[PATCH] ASoC: fsl_xcvr: Improve suspend/resume flow in fsl_xcvr_trigger()

[Chancel Liu]

In the current flow all interrupts are disabled in runtime suspend
phase. However interrupts enablement only exists in fsl_xcvr_prepare().
After resume fsl_xcvr_prepare() may not be called so it will cause all
interrupts still disabled even if resume from suspend. Interrupts
should be explictily enabled after resume.

Also, DPATH reset setting only exists in fsl_xcvr_prepare(). After
resume from suspend DPATH should be reset otherwise there'll be channel
swap issue.

Signed-off-by: Chancel Liu <chancel.liu at nxp.com>
---
 sound/soc/fsl/fsl_xcvr.c | 43 +++++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 20 deletions(-)

diff --git a/sound/soc/fsl/fsl_xcvr.c b/sound/soc/fsl/fsl_xcvr.c
index 337da46a2f90..bf9a4e90978e 100644
--- a/sound/soc/fsl/fsl_xcvr.c
+++ b/sound/soc/fsl/fsl_xcvr.c
@@ -529,16 +529,6 @@ static int fsl_xcvr_prepare(struct snd_pcm_substream *substream,
 		break;
 	}
 
-	ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_IER0,
-				 FSL_XCVR_IRQ_EARC_ALL, FSL_XCVR_IRQ_EARC_ALL);
-	if (ret < 0) {
-		dev_err(dai->dev, "Error while setting IER0: %d\n", ret);
-		return ret;
-	}
-
-	/* set DPATH RESET */
-	m_ctl |= FSL_XCVR_EXT_CTRL_DPTH_RESET(tx);
-	v_ctl |= FSL_XCVR_EXT_CTRL_DPTH_RESET(tx);
 	ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_CTRL, m_ctl, v_ctl);
 	if (ret < 0) {
 		dev_err(dai->dev, "Error while setting EXT_CTRL: %d\n", ret);
@@ -679,6 +669,15 @@ static int fsl_xcvr_trigger(struct snd_pcm_substream *substream, int cmd,
 	case SNDRV_PCM_TRIGGER_START:
 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		/* set DPATH RESET */
+		ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_CTRL,
+					 FSL_XCVR_EXT_CTRL_DPTH_RESET(tx),
+					 FSL_XCVR_EXT_CTRL_DPTH_RESET(tx));
+		if (ret < 0) {
+			dev_err(dai->dev, "Failed to set DPATH RESET: %d\n", ret);
+			return ret;
+		}
+
 		if (tx) {
 			switch (xcvr->mode) {
 			case FSL_XCVR_MODE_EARC:
@@ -711,6 +710,13 @@ static int fsl_xcvr_trigger(struct snd_pcm_substream *substream, int cmd,
 			return ret;
 		}
 
+		ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_IER0,
+					 FSL_XCVR_IRQ_EARC_ALL, FSL_XCVR_IRQ_EARC_ALL);
+		if (ret < 0) {
+			dev_err(dai->dev, "Error while setting IER0: %d\n", ret);
+			return ret;
+		}
+
 		/* clear DPATH RESET */
 		ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_CTRL,
 					 FSL_XCVR_EXT_CTRL_DPTH_RESET(tx),
@@ -733,6 +739,13 @@ static int fsl_xcvr_trigger(struct snd_pcm_substream *substream, int cmd,
 			return ret;
 		}
 
+		ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_IER0,
+					 FSL_XCVR_IRQ_EARC_ALL, 0);
+		if (ret < 0) {
+			dev_err(dai->dev, "Failed to clear IER0: %d\n", ret);
+			return ret;
+		}
+
 		if (tx) {
 			switch (xcvr->mode) {
 			case FSL_XCVR_MODE_SPDIF:
@@ -1411,16 +1424,6 @@ static int fsl_xcvr_runtime_suspend(struct device *dev)
 	struct fsl_xcvr *xcvr = dev_get_drvdata(dev);
 	int ret;
 
-	/*
-	 * Clear interrupts, when streams starts or resumes after
-	 * suspend, interrupts are enabled in prepare(), so no need
-	 * to enable interrupts in resume().
-	 */
-	ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_IER0,
-				 FSL_XCVR_IRQ_EARC_ALL, 0);
-	if (ret < 0)
-		dev_err(dev, "Failed to clear IER0: %d\n", ret);
-
 	if (!xcvr->soc_data->spdif_only) {
 		/* Assert M0+ reset */
 		ret = regmap_update_bits(xcvr->regmap, FSL_XCVR_EXT_CTRL,
-- 
2.43.0