You can check the fuse rating for a rough idea. Just an idea, I have not checked it. I have been able to charge my laptop, but the fuse was blown when i purchased the car at 78k.

 

Have you tried looking in the owners manual? If you don’t have it, you can download a PDF copy on Toyota’s website here. See page 180, where it says not to exceed 120 watts. That’s 1 amp at 120 Volts. Enough for most chargers.