[PATCH] ASoC: qcom: lpass-cpu: support full duplex operation

[Srinivas Kandagatla]

From: Takahide Higuchi <takahidehiguchi at gmail.com>

This patch fixes a bug where playback on bidirectional I2S interface stops
when we start recording on the same interface.

We use regmap_update_bits instead of regmap_write so that we will not clear
SPKEN and SPKMODE bits when we start/stop recording.

Signed-off-by: Takahide Higuchi <takahidehiguchi at gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla at linaro.org>
---
 sound/soc/qcom/lpass-apq8016.c   |  2 ++
 sound/soc/qcom/lpass-cpu.c       | 24 ++++++++++++++++++------
 sound/soc/qcom/lpass-lpaif-reg.h |  2 +-
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/sound/soc/qcom/lpass-apq8016.c b/sound/soc/qcom/lpass-apq8016.c
index 6575da549237..85079c697faa 100644
--- a/sound/soc/qcom/lpass-apq8016.c
+++ b/sound/soc/qcom/lpass-apq8016.c
@@ -121,6 +121,8 @@ static struct snd_soc_dai_driver apq8016_lpass_cpu_dai_driver[] = {
 		},
 		.probe	= &asoc_qcom_lpass_cpu_dai_probe,
 		.ops    = &asoc_qcom_lpass_cpu_dai_ops,
+		.symmetric_samplebits   = 1,
+		.symmetric_rates        = 1,
 	},
 };
 
diff --git a/sound/soc/qcom/lpass-cpu.c b/sound/soc/qcom/lpass-cpu.c
index dbce7e92baf3..dc8acb380b6f 100644
--- a/sound/soc/qcom/lpass-cpu.c
+++ b/sound/soc/qcom/lpass-cpu.c
@@ -72,6 +72,7 @@ static int lpass_cpu_daiops_hw_params(struct snd_pcm_substream *substream,
 	snd_pcm_format_t format = params_format(params);
 	unsigned int channels = params_channels(params);
 	unsigned int rate = params_rate(params);
+	unsigned int mask;
 	unsigned int regval;
 	int bitwidth, ret;
 
@@ -81,6 +82,9 @@ static int lpass_cpu_daiops_hw_params(struct snd_pcm_substream *substream,
 		return bitwidth;
 	}
 
+	mask   = LPAIF_I2SCTL_LOOPBACK_MASK |
+			LPAIF_I2SCTL_WSSRC_MASK |
+			LPAIF_I2SCTL_BITWIDTH_MASK;
 	regval = LPAIF_I2SCTL_LOOPBACK_DISABLE |
 			LPAIF_I2SCTL_WSSRC_INTERNAL;
 
@@ -100,6 +104,7 @@ static int lpass_cpu_daiops_hw_params(struct snd_pcm_substream *substream,
 	}
 
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		mask   |= LPAIF_I2SCTL_SPKMODE_MASK | LPAIF_I2SCTL_SPKMONO_MASK;
 		switch (channels) {
 		case 1:
 			regval |= LPAIF_I2SCTL_SPKMODE_SD0;
@@ -127,6 +132,7 @@ static int lpass_cpu_daiops_hw_params(struct snd_pcm_substream *substream,
 			return -EINVAL;
 		}
 	} else {
+		mask   |= LPAIF_I2SCTL_MICMODE_MASK | LPAIF_I2SCTL_MICMONO_MASK;
 		switch (channels) {
 		case 1:
 			regval |= LPAIF_I2SCTL_MICMODE_SD0;
@@ -155,9 +161,9 @@ static int lpass_cpu_daiops_hw_params(struct snd_pcm_substream *substream,
 		}
 	}
 
-	ret = regmap_write(drvdata->lpaif_map,
-			   LPAIF_I2SCTL_REG(drvdata->variant, dai->driver->id),
-			   regval);
+	ret = regmap_update_bits(drvdata->lpaif_map,
+			 LPAIF_I2SCTL_REG(drvdata->variant, dai->driver->id),
+			 mask, regval);
 	if (ret) {
 		dev_err(dai->dev, "error writing to i2sctl reg: %d\n", ret);
 		return ret;
@@ -178,11 +184,17 @@ static int lpass_cpu_daiops_hw_free(struct snd_pcm_substream *substream,
 		struct snd_soc_dai *dai)
 {
 	struct lpass_data *drvdata = snd_soc_dai_get_drvdata(dai);
+	unsigned int mask;
 	int ret;
 
-	ret = regmap_write(drvdata->lpaif_map,
-			   LPAIF_I2SCTL_REG(drvdata->variant, dai->driver->id),
-			   0);
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		mask   = LPAIF_I2SCTL_SPKMODE_MASK;
+	else
+		mask   = LPAIF_I2SCTL_MICMODE_MASK;
+
+	ret = regmap_update_bits(drvdata->lpaif_map,
+			 LPAIF_I2SCTL_REG(drvdata->variant, dai->driver->id),
+			 mask, 0);
 	if (ret)
 		dev_err(dai->dev, "error writing to i2sctl reg: %d\n", ret);
 
diff --git a/sound/soc/qcom/lpass-lpaif-reg.h b/sound/soc/qcom/lpass-lpaif-reg.h
index 3d74ae123e9d..7a2b9cf99976 100644
--- a/sound/soc/qcom/lpass-lpaif-reg.h
+++ b/sound/soc/qcom/lpass-lpaif-reg.h
@@ -56,7 +56,7 @@
 #define LPAIF_I2SCTL_MICMODE_6CH	(7 << LPAIF_I2SCTL_MICMODE_SHIFT)
 #define LPAIF_I2SCTL_MICMODE_8CH	(8 << LPAIF_I2SCTL_MICMODE_SHIFT)
 
-#define LPAIF_I2SCTL_MIMONO_MASK	GENMASK(3, 3)
+#define LPAIF_I2SCTL_MICMONO_MASK	GENMASK(3, 3)
 #define LPAIF_I2SCTL_MICMONO_SHIFT	3
 #define LPAIF_I2SCTL_MICMONO_STEREO	(0 << LPAIF_I2SCTL_MICMONO_SHIFT)
 #define LPAIF_I2SCTL_MICMONO_MONO	(1 << LPAIF_I2SCTL_MICMONO_SHIFT)
-- 
2.21.0