ASoC: soc-pcm: merge DPCM and non-DPCM validation check

DPCM and non-DPCM validation check are very similar. The big difference
is that DPCM doesn't check Codec validation. This is historical reason.
It should be checked, but it breaks existing driver/behavior.

Anyway, if we uses dummy DAI as Codec when DPCM case, there is no
difference between DPCM and non-DPCM. Let's merge these.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://patch.msgid.link/8734kq9vgq.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: morimoto

sound/soc/soc-pcm.c

@@ -2822,7 +2822,11 @@ static int soc_get_playback_capture(struct snd_soc_pcm_runtime *rtd,
 {
 	struct snd_soc_dai_link *dai_link = rtd->dai_link;
 	struct snd_soc_dai *cpu_dai;
+	struct snd_soc_dai *codec_dai;
 	struct snd_soc_dai_link_ch_map *ch_maps;
+	struct snd_soc_dai *dummy_dai = snd_soc_find_dai(&snd_soc_dummy_dlc);
+	int cpu_capture;
+	int cpu_playback;
 	int has_playback = 0;
 	int has_capture  = 0;
 	int i;
@@ -2832,40 +2836,38 @@ static int soc_get_playback_capture(struct snd_soc_pcm_runtime *rtd,
 		return -EINVAL;
 	}
 
-	if (dai_link->dynamic || dai_link->no_pcm) {
-
-		for_each_rtd_ch_maps(rtd, i, ch_maps) {
-			cpu_dai	  = snd_soc_rtd_to_cpu(rtd,   ch_maps->cpu);
-
-			if (snd_soc_dai_stream_valid(cpu_dai, SNDRV_PCM_STREAM_PLAYBACK))
-				has_playback = 1;
-
-			if (snd_soc_dai_stream_valid(cpu_dai, SNDRV_PCM_STREAM_CAPTURE))
-				has_capture = 1;
-		}
-
-	} else {
-		struct snd_soc_dai *codec_dai;
+	/* Adapt stream for codec2codec links */
+	cpu_capture  = snd_soc_get_stream_cpu(dai_link, SNDRV_PCM_STREAM_CAPTURE);
+	cpu_playback = snd_soc_get_stream_cpu(dai_link, SNDRV_PCM_STREAM_PLAYBACK);
 
-		/* Adapt stream for codec2codec links */
-		int cpu_capture  = snd_soc_get_stream_cpu(dai_link, SNDRV_PCM_STREAM_CAPTURE);
-		int cpu_playback = snd_soc_get_stream_cpu(dai_link, SNDRV_PCM_STREAM_PLAYBACK);
+	/*
+	 * see
+	 *	soc.h :: [dai_link->ch_maps Image sample]
+	 */
+	for_each_rtd_ch_maps(rtd, i, ch_maps) {
+		cpu_dai	  = snd_soc_rtd_to_cpu(rtd,   ch_maps->cpu);
+		codec_dai = snd_soc_rtd_to_codec(rtd, ch_maps->codec);
 
 		/*
-		 * see
-		 *	soc.h :: [dai_link->ch_maps Image sample]
+		 * FIXME
+		 *
+		 * DPCM Codec has been no checked before.
+		 * It should be checked, but it breaks compatibility.
+		 *
+		 * For example there is a case that CPU have loopback capabilities which is used
+		 * for tests on boards where the Codec has no capture capabilities. In this case,
+		 * Codec capture validation check will be fail, but system should allow capture
+		 * capabilities. We have no solution for it today.
 		 */
-		for_each_rtd_ch_maps(rtd, i, ch_maps) {
-			cpu_dai	  = snd_soc_rtd_to_cpu(rtd,   ch_maps->cpu);
-			codec_dai = snd_soc_rtd_to_codec(rtd, ch_maps->codec);
-
-			if (snd_soc_dai_stream_valid(codec_dai, SNDRV_PCM_STREAM_PLAYBACK) &&
-			    snd_soc_dai_stream_valid(cpu_dai,   cpu_playback))
-				has_playback = 1;
-			if (snd_soc_dai_stream_valid(codec_dai, SNDRV_PCM_STREAM_CAPTURE) &&
-			    snd_soc_dai_stream_valid(cpu_dai,   cpu_capture))
-				has_capture = 1;
-		}
+		if (dai_link->dynamic || dai_link->no_pcm)
+			codec_dai = dummy_dai;
+
+		if (snd_soc_dai_stream_valid(codec_dai, SNDRV_PCM_STREAM_PLAYBACK) &&
+		    snd_soc_dai_stream_valid(cpu_dai,   cpu_playback))
+			has_playback = 1;
+		if (snd_soc_dai_stream_valid(codec_dai, SNDRV_PCM_STREAM_CAPTURE) &&
+		    snd_soc_dai_stream_valid(cpu_dai,   cpu_capture))
+			has_capture = 1;
 	}
 
 	if (dai_link->playback_only)