ALSA: hda - proc - show which I/O NID is associated to PCM device

Output something like:

Node 0x02 [Audio Output] wcaps 0x11: Stereo
  Device: name="ALC888 Analog", type="Audio", device=0, substream=0
  Converter: stream=0, channel=0
  ...
Signed-off-by: NJaroslav Kysela <perex@perex.cz>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_codec.c

@@ -2877,14 +2877,15 @@ static int set_pcm_default_values(struct hda_codec *codec,
 	return 0;
 }
 
+const char *snd_hda_pcm_type_name[HDA_PCM_NTYPES] = {
+	"Audio", "SPDIF", "HDMI", "Modem"
+};
+
 /*
  * get the empty PCM device number to assign
  */
 static int get_empty_pcm_device(struct hda_bus *bus, int type)
 {
-	static const char *dev_name[HDA_PCM_NTYPES] = {
-		"Audio", "SPDIF", "HDMI", "Modem"
-	};
 	/* audio device indices; not linear to keep compatibility */
 	static int audio_idx[HDA_PCM_NTYPES][5] = {
 		[HDA_PCM_TYPE_AUDIO] = { 0, 2, 4, 5, -1 },
@@ -2903,7 +2904,7 @@ static int get_empty_pcm_device(struct hda_bus *bus, int type)
 		if (!test_and_set_bit(audio_idx[type][i], bus->pcm_dev_bits))
 			return audio_idx[type][i];
 
-	snd_printk(KERN_WARNING "Too many %s devices\n", dev_name[type]);
+	snd_printk(KERN_WARNING "Too many %s devices\n", snd_hda_pcm_type_name[type]);
 	return -EAGAIN;
 }
 

sound/pci/hda/hda_codec.h

@@ -894,6 +894,7 @@ int snd_hda_codec_build_controls(struct hda_codec *codec);
 /*
  * PCM
  */
+extern const char *snd_hda_pcm_type_name[];
 int snd_hda_build_pcms(struct hda_bus *bus);
 int snd_hda_codec_build_pcms(struct hda_codec *codec);
 void snd_hda_codec_setup_stream(struct hda_codec *codec, hda_nid_t nid,

sound/pci/hda/hda_proc.c

@@ -309,7 +309,21 @@ static void print_audio_io(struct snd_info_buffer *buffer,
 			   struct hda_codec *codec, hda_nid_t nid,
 			   unsigned int wid_type)
 {
-	int conv = snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_CONV, 0);
+	int pcm, conv;
+	for (pcm = 0; pcm < codec->num_pcms; pcm++) {
+		int type;
+		struct hda_pcm *cpcm = &codec->pcm_info[pcm];
+		for (type = 0; type < 2; type++) {
+			if (cpcm->stream[type].nid != nid || cpcm->pcm == NULL)
+				continue;
+			snd_iprintf(buffer, "  Device: name=\"%s\", type=\"%s\", device=%i, substream=%i\n",
+				cpcm->name,
+				snd_hda_pcm_type_name[cpcm->pcm_type],
+				cpcm->pcm->device,
+				cpcm->pcm->streams[type].substream->number);
+		}
+	}
+	conv = snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_CONV, 0);
 	snd_iprintf(buffer,
 		    "  Converter: stream=%d, channel=%d\n",
 		    (conv & AC_CONV_STREAM) >> AC_CONV_STREAM_SHIFT,