Counter-Strike: All versions are already linux supported.
Half-Life 2: Most are ported, the game engine is ported to linux.
Team Fortress 2: Ported to linux.
Left 4 Dead 2: Used as the original test bed of steam for linux [1], I'm unware of if it has been ported.
Portal 2: Game Engine Ported, unaware of game's state.
Natural Selection 2: Developer has plans too, but game engine needs Direct3D layer. Claims it can be over come. [2]
Bioshock Infinite: Has no plans to be ported to linux, but has been ported to mac [3].
Civ V: Apparently supports PC/Mac/Linux/Unix according to its amazon page.
Serious Same BFE: Ported.
Call of Duty: Modern Warfare 3: Can run in linux via wine [4] if you trust that source, seems sketchy. But the publisher isn't linux friendly. [5] or maybe it is [6]. We don't know for sure, this is a developping story.
Metro LL: Is ported.
DiRT3: Uses Games for Windows Live. There's a few non-legal hacks to get it working but nothing offical.
BoardLands 2: Unreal Supports Linux [7], but there are no developer statements
A:tDD: Ported
Skyrim: Is actually Unsupported by their Developers (they've moved on to other projects). So porting it now seems unlikely. [8]
At this point we can say Controller =/= Linux Support.
[1] http://blogs.valvesoftware.com/linux/faster-zombies/
[2] http://unknownworlds.com/ns2/spark-engine-questions-and-answ...
[3] http://forums.2k.com/showthread.php?221791-Please-port-Biosh...
[4] http://community.callofduty.com/thread/200382760#.UqstR7TyRH...
[5] http://www.phoronix.com/scan.php?page=news_item&px=MTU0MTA
[6] http://www.phoronix.com/scan.php?page=news_item&px=MTU0MjE
[7] http://www.unrealengine.com/licensing/faq/
[8] http://steamcommunity.com/app/72850/discussions/0/8469626270...