ALSA: hda/realtek - Don't create alt-stream for capture when unnecessary

When the driver finds multiple ADCs, it tries to create an alternative
capture PCM stream.  However, these secondary ADCs might be useless or
in uncontrolled paths in some cases, e.g. when auto-mic or dynamic
ADC-switching is enabled.  Also, when only a single capture source is
available, the multi-streams don't make sense, too.

With this patch, the driver checks such condition and skips the alt
stream appropriately.

Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_realtek.c

@@ -2270,6 +2270,7 @@ static int alc_build_pcms(struct hda_codec *codec)
 	struct alc_spec *spec = codec->spec;
 	struct hda_pcm *info = spec->pcm_rec;
 	const struct hda_pcm_stream *p;
+	bool have_multi_adcs;
 	int i;
 
 	codec->num_pcms = 1;
@@ -2348,8 +2349,11 @@ static int alc_build_pcms(struct hda_codec *codec)
 	/* If the use of more than one ADC is requested for the current
 	 * model, configure a second analog capture-only PCM.
 	 */
+	have_multi_adcs = (spec->num_adc_nids > 1) &&
+		!spec->dyn_adc_switch && !spec->auto_mic &&
+		(!spec->input_mux || spec->input_mux->num_items > 1);
 	/* Additional Analaog capture for index #2 */
-	if (spec->alt_dac_nid || spec->num_adc_nids > 1) {
+	if (spec->alt_dac_nid || have_multi_adcs) {
 		codec->num_pcms = 3;
 		info = spec->pcm_rec + 2;
 		info->name = spec->stream_name_analog;
@@ -2365,7 +2369,7 @@ static int alc_build_pcms(struct hda_codec *codec)
 				alc_pcm_null_stream;
 			info->stream[SNDRV_PCM_STREAM_PLAYBACK].nid = 0;
 		}
-		if (spec->num_adc_nids > 1) {
+		if (have_multi_adcs) {
 			p = spec->stream_analog_alt_capture;
 			if (!p)
 				p = &alc_pcm_analog_alt_capture;