[alsa-devel] [PATCH] ALSA: hda - Disable Headphone Mic boost for ALC662

[David Henningsson]

When headphone mic boost is above zero, some 10 - 20 second delay
might occur before the headphone mic is operational.
Therefore disable the headphone mic boost control (recording gain is
sufficient even without it).

(Note: this patch is not about the headset mic, it's about the less
common mic-in only mode.)

BugLink: https://bugs.launchpad.net/bugs/1454235
Suggested-by: Kailang Yang <kailang at realtek.com>
Signed-off-by: David Henningsson <david.henningsson at canonical.com>
---
 sound/pci/hda/patch_realtek.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index d0fa455..87605fc 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -4240,6 +4240,10 @@ static void alc_fixup_headset_mode_alc662(struct hda_codec *codec,
 	if (action == HDA_FIXUP_ACT_PRE_PROBE) {
 		spec->parse_flags |= HDA_PINCFG_HEADSET_MIC;
 		spec->gen.hp_mic = 1; /* Mic-in is same pin as headphone */
+
+		/* Disable boost for mic-in permanently */
+		snd_hda_codec_write(codec, 0x1b, 0, AC_VERB_SET_AMP_GAIN_MUTE, 0x7000);
+		snd_hda_override_wcaps(codec, 0x1b, get_wcaps(codec, 0x1b) & ~AC_WCAP_IN_AMP);
 	} else
 		alc_fixup_headset_mode(codec, fix, action);
 }
-- 
1.9.1