Comment 128 for bug 1516025

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

Early Patching
~~~~~~~~~~~~~~
When CONFIG_SND_HDA_PATCH_LOADER=y is set, you can pass a "patch" as a
firmware file for modifying the HD-audio setup before initializing the
codec. This can work basically like the reconfiguration via sysfs in
the above, but it does it before the first codec configuration.

A patch file is a plain text file which looks like below:

------------------------------------------------------------------------
  [codec]
  0x12345678 0xabcd1234 2

  [model]
  auto

  [pincfg]
  0x12 0x411111f0

did you set the correct codec id and subsystem id and model

since you need model dell-headset-multi to call the function alc_fixup_headset_mode_alc668 to init the headset

and those pin fix to remove headphone mic by the original mic jack and subwoofer
remove the headphone jack so that line out type =speaker for the 2.1 channel map