[PATCH] ASoC: cs42xx8: Fix MFREQ selection issue for async mode

From: Shengjiu Wang
Date: Tue Jul 16 2019 - 05:45:47 EST


When sample rate of TX is different with sample rate of RX in
async mode, the MFreq selection will be wrong.

For example, sysclk = 24.576MHz, TX rate = 96000Hz, RX rate = 48000Hz.
Then ratio of TX = 256, ratio of RX = 512, For MFreq is shared by TX
and RX instance, the correct value of MFreq is 2 for both TX and RX.

But original method will cause MFreq = 0 for TX, MFreq = 2 for RX.
If TX is started after RX, RX will be impacted, RX work abnormal with
MFreq = 0.

This patch is to select proper MFreq value according to TX rate and
RX rate.

Fixes: 0c516b4ff85c ("ASoC: cs42xx8: Add codec driver support for CS42448/CS42888")
Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
Link: https://lore.kernel.org/r/20190716094547.46787-1-shengjiu.wang@xxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/codecs/cs42xx8.c | 116 +++++++++++++++++++++++++++++++------
1 file changed, 97 insertions(+), 19 deletions(-)

diff --git a/sound/soc/codecs/cs42xx8.c b/sound/soc/codecs/cs42xx8.c
index 6203f54d9f25..5b049fcdba20 100644
--- a/sound/soc/codecs/cs42xx8.c
+++ b/sound/soc/codecs/cs42xx8.c
@@ -47,6 +47,7 @@ struct cs42xx8_priv {
unsigned long sysclk;
u32 tx_channels;
struct gpio_desc *gpiod_reset;
+ u32 rate[2];
};

/* -127.5dB to 0dB with step of 0.5dB */
@@ -176,21 +177,27 @@ static const struct snd_soc_dapm_route cs42xx8_adc3_dapm_routes[] = {
};

struct cs42xx8_ratios {
- unsigned int ratio;
- unsigned char speed;
- unsigned char mclk;
+ unsigned int mfreq;
+ unsigned int min_mclk;
+ unsigned int max_mclk;
+ unsigned int ratio[3];
};

+/*
+ * According to reference mannual, define the cs42xx8_ratio struct
+ * MFreq2 | MFreq1 | MFreq0 | Description | SSM | DSM | QSM |
+ * 0 | 0 | 0 |1.029MHz to 12.8MHz | 256 | 128 | 64 |
+ * 0 | 0 | 1 |1.536MHz to 19.2MHz | 384 | 192 | 96 |
+ * 0 | 1 | 0 |2.048MHz to 25.6MHz | 512 | 256 | 128 |
+ * 0 | 1 | 1 |3.072MHz to 38.4MHz | 768 | 384 | 192 |
+ * 1 | x | x |4.096MHz to 51.2MHz |1024 | 512 | 256 |
+ */
static const struct cs42xx8_ratios cs42xx8_ratios[] = {
- { 64, CS42XX8_FM_QUAD, CS42XX8_FUNCMOD_MFREQ_256(4) },
- { 96, CS42XX8_FM_QUAD, CS42XX8_FUNCMOD_MFREQ_384(4) },
- { 128, CS42XX8_FM_QUAD, CS42XX8_FUNCMOD_MFREQ_512(4) },
- { 192, CS42XX8_FM_QUAD, CS42XX8_FUNCMOD_MFREQ_768(4) },
- { 256, CS42XX8_FM_SINGLE, CS42XX8_FUNCMOD_MFREQ_256(1) },
- { 384, CS42XX8_FM_SINGLE, CS42XX8_FUNCMOD_MFREQ_384(1) },
- { 512, CS42XX8_FM_SINGLE, CS42XX8_FUNCMOD_MFREQ_512(1) },
- { 768, CS42XX8_FM_SINGLE, CS42XX8_FUNCMOD_MFREQ_768(1) },
- { 1024, CS42XX8_FM_SINGLE, CS42XX8_FUNCMOD_MFREQ_1024(1) }
+ { 0, 1029000, 12800000, {256, 128, 64} },
+ { 2, 1536000, 19200000, {384, 192, 96} },
+ { 4, 2048000, 25600000, {512, 256, 128} },
+ { 6, 3072000, 38400000, {768, 384, 192} },
+ { 8, 4096000, 51200000, {1024, 512, 256} },
};

static int cs42xx8_set_dai_sysclk(struct snd_soc_dai *codec_dai,
@@ -257,14 +264,68 @@ static int cs42xx8_hw_params(struct snd_pcm_substream *substream,
struct snd_soc_component *component = dai->component;
struct cs42xx8_priv *cs42xx8 = snd_soc_component_get_drvdata(component);
bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
- u32 ratio = cs42xx8->sysclk / params_rate(params);
- u32 i, fm, val, mask;
+ u32 ratio[2];
+ u32 rate[2];
+ u32 fm[2];
+ u32 i, val, mask;
+ bool condition1, condition2;

if (tx)
cs42xx8->tx_channels = params_channels(params);

