[DNM] ASoC: soc-pcm/soc-compress: Unwind FE/BE triggers on failure

include/sound/soc-dpcm.h

@@ -77,6 +77,12 @@ struct snd_soc_dpcm {
 	struct list_head list_be;
 	struct list_head list_fe;
 
+	/*
+	 * BE reference taken for the FE by START, RESUME or PAUSE_RELEASE,
+	 * only accessed from the trigger path of the FE
+	 */
+	bool trigger_ref;
+
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debugfs_state;
 #endif

sound/soc/soc-component.c

@@ -12,6 +12,7 @@
 #include <linux/pm_runtime.h>
 #include <sound/soc.h>
 #include <linux/bitops.h>
+#include "soc-internal.h"
 
 #define soc_component_ret(dai, ret) _soc_component_ret(dai, __func__, ret)
 static inline int _soc_component_ret(struct snd_soc_component *component, const char *func, int ret)
@@ -456,6 +457,7 @@ int snd_soc_component_compr_trigger(struct snd_compr_stream *cstream, int cmd)
 {
 	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
 	struct snd_soc_component *component;
+	int unwind_cmd;
 	int i, ret;
 
 	for_each_rtd_components(rtd, i, component) {
@@ -464,11 +466,30 @@ int snd_soc_component_compr_trigger(struct snd_compr_stream *cstream, int cmd)
 			ret = component->driver->compress_ops->trigger(
 				component, cstream, cmd);
 			if (ret < 0)
-				return soc_component_ret(component, ret);
+				goto unwind;
 		}
 	}
 
 	return 0;
+
+unwind:
+	ret = soc_component_ret(component, ret);
+
+	unwind_cmd = snd_soc_trigger_unwind_cmd(cmd);
+	if (unwind_cmd < 0)
+		return ret;
+
+	/* Unwind the components that have been triggered before the failing one */
+	while (--i >= 0) {
+		component = rtd->components[i];
+		if (component->driver->compress_ops &&
+		    component->driver->compress_ops->trigger)
+			component->driver->compress_ops->trigger(component,
+								 cstream,
+								 unwind_cmd);
+	}
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(snd_soc_component_compr_trigger);
 

sound/soc/soc-compress.c

@@ -282,6 +282,7 @@ static int soc_compr_open_fe(struct snd_compr_stream *cstream)
 	dpcm_path_put(&list);
 
 	fe->dpcm[stream].state = SND_SOC_DPCM_STATE_OPEN;
+	fe->dpcm[stream].fe_pause = false;
 	fe->dpcm[stream].runtime_update = SND_SOC_DPCM_UPDATE_NO;
 
 	snd_soc_runtime_activate(fe, stream);
@@ -365,6 +366,7 @@ static int soc_compr_trigger(struct snd_compr_stream *cstream, int cmd)
 	struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
 	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
 	int stream = cstream->direction; /* SND_COMPRESS_xxx is same as SNDRV_PCM_STREAM_xxx */
+	int unwind_cmd;
 	int ret;
 
 	snd_soc_dpcm_mutex_lock(rtd);
@@ -374,8 +376,12 @@ static int soc_compr_trigger(struct snd_compr_stream *cstream, int cmd)
 		goto out;
 
 	ret = snd_soc_dai_compr_trigger(cpu_dai, cstream, cmd);
-	if (ret < 0)
+	if (ret < 0) {
+		unwind_cmd = snd_soc_trigger_unwind_cmd(cmd);
+		if (unwind_cmd >= 0)
+			snd_soc_component_compr_trigger(cstream, unwind_cmd);
 		goto out;
+	}
 
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
@@ -391,26 +397,45 @@ static int soc_compr_trigger(struct snd_compr_stream *cstream, int cmd)
 	return ret;
 }
 
+static int soc_compr_trigger_fe_only(struct snd_compr_stream *cstream, int cmd)
+{
+	struct snd_soc_pcm_runtime *fe = cstream->private_data;
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(fe, 0);
+	int unwind_cmd;
+	int ret;
+
+	ret = snd_soc_dai_compr_trigger(cpu_dai, cstream, cmd);
+	if (ret < 0)
+		return ret;
+
+	ret = snd_soc_component_compr_trigger(cstream, cmd);
+	if (ret < 0) {
+		unwind_cmd = snd_soc_trigger_unwind_cmd(cmd);
+		if (unwind_cmd >= 0)
+			snd_soc_dai_compr_trigger(cpu_dai, cstream, unwind_cmd);
+	}
+
+	return ret;
+}
+
 static int soc_compr_trigger_fe_be(struct snd_compr_stream *cstream, int cmd,
 				   bool fe_first)
 {
 	struct snd_soc_pcm_runtime *fe = cstream->private_data;
-	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(fe, 0);
+	int unwind_cmd = snd_soc_trigger_unwind_cmd(cmd);
 	int ret;
 
 	if (fe_first) {
 		dev_dbg(fe->dev, "ASoC: pre trigger FE %s cmd %d\n",
 			fe->dai_link->name, cmd);
 
-		ret = snd_soc_dai_compr_trigger(cpu_dai, cstream, cmd);
-		if (ret < 0)
-			goto out;
-
-		ret = snd_soc_component_compr_trigger(cstream, cmd);
+		ret = soc_compr_trigger_fe_only(cstream, cmd);
 		if (ret < 0)
 			goto out;
 
 		ret = dpcm_be_dai_trigger(fe, cstream->direction, cmd);
+		if (ret < 0 && unwind_cmd >= 0)
+			soc_compr_trigger_fe_only(cstream, unwind_cmd);
 	} else {
 		dev_dbg(fe->dev, "ASoC: post trigger FE %s cmd %d\n",
 			fe->dai_link->name, cmd);
@@ -419,11 +444,9 @@ static int soc_compr_trigger_fe_be(struct snd_compr_stream *cstream, int cmd,
 		if (ret < 0)
 			goto out;
 
-		ret = snd_soc_dai_compr_trigger(cpu_dai, cstream, cmd);
+		ret = soc_compr_trigger_fe_only(cstream, cmd);
 		if (ret < 0)
-			goto out;
-
-		ret = snd_soc_component_compr_trigger(cstream, cmd);
+			dpcm_be_dai_trigger_unwind(fe, cstream->direction, cmd);
 	}
 
 out:

sound/soc/soc-internal.h

@@ -36,4 +36,28 @@ struct clk *snd_soc_dai_get_bclk(struct snd_soc_dai *dai);
 unsigned int snd_soc_dai_get_bclk_ratio(struct snd_soc_dai *dai);
 void snd_soc_dai_active_update(struct snd_soc_dai *dai, int stream, int action);
 
+/*
+ * In soc-pcm
+ */
+void dpcm_be_dai_trigger_unwind(struct snd_soc_pcm_runtime *fe, int stream,
+				int cmd);
+
+/*
+ * Get the trigger command to unwind a failed START, RESUME or PAUSE_RELEASE.
+ * Returns -EINVAL for commands that are not unwound.
+ */
+static inline int snd_soc_trigger_unwind_cmd(int cmd)
+{
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		return SNDRV_PCM_TRIGGER_STOP;
+	case SNDRV_PCM_TRIGGER_RESUME:
+		return SNDRV_PCM_TRIGGER_SUSPEND;
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		return SNDRV_PCM_TRIGGER_PAUSE_PUSH;
+	default:
+		return -EINVAL;
+	}
+}
+
 #endif /* __SOC_INTERNAL_H */