Comment 18 for bug 1332900

https://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/commit/sound/pci/hda/hda_auto_parser.c?id=1c70a583417e8db1e1d5069d7651ba294e9499de

using hda Jack retask to add headset mic

and specify hint by modifying hda-jack-retask.fw generated by hda Jack retask

parser_flags = 4

to force the parser to find headset Mic which have specific sequence number 0x0c and set misc bit (bit 8)

https://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/tree/Documentation/sound/alsa/HD-Audio.txt

however the current logic of auto Mic selection won't consider the extra Mic jack in alienware