+ rate[tx] = params_rate(params);
+ rate[!tx] = cs42xx8->rate[!tx];
+
+ ratio[tx] = rate[tx] > 0 ? cs42xx8->sysclk / rate[tx] : 0;
+ ratio[!tx] = rate[!tx] > 0 ? cs42xx8->sysclk / rate[!tx] : 0;
+
+ /* Get functional mode for tx and rx according to rate */
+ for (i = 0; i < 2; i++) {
+ if (cs42xx8->slave_mode) {
+ fm[i] = CS42XX8_FM_AUTO;
+ } else {
+ if (rate[i] < 50000) {
+ fm[i] = CS42XX8_FM_SINGLE;
+ } else if (rate[i] > 50000 && rate[i] < 100000) {
+ fm[i] = CS42XX8_FM_DOUBLE;
+ } else if (rate[i] > 100000 && rate[i] < 200000) {
+ fm[i] = CS42XX8_FM_QUAD;
+ } else {
+ dev_err(component->dev,
+ "unsupported sample rate\n");
+ return -EINVAL;
+ }
+ }
+ }
+
for (i = 0; i < ARRAY_SIZE(cs42xx8_ratios); i++) {
- if (cs42xx8_ratios[i].ratio == ratio)
+ /* Is the ratio[tx] valid ? */
+ condition1 = ((fm[tx] == CS42XX8_FM_AUTO) ?
+ (cs42xx8_ratios[i].ratio[0] == ratio[tx] ||
+ cs42xx8_ratios[i].ratio[1] == ratio[tx] ||
+ cs42xx8_ratios[i].ratio[2] == ratio[tx]) :
+ (cs42xx8_ratios[i].ratio[fm[tx]] == ratio[tx])) &&
+ cs42xx8->sysclk >= cs42xx8_ratios[i].min_mclk &&
+ cs42xx8->sysclk <= cs42xx8_ratios[i].max_mclk;
+
+ if (!ratio[tx])
+ condition1 = true;
+
+ /* Is the ratio[!tx] valid ? */
+ condition2 = ((fm[!tx] == CS42XX8_FM_AUTO) ?
+ (cs42xx8_ratios[i].ratio[0] == ratio[!tx] ||
+ cs42xx8_ratios[i].ratio[1] == ratio[!tx] ||
+ cs42xx8_ratios[i].ratio[2] == ratio[!tx]) :
+ (cs42xx8_ratios[i].ratio[fm[!tx]] == ratio[!tx]));
+
+ if (!ratio[!tx])
+ condition2 = true;
+
+ /*
+ * Both ratio[tx] and ratio[!tx] is valid, then we get
+ * a proper MFreq.
+ */
+ if (condition1 && condition2)
break;
}

@@ -273,15 +334,31 @@ static int cs42xx8_hw_params(struct snd_pcm_substream *substream,
return -EINVAL;
}

- mask = CS42XX8_FUNCMOD_MFREQ_MASK;
- val = cs42xx8_ratios[i].mclk;
+ cs42xx8->rate[tx] = params_rate(params);

- fm = cs42xx8->slave_mode ? CS42XX8_FM_AUTO : cs42xx8_ratios[i].speed;
+ mask = CS42XX8_FUNCMOD_MFREQ_MASK;
+ val = cs42xx8_ratios[i].mfreq;

regmap_update_bits(cs42xx8->regmap, CS42XX8_FUNCMOD,
CS42XX8_FUNCMOD_xC_FM_MASK(tx) | mask,
- CS42XX8_FUNCMOD_xC_FM(tx, fm) | val);
+ CS42XX8_FUNCMOD_xC_FM(tx, fm[tx]) | val);
+
+ return 0;
+}
+
+static int cs42xx8_hw_free(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct snd_soc_component *component = dai->component;
+ struct cs42xx8_priv *cs42xx8 = snd_soc_component_get_drvdata(component);
+ bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;

+ /* Clear stored rate */
+ cs42xx8->rate[tx] = 0;
+
+ regmap_update_bits(cs42xx8->regmap, CS42XX8_FUNCMOD,
+ CS42XX8_FUNCMOD_xC_FM_MASK(tx),
+ CS42XX8_FUNCMOD_xC_FM(tx, CS42XX8_FM_AUTO));
return 0;
}

@@ -302,6 +379,7 @@ static const struct snd_soc_dai_ops cs42xx8_dai_ops = {
.set_fmt = cs42xx8_set_dai_fmt,
.set_sysclk = cs42xx8_set_dai_sysclk,
.hw_params = cs42xx8_hw_params,
+ .hw_free = cs42xx8_hw_free,
.digital_mute = cs42xx8_digital_mute,
};

--
2.20.1