ALSA: hda - Fix initialization of secondary capture source on VT1705

VT1705 codec has two ADCs where the secondary ADC has no MUX but only
a fixed connection to the mic pin.  This confused the driver and it
tries always overriding the input-source selection by assumption of
the existing MUX for the secondary ADC, resulted in resetting the
input-source at each time PM (including power-saving) occurs.

The fix is simply to check the existence of MUX for secondary ADCs in
the initialization code.

Tested-by: Anisse Astier <anisse@astier.eu>
Cc: <stable@kernel.org> [v3.1+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/sound/pci/hda/patch_via.c b/sound/pci/hda/patch_via.c
index 284e311040fe..dff9a00ee8fb 100644
--- a/sound/pci/hda/patch_via.c
+++ b/sound/pci/hda/patch_via.c
@@ -666,6 +666,9 @@ static void via_auto_init_analog_input(struct hda_codec *codec)
         /* init input-src */
         for (i = 0; i < spec->num_adc_nids; i++) {
                 int adc_idx = spec->inputs[spec->cur_mux[i]].adc_idx;
+                /* secondary ADCs must have the unique MUX */
+                if (i > 0 && !spec->mux_nids[i])
+                        break;
                 if (spec->mux_nids[adc_idx]) {
                         int mux_idx = spec->inputs[spec->cur_mux[i]].mux_idx;
                         snd_hda_codec_write(codec, spec->mux_nids[adc_idx], 0,