I accidentally cracked the screen of my iPad 3, gave it out to an engineer to fix for me only to discover that I can no longer access it after the broken iPad screen have been repaired.
I could switch it off and power it on but couldn’t use the iPad beyond that. It only displays : “iPad disabled : Connect to iTunes”. I googled it and learnt that such happens after you might have entered the wrong password six times in a row.
Not surprised though because the iPad was misbehaving when the screen was bad. If you tap “A” on the iPad keypad, “B” might be entered in the password field. So, I assume the engineer accidentally entered the wrong password several times while trying to change the iPad screen.
Unfortunately, once you are locked out, you will never get another chance to enter your passcode even if you now remember it. You will need a PC to fix the problem and if you’ve not backed up your device, you will lose everything on it once you fix the problem with iTunes.
To cut the story short, I was able to restore my iPad by following the recovery method explained here. iPad was restored as new. Hence lost all data on it except the bookmarks and notes backed up to my iCloud account.
NOTE: You can also unlock your iPad via iCloud website as explained here. It will also erase i.e wipe your device.