ALSA: hda - Add snd_hda_get_default_vref() helper function

Add a new helper function to guess the default VREF pin control bits
for mic in.  This can be used to set the pin control value safely
matching with the actual pin capabilities.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_cirrus.c

@@ -1057,12 +1057,8 @@ static void init_input(struct hda_codec *codec)
 			continue;
 		/* set appropriate pin control and mute first */
 		ctl = PIN_IN;
-		if (cfg->inputs[i].type == AUTO_PIN_MIC) {
-			unsigned int caps = snd_hda_query_pin_caps(codec, pin);
-			caps >>= AC_PINCAP_VREF_SHIFT;
-			if (caps & AC_PINCAP_VREF_80)
-				ctl = PIN_VREF80;
-		}
+		if (cfg->inputs[i].type == AUTO_PIN_MIC)
+			ctl |= snd_hda_get_default_vref(codec, pin);
 		snd_hda_set_pin_ctl(codec, pin, ctl);
 		snd_hda_codec_write(codec, spec->adc_nid[i], 0,
 				    AC_VERB_SET_AMP_GAIN_MUTE,