as CODEC_CLKIN and DAC_CLK as BDIV_CLKIN */
@@ -691,15 +704,37 @@ static int aic31xx_setup_pll(struct snd_soc_codec *codec,
 
 	for (i = 0; i < ARRAY_SIZE(aic31xx_divs); i++) {
 		if (aic31xx_divs[i].rate == params_rate(params) &&
-		    aic31xx_divs[i].mclk == aic31xx->sysclk)
-			break;
+		    aic31xx_divs[i].mclk == aic31xx->sysclk) {
+			int s =	(aic31xx_divs[i].dosr * aic31xx_divs[i].mdac) %
+				snd_soc_params_to_frame_size(params);
+			int bn = (aic31xx_divs[i].dosr * aic31xx_divs[i].mdac) /
+				snd_soc_params_to_frame_size(params);
+			if (s < bclk_score && bn > 0) {
+				match = i;
+				bclk_n = bn;
+				bclk_score = s;
+			}
+		}
 	}
 
-	if (i == ARRAY_SIZE(aic31xx_divs)) {
-		dev_err(codec->dev, "%s: Sampling rate %u not supported\n",
+	if (match == -1) {
+		dev_err(codec->dev,
+			"%s: Sample rate (%u) and format not supported\n",
 			__func__, params_rate(params));
+		/* See bellow for details how fix this. */
 		return -EINVAL;
 	}
+	if (bclk_score != 0) {
+		dev_warn(codec->dev, "Can not produce exact bitclock");
+		/* This is fine if using dsp format, but if using i2s
+		   there may be trouble. To fix the issue edit the
+		   aic31xx_divs table for your mclk and sample
+		   rate. Details can be found from:
+		   http://www.ti.com/lit/ds/symlink/tlv320aic3100.pdf
+		   Section: 5.6 CLOCK Generation and PLL
+		*/
+	}
+	i = match;
 
 	/* PLL configuration */
 	snd_soc_update_bits(codec, AIC31XX_PLLPR, AIC31XX_PLL_MASK,
@@ -729,14 +764,6 @@ static int aic31xx_setup_pll(struct snd_soc_codec *codec,
 	snd_soc_write(codec, AIC31XX_AOSR, aic31xx_divs[i].aosr);
 
 	/* Bit clock divider configuration. */
-	bclk_n = (aic31xx_divs[i].dosr * aic31xx_divs[i].mdac)
-		/ snd_soc_params_to_frame_size(params);
-	if (bclk_n == 0) {
-		dev_err(codec->dev, "%s: Not enough BLCK bandwidth\n",
-			__func__);
-		return -EINVAL;
-	}
-
 	snd_soc_update_bits(codec, AIC31XX_BCLKN,
 			    AIC31XX_PLL_MASK, bclk_n);
 
-- 
1.7.9.5



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