A little note about ALSA and x220i thinkpad

First of all you need to find out sound cards indexes.
#> cat /proc/asound/cards
0 [PCH]:         HDA-Intel - HDA Intel PCH
                 HDA Intel PCH at 0xf2520000 irq 42
29 [ThinkPadEC]: ThinkPad EC - ThinkPad Console Audio Control
                 ThinkPad Console Audio Control at EC reg 0x30, fw unknown so HDA Intel PCH has index 0

#> /etc/asound.conf
pcm.!default {
   type hw
   card 0
}
ctl.!default {
   type hw
   card 0
}

cat /etc/modprobe.d/alsa-base
options snd-hda-intel model=laptop index=0
options snd-hda-intel model=thinkpad