ASoC: soc-pcm: add soc_pcm_hw_clean() and call it from soc_pcm_hw_params/free()

soc_pcm_hw_params() does rollback when failed (A),
but, it is almost same as soc_pcm_hw_free().

	static int soc_pcm_hw_params(xxx)
	{
		...
		if (ret < 0)
			goto xxx_err;
		...
		return ret;

 ^	component_err:
 |		...
 |	interface_err:
(A)		...
 |	codec_err:
 |		...
 v		return ret;
	}

The difference is
soc_pcm_hw_free() is for all dai/component/substream,
rollback          is for succeeded part only.

This kind of duplicated code can be a hotbed of bugs,
thus, we want to share soc_pcm_hw_free() and rollback.

Now, soc_pcm_hw_params/free() are handling
	1) snd_soc_link_hw_params/free()
	2) snd_soc_pcm_component_hw_params/free()
	3) snd_soc_dai_hw_params/free()

Now, 1) to 3) are handled.
This patch adds new soc_pcm_hw_clean() and call it from
soc_pcm_hw_params() as rollback, and from soc_pcm_hw_free() as
normal close handler.

Other difference is that soc_pcm_hw_free() handles digital mute
if it was last user. Rollback also handles it by this patch.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87h7rhgqab.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/soc.h

@@ -1184,14 +1184,10 @@ struct snd_soc_pcm_runtime {
 	for ((i) = 0;							\
 	     ((i) < rtd->num_cpus) && ((dai) = asoc_rtd_to_cpu(rtd, i)); \
 	     (i)++)
-#define for_each_rtd_cpu_dais_rollback(rtd, i, dai)		\
-	for (; (--(i) >= 0) && ((dai) = asoc_rtd_to_cpu(rtd, i));)
 #define for_each_rtd_codec_dais(rtd, i, dai)				\
 	for ((i) = 0;							\
 	     ((i) < rtd->num_codecs) && ((dai) = asoc_rtd_to_codec(rtd, i)); \
 	     (i)++)
-#define for_each_rtd_codec_dais_rollback(rtd, i, dai)		\
-	for (; (--(i) >= 0) && ((dai) = asoc_rtd_to_codec(rtd, i));)
 #define for_each_rtd_dais(rtd, i, dai)					\
 	for ((i) = 0;							\
 	     ((i) < (rtd)->num_cpus + (rtd)->num_codecs) &&		\

sound/soc/soc-pcm.c

@@ -860,10 +860,7 @@ static void soc_pcm_codec_params_fixup(struct snd_pcm_hw_params *params,
 	interval->max = channels;
 }
 
-/*
+static int soc_pcm_hw_clean(struct snd_pcm_substream *substream, int rollback)
- * Frees resources allocated by hw_params, can be called multiple times
- */
-static int soc_pcm_hw_free(struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 	struct snd_soc_dai *dai;
@@ -886,23 +883,31 @@ static int soc_pcm_hw_free(struct snd_pcm_substream *substream)
 	}
 
 	/* free any machine hw params */
-	snd_soc_link_hw_free(substream, 0);
+	snd_soc_link_hw_free(substream, rollback);
 
 	/* free any component resources */
-	snd_soc_pcm_component_hw_free(substream, 0);
+	snd_soc_pcm_component_hw_free(substream, rollback);
 
 	/* now free hw params for the DAIs  */
 	for_each_rtd_dais(rtd, i, dai) {
 		if (!snd_soc_dai_stream_valid(dai, substream->stream))
 			continue;
 
-		snd_soc_dai_hw_free(dai, substream, 0);
+		snd_soc_dai_hw_free(dai, substream, rollback);
 	}
 
 	mutex_unlock(&rtd->card->pcm_mutex);
 	return 0;
 }
 
+/*
+ * Frees resources allocated by hw_params, can be called multiple times
+ */
+static int soc_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	return soc_pcm_hw_clean(substream, 0);
+}
+
 /*
  * Called by ALSA when the hardware params are set by application. This
  * function can also be called multiple times and can allocate buffers
@@ -963,7 +968,7 @@ static int soc_pcm_hw_params(struct snd_pcm_substream *substream,
 		ret = snd_soc_dai_hw_params(codec_dai, substream,
 					    &codec_params);
 		if(ret < 0)
-			goto codec_err;
+			goto out;
 
 		codec_dai->rate = params_rate(&codec_params);
 		codec_dai->channels = params_channels(&codec_params);
@@ -983,7 +988,7 @@ static int soc_pcm_hw_params(struct snd_pcm_substream *substream,
 
 		ret = snd_soc_dai_hw_params(cpu_dai, substream, params);
 		if (ret < 0)
-			goto interface_err;
+			goto out;
 
 		/* store the parameters for each DAI */
 		cpu_dai->rate = params_rate(params);
@@ -995,41 +1000,12 @@ static int soc_pcm_hw_params(struct snd_pcm_substream *substream,
 	}
 
 	ret = snd_soc_pcm_component_hw_params(substream, params);
-	if (ret < 0)
-		goto component_err;
-
 out:
 	mutex_unlock(&rtd->card->pcm_mutex);
-	return ret;
 
-component_err:
+	if (ret < 0)
-	snd_soc_pcm_component_hw_free(substream, 1);
+		soc_pcm_hw_clean(substream, 1);
 
-	i = rtd->num_cpus;
-
-interface_err:
-	for_each_rtd_cpu_dais_rollback(rtd, i, cpu_dai) {
-		if (!snd_soc_dai_stream_valid(cpu_dai, substream->stream))
-			continue;
-
-		snd_soc_dai_hw_free(cpu_dai, substream, 1);
-		cpu_dai->rate = 0;
-	}
-
-	i = rtd->num_codecs;
-
-codec_err:
-	for_each_rtd_codec_dais_rollback(rtd, i, codec_dai) {
-		if (!snd_soc_dai_stream_valid(codec_dai, substream->stream))
-			continue;
-
-		snd_soc_dai_hw_free(codec_dai, substream, 1);
-		codec_dai->rate = 0;
-	}
-
-	snd_soc_link_hw_free(substream, 1);
-
-	mutex_unlock(&rtd->card->pcm_mutex);
 	return ret;
 }