ALSA: hda: conexant: Remove mic bias threshold override

[ Upstream commit f52524d ]

Remove the mic bias current comparator threshold override (NID 0x1c,
verb 0x320, value 0x010) from Conexant codec driver.

This override was originally intended to support volume up/down controls on
headsets with inline remote controls, but it causes microphone detection
failures on some headsets with impedance less than 1k ohm.

After consulting with the vendor's engineers, it was confirmed that this
setting is board-specific and should be handled by BIOS/firmware rather
than the generic codec driver, especially since inline remote support
is not currently implemented.

Fixes: 7aeb259 ("ALSA: hda/conexant: Fix headset auto detect fail in cx8070 and SN6140")
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Heng <zhangheng@kylinos.cn>
Link: https://patch.msgid.link/20260713100329.306892-1-zhangheng@kylinos.cn
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Zhang Heng

sound/pci/hda/patch_conexant.c

@@ -168,9 +168,6 @@ static void cx_fixup_headset_recog(struct hda_codec *codec)
 {
 	unsigned int mic_present;
 
-	/* fix some headset type recognize fail issue, such as EDIFIER headset */
-	/* set micbias output current comparator threshold from 66% to 55%. */
-	snd_hda_codec_write(codec, 0x1c, 0, 0x320, 0x010);
 	/* set OFF voltage for DFET from -1.2V to -0.8V, set headset micbias register
 	 * value adjustment trim from 2.2K ohms to 2.0K ohms.
 	 */