[PATCH] ASoC: sta32x: make power restoration transactional

[Pengpeng Hou]

sta32x_set_bias_level() enables the codec supplies, restores the
coefficient and register state, and then starts the watchdog. Register
access errors in the mute and coefficient helpers and the cache replay
are discarded, allowing DAPM to publish STANDBY for a partially restored
codec.

Propagate every operation in the local restore transaction, including
the final standby-state write. Start the watchdog only after that write
succeeds. On failure, hold reset, mark the cache dirty, disable the
supplies and report a cleanup failure while preserving the primary
error. The DAPM bias callback consumes the returned error independently
of component resume handling.

Fixes: 54dc6cabe684 ("ASoC: sta32x: preserve coefficient RAM")
Signed-off-by: Pengpeng Hou <pengpeng@xxxxxxxxxxx>
---
 sound/soc/codecs/sta32x.c | 101 +++++++++++++++++++++++++++++++++++-----------
 1 file changed, 77 insertions(+), 24 deletions(-)

diff --git a/sound/soc/codecs/sta32x.c b/sound/soc/codecs/sta32x.c
index d6de739212f92..3766db457b673 100644
--- a/sound/soc/codecs/sta32x.c
+++ b/sound/soc/codecs/sta32x.c
@@ -342,27 +342,48 @@ static int sta32x_sync_coef_shadow(struct snd_soc_component *component)
 {
 	struct sta32x_priv *sta32x = snd_soc_component_get_drvdata(component);
 	unsigned int cfud;
-	int i;
+	int i, ret;
 
 	/* preserve reserved bits in STA32X_CFUD */
-	regmap_read(sta32x->regmap, STA32X_CFUD, &cfud);
+	ret = regmap_read(sta32x->regmap, STA32X_CFUD, &cfud);
+	if (ret)
+		return ret;
+
 	cfud &= 0xf0;
 
 	for (i = 0; i < STA32X_COEF_COUNT; i++) {
-		regmap_write(sta32x->regmap, STA32X_CFADDR2, i);
-		regmap_write(sta32x->regmap, STA32X_B1CF1,
-			     (sta32x->coef_shadow[i] >> 16) & 0xff);
-		regmap_write(sta32x->regmap, STA32X_B1CF2,
-			     (sta32x->coef_shadow[i] >> 8) & 0xff);
-		regmap_write(sta32x->regmap, STA32X_B1CF3,
-			     (sta32x->coef_shadow[i]) & 0xff);
+		ret = regmap_write(sta32x->regmap, STA32X_CFADDR2, i);
+		if (ret)
+			return ret;
+
+		ret = regmap_write(sta32x->regmap, STA32X_B1CF1,
+				   (sta32x->coef_shadow[i] >> 16) & 0xff);
+		if (ret)
+			return ret;
+
+		ret = regmap_write(sta32x->regmap, STA32X_B1CF2,
+				   (sta32x->coef_shadow[i] >> 8) & 0xff);
+		if (ret)
+			return ret;
+
+		ret = regmap_write(sta32x->regmap, STA32X_B1CF3,
+				   sta32x->coef_shadow[i] & 0xff);
+		if (ret)
+			return ret;
+
 		/*
 		 * chip documentation does not say if the bits are
 		 * self-clearing, so do it explicitly
 		 */
-		regmap_write(sta32x->regmap, STA32X_CFUD, cfud);
-		regmap_write(sta32x->regmap, STA32X_CFUD, cfud | 0x01);
+		ret = regmap_write(sta32x->regmap, STA32X_CFUD, cfud);
+		if (ret)
+			return ret;
+
+		ret = regmap_write(sta32x->regmap, STA32X_CFUD, cfud | 0x01);
+		if (ret)
+			return ret;
 	}
+
 	return 0;
 }
 
@@ -370,15 +391,24 @@ static int sta32x_cache_sync(struct snd_soc_component *component)
 {
 	struct sta32x_priv *sta32x = snd_soc_component_get_drvdata(component);
 	unsigned int mute;
-	int rc;
+	int restore_ret, ret;
 
 	/* mute during register sync */
-	regmap_read(sta32x->regmap, STA32X_MMUTE, &mute);
-	regmap_write(sta32x->regmap, STA32X_MMUTE, mute | STA32X_MMUTE_MMUTE);
-	sta32x_sync_coef_shadow(component);
-	rc = regcache_sync(sta32x->regmap);
-	regmap_write(sta32x->regmap, STA32X_MMUTE, mute);
-	return rc;
+	ret = regmap_read(sta32x->regmap, STA32X_MMUTE, &mute);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(sta32x->regmap, STA32X_MMUTE,
+			   mute | STA32X_MMUTE_MMUTE);
+	if (ret)
+		return ret;
+
+	ret = sta32x_sync_coef_shadow(component);
+	if (!ret)
+		ret = regcache_sync(sta32x->regmap);
+
+	restore_ret = regmap_write(sta32x->regmap, STA32X_MMUTE, mute);
+	return ret ?: restore_ret;
 }
 
 /* work around ESD issue where sta32x resets and loses all configuration */
@@ -794,9 +824,9 @@ static int sta32x_startup_sequence(struct sta32x_priv *sta32x)
 static int sta32x_set_bias_level(struct snd_soc_component *component,
 				 enum snd_soc_bias_level level)
 {
-	int ret;
 	struct sta32x_priv *sta32x = snd_soc_component_get_drvdata(component);
 	struct snd_soc_dapm_context *dapm = snd_soc_component_to_dapm(component);
+	int cleanup_ret, ret;
 
 	dev_dbg(component->dev, "level = %d\n", level);
 	switch (level) {
@@ -820,15 +850,28 @@ static int sta32x_set_bias_level(struct snd_soc_component *component,
 				return ret;
 			}
 
-			sta32x_startup_sequence(sta32x);
-			sta32x_cache_sync(component);
+			ret = sta32x_startup_sequence(sta32x);
+			if (!ret)
+				ret = sta32x_cache_sync(component);
+			if (ret)
+				goto restore_failed;
+
+			ret = regmap_update_bits(sta32x->regmap, STA32X_CONFF,
+						 STA32X_CONFF_PWDN | STA32X_CONFF_EAPD,
+						 0);
+			if (ret)
+				goto restore_failed;
+
 			sta32x_watchdog_start(sta32x);
+			break;
 		}
 
 		/* Power down */
-		regmap_update_bits(sta32x->regmap, STA32X_CONFF,
-				   STA32X_CONFF_PWDN | STA32X_CONFF_EAPD,
-				   0);
+		ret = regmap_update_bits(sta32x->regmap, STA32X_CONFF,
+					 STA32X_CONFF_PWDN | STA32X_CONFF_EAPD,
+					 0);
+		if (ret)
+			return ret;
 
 		break;
 
@@ -846,6 +889,16 @@ static int sta32x_set_bias_level(struct snd_soc_component *component,
 		break;
 	}
 	return 0;
+
+restore_failed:
+	gpiod_set_value(sta32x->gpiod_nreset, 0);
+	regcache_mark_dirty(sta32x->regmap);
+	cleanup_ret = regulator_bulk_disable(ARRAY_SIZE(sta32x->supplies),
+					     sta32x->supplies);
+	if (cleanup_ret)
+		dev_warn(component->dev, "Failed to disable supplies: %d\n",
+			 cleanup_ret);
+	return ret;
 }
 
 static const struct snd_soc_dai_ops sta32x_dai_ops = {

base-commit: 32b4e6b134c62e14291206da331891e99e2fb63d
-- 
2.50.1