Unfortunately it can be difficult to determine before hand what the company's reaction will be, and especially in larger companies it can depend which department you are in.
One useful technique is to look for or ask for copies of their policy on disabilities and medical conditions. If they don't have a policy that's probably a bad sign.
Beyond that it's best to wait until they have shown interest in you. Depending on the severity of your condition you might be able to do interviews and progress quite far before it becomes an issue. Once they are seriously considering you as a potential employee it is easier to simply tell them about your condition, explain what support or adaptations you will need, and ask if they feel that is okay.
It does potentially waste some of your time, but telling them up front before they actually know you and understand that it's not something scary or debilitating might get you nowhere. And of course, you have to be willing to walk away if it doesn't seem right.