Although today the z/OS V2.2 publications are not available on Knowledge Center, they will be very soon. The individual books are available as PDFs here: http://www-03.ibm.com/systems/z/os/zos/library/bkserv/v2r2pdf/ .
However, if you are like me, you want to have all the z/OS V2.2 PDFs handy. As you might have heard me say, I'm a heavy PDF user nowadays :). Well, the newly zipped up file of all the z/OS V2.2 books is available! Go to the IBM Publications Center ( http://www-05.ibm.com/e-business/linkweb/publications/servlet/pbi.wss ). The key piece of information you'll need is the publication number for the "ZIP of 7/28 IBM z/OS V2R2 PDF Documentation". That publication number is SC27-8430; search on this number. Right now, it's at the -00 level for this zip.
Now, if you look in that zip file, you'll see a directory (zOS V2R2 PDFs July 2015) that has three indexes in it. I've been hitting my head on the wall trying to find out what they are there for, and what they can do to help me. The answer so far is "ignore them, they do nothing". If I find anything else out about them, I'll update this blog. Just wanted to point that out, so that you can avoid the headaches I've encountered trying to find out about them.
If you need all the z/OS V2.2 PDFs, this is best place to find them